WADERS AND OTHER W ATERBIRDS IN THE
UNITED ARAB EMIRATES
autumn 1994 & spring 1995
Guido O. Keijl, Paul S. Ruitcrs, Tom M. van dcr Have, Abraham bij de Vaate, Eric C.L. Marteijn & Ruurd Noordhuis
FOUNDATION WORKING GROUP INTERNATIONAL W ATERBIRD AND WETLAND RESEARCH
WIWO-report 62,1998 The WIWO report series intends to be a regular medium by which occasional reports of ornithological expeditions or journeys can be published. In this way, regular distribution and availability are guaranteed. Large quality differences are accepted, since the authors remain responsible.
This report can be ordered by paying f 25,-, plus f J5,- administration-costs/or each separate order, to postal giro account 2.666 .009 or to ABN bank account 57.02.16.613 or Stichting WIWO, Fetha 23,3633 eT Vrecland, The Netherlands. It is important to mention the numbers of the reports required . Postage for surface mail is included in the prices. The administration costs are required to cover the bank costs for payments from abroad . They an! not due for payments from Dutch accounts or payments by Eurocheque, provided that the bank pa.l'snumher is filled in on the reverse side, or for cash payments. WADERS AND OTHER WATERBIRDS IN THE
UNITED ARAB ElVIIRA TES
autumn 1994 & spring 1995
Guido O. Keijl, Paul S. Ruiters, Tom M. van der Have, Abraham bij de Vaate, Eric c.L. Marteijn & Ruurd Noordhuis
FOUNDATION WORKING GROUP INTERNATIONAL WATERBIRD AND WETLAND RESEARCH
c/o P.O. Box 925 NL-3700 AX Zeist The Netherlahds
WIWO-report 62, 1998 Colophon
Project participants autumn 1994 - Guido O. Keijl & Paul S. Ruiters spring 1995 - Simon Aspinall, Bram bij de Vaate, Guido O. Keijl, Eric C.L. Marteijn, Ruurd Noordhuis, Paul S. Ruiters & Tom M. van der Have
In co-operation with National Avian Research Centre (NARC), Abu Dhabi Abu Dhabi Shorebird Project (ADSP), Abu Dhabi
Financial support National Avian Research Centre (NARC), Abu Dhabi Ministry of Agriculture, Nature Management and Fisheries, Internal Affairs (LNV) Fonds voor Onderzoek ten behoeve van het Natuurbehoud (FONA) Swedish Ornithological Society (SOF) ADCO ADMA-OPCO ETISALAT H.H. Sheikh Nahyan bin Mubarak al Nahyan H.H. Sheikh Mohammed bin Zayed al Nahyan Al Fahim Group
Editors: Guido Keijl & Paul Ruiters
Maps and figures: Paul Ruiters & Guido Keijl
Drawings: Guido Keijl
Published by: Stichting WIWO, Zeist, The Netherlands, 1998
© Stichting WIWO, Zeist. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, whether electronic, mechanical, by photocopying, recording or otherwise, without the prior permission of the copyright owner.
Citation:
Citation of separate chapters is preferred to citation of the complete report. Citation example:
Noordhuis, R. & A. bij de Vaate 1995. Intertidal macro-invertebrate fauna in the United Arab Emirates. In: G.O. Keijl & P.S. Ruiters (eds.). Waders and other waterbirds in the United Arab Emirates, autumn 1994 & spring 1995. Pp. 17-28. Wl WO-report 62, Zeist, The Netherlands. Waders and other waterbirds in the United Arab Emirates
CONTENTS
SUMMARY 3 I. FOREWORD 5 2. INTRODUCTION 7 3. ACKNOWLEDGEMENTS 9 4. DESCRIPTION OF THE STUDY AREA 11 5. INTERTIDAL MACRO-INVERTEBRATE FAUNA 5.1 Introduction 17 5.2 Methods 17 5.3 Results 19 5.4 Discussion 24 6. W ATERBIRD STUDIES 6.1 Numbers 29 6.2 Visible migration of waders 45 6.3 Biometry 54 6.4 Feeding observations 61 6.5 Breeding of Kentish Plovers at Khor Dubai 75 7. SPRING MIGRATION OF BROAD-BILLED SANDPIPERS IN KHOR DUBAI 77 8. CONCLUSIONS AND RECOMMENDATIONS 81 9. SUGGESTIONS FOR FUTURE RESEARCH 84 10. AVIFAUNA 85 REFERENCES 103
Appendices
Numbers of waterbirds, September - October 1994 108 2 Numbers of waterbirds, January 1995 111 3 Numbers of waterbirds, April - May 1995 115 4 Numbers of waterbirds Khor Dubai, April- May 1995 119 5 Numbers of waterbirds Ras Ghanada, April- May 1995 121 6 Departures of waders from Khor Dubai, April- May 1995 122 7 Departures of waders from Saudi Arabia, April - May 1991 123 8 Biometry of waders 125 9 Itinerary autumn 1994 & spring 1995 128 List of WIWO-reports 131 Waders and other waterbirds in the United Arab Emirates
2 Waders and other waterbirds in the United Arab Emirates
SUMMARY
In autumn 1994 and spring 1995 several coastal wetlands in the United Arab Emirates were surveyed for waders and other waterbirds (Figure 4.1). In Khor Dubai, a shallow lagoon just east of the city of Dubai, holding high numbers of waders and other waterbirds, a more detailed wader study was carried out (Figure 4.2). The study focused on Broad-billed Sandpipers, as part of this species' migration route and wintering grounds are still unclear. The main aims of this project were:
• to discover important areas for migrating Broad-billed Sandpipers;
• to study the migration ecology of Broad-billed Sandpipers;
• to estimate numbers of water birds in wetlands in the United Arab Emirates;
• to study the invertebrate fauna of Khor Dubai and other wetlands in the United Arab Emirates;
• to study the departure of migrating waders from Khor Dubai to the breeding grounds.
Waders and other waterbirds were counted in 13 marine and one fresh water wetlands. Khor Dubai held most waterbirds, both in spring and in autumn (Appendix 1-6). Waders always formed the dominant taxonomic group (Figure 6.1-6.3), except along the east coast, where gulls and terns were found in highest numbers. Khor Dubai was counted once every 3-7 days (Appendix 3) in order to be able to construct migration patterns (Figure 6.4). Peak migration of most species occurred during the last week of April and the first week of May. Khor Dubai holds some hundreds of Flamingos, which migrate north to their Iranian and Russian breeding colonies. Numbers are however kept artificially high by feeding. Broad-billed Sandpipers migrate through the UAE, mainly through Khor Dubai, in autumn and spring. In autumn 1986 about 4000 were counted in Khor Dubai, but before and after this year numbers exceeding 1000 individuals have never been seen again in this area any more. The total number using the area is unknown, as information on turn-over rate is lacking. Broad billed Sandpipers migrating through Khor Dubai probably spend the winter in Barr al Hikman, Oman, with c. 5000 individuals. It is not known where the majority of the Fenno-Scandian population winters, but the Arabian Gulf, including the Iranian coast, and Barr al Hikman and possibly West-Pakistan probably hosts the entire population. Khor Dubai is an important breeding area for Kentish Plovers (150-200 pairs). The breeding birds and their offspring are being threatened by alterations of the area, disturbance by people and dogs, and by future building activities. Conservation measures for Khor Dubai and its breeding birds are proposed (Chapter 6.5, Chapter 8). Densities of waders in Khor Dubai (number of birds per hectare) were much higher than elsewhere in the UAE (Table 6.16). From the density counts the estimated number of waders present at one particular moment in coastal wetlands during migration was calculated for spring and autumn (Table 6.16). A comparison is made between numbers and densities in the UAE and elsewhere. From Table 6.17 it becomes clear that the UAE holds internationally important numbers of most wader species.
3 Summary
For Grey Heron and Western Reef Egret, the heron species occurring in highest numbers, densities and total numbers staging in the UAE were also established (Table 6.18). No infonnation from other coun.tries is available for comparison. Khor Duhai holds especially high numbers of Grey Herons. Up to 7% ofthe West-Asian population of Westem Reef Egrets may use the UAE wetlands during autumn and spring. Other waterbird species occur in the UAE in important numbers as well: Socotra Cormorants {15-33% of the world population), Sooty Gulls (up to 7%) and various species of terns.
Data on migrating waders were collected during late afternoon at Khor Dubai. A total of 39 flocks (13 species, 1194 individuals) was seen leaving. Curlew Sandpiper and Little Stint left in largest numbers (Figure 6.5-6.8, Appendix 8). The largest emigration coincided with the largest drop in numbers present in the area (Figure 6.4). Numbers of waders leaving from Saudi Arabia (spring 1991, Appendix 9) were used for comparison, and to enlarge the data set. Most waders left in a northerly or northwesterly direction. A positive correlation was found between breeding latitude and departure date (Figure 6.9).
During eight nights in spring 1995 74 waders were caught (Appendix 10), mainly Curlew Sandpipers, Lesser Sandplovers and Kentish Plovers. Between early and late April these birds increased in weight (Curlew Sandpiper 30%, Lesser Sandplover 19%): for the first two species a positive correlation was found between weight and departure date. In Kentish Plovers such an increase was not found, and all birds probably belonged to the local breeding population. Foraging intensity was found to be high for all species (Table 6.11, Figure 6.l2). Food intake of Broad-billed Sandpipers, Curlew Sandpipers, Pacific Golden Plover, Lesser Sandplover and Grey Plover was studied in detail. All these birds were feeding mainly on ragworms. Broad billed Sandpipers were almost exclusively feeding in the softest mud and caught relatively small ragworms (Figure 6.12). Energy intake was calculated to be lower than energy expenditure (Table 6.14). Curlew Sandpipers and the three plover species on the other hand selected very large ragworms (Table 6.15, Figure 6.14). A marked difference was found between calculations from ragworm jaw lengths from faeces and from estimated worm lengths in the field (Figure 6.13). However the results may be, intake rate of Lesser Sandplovers was extremely high (Table 6.13).
Food for waders was studied in detail in Khor Dubai, but samples on macrozoobenthic animals were taken in six other areas as well. Compared to the other sampling areas Khor Dubai is rich in mudsnails and worms. Mudsnails however are not eaten by waders, probably because of their hard shell. Especially high numbers of mudsnails wer.e found near the planted mangroves. In most coastal areas waders are feeding on worms, while birds feeding on bivalves were more common in autumn than in spring (Figure 6.15). Waders feeding on crabs make up only a small proportion.
4 Waders and other waterbirds in the United Arab Emirates
1. FOREWORD Simon Aspinall senior ornithologist at National Avian Research Centre Abu Dhabi
The United Arab Emirates, with over 450 km of Arabian Gulf coastline, was made for waders and wader enthusiasts. Situated between West Asia and Africa its importance astride a migration flyway could well have been sunnised from any atlas. Concerted ecological studies are, however, only a very recent phenomenon here and it is fortunate indeed that so many experts are prepared to travel, often at their own expense and in their own time, to solve unanswered questions about waterfowl migra1ion and ecology. In the UAE, although mid-winter waterfowl counts are now routine, little was known about other times of year, largely due to the inhospitability of the region to fieldwork. Brushing this aside, there has now been thorough surveys twice in autumn and once in spring of the numbers, distribution and feeding ecology of passage waders. Ringing efforts have added valuable additional information on moult and migration strategies, age structure and origins of different visiting wader populations. This most recent study, by a Dutch team, really a crack team of WIWO connoisseurs, supported logistically by the Abu Dhabi based National Avian Research Center, conducted the most professional studies. A preliminary investigation in the autumn of 1994 led the team to concentrate on Khor Dubai. Nonetheless, counts and observations were made everywhere else access could be gained along an increasingly privately owned and developing foreshore. Supported by sampling studies of substrates and invertebrate populations this data will be put to good use - applied conservation is the principle goal rather than satisfaction of purely academic curiosity. Collection of the data and its rapid analysis and publication here provides the vital quantification to progress shorebird conservation in the UAE. The professionalism, dedication and endurance of Bram, Ruurd, Guido, Eric, Paul and Tom is to be admired. The high quality of their work is certainly a model for future visiting groups to emulate and aspire to. They are welcome back to the UAE at any time.
5 Introduction
6 Waders and other waterbirds in the United Arab Emirates
2. INTRODUCTION Guido Keijl & Paul Ruiters
The Broad-billed Sandpiper Limicola falcinellus is a little known wader species of the West Palaearctic region. The nominate subspecies apparently breeds mainly in the Fenno-Scandian taiga zone; distribution and population size in the adjacent Russian taiga zone are largely unknown but probably low (cf Svensson & Tomkovich 1997). In autumn this Fenno-Scandian population migrates mainly in a southeastern direction across Europe. Large numbers are then found staging in the Sivash, Crimea, southern Ukraine (Van der Winden et al. 1993, Iosif Chernichko pers. comm.) and in Khor Dubai (up to 4,000 in 1986, Uttley et al. 1988). In late autumn and winter the species is present in the southern Arabian Gulf and northeast Oman in low numbers (Uttley et al. 1988, Zwarts et al. \ 991, Green et al. 1992, 1994). The winter distribution, however, remains largely unknown, although it is possible that the main wintering areas are in Oman and possibly in western Pakistan. Other potential wintering areas may lie along the Saudi Arabian Gulf coast and along the Iranian coast in the northeastern part of the Arabian Gulf. In May, large numbers are again observed in the Sivash area, estimated to number 6,000 - 8,000 individuals, which constitutes between 18 and 40% of the European breeding population (Van der Winden et al. 1993, Svensson & Tomkovich 1997). Smaller numbers have been counted at a few sites along the Arabian Gulf coast of Saudi Arabia during the last week of April and the first week of May (Evans & Keijl 1993a). Ringing recoveries have proved a link between the Arabian Gulf, the Sivash lagoons and the north European breeding population (WIWO 1994, Keijl & Ruiters in prep., Iosif Chernichko pers. comm., S. Nilsen & R. Rae pers. comm.). The small population size, limited distribution, specialized foraging habits, habitat preference and the peculiar migration strategy renders the species vulnerable in terms of conservation. Therefore, more information on the migration ecology was needed, especially on the migration areas and the wintering grounds. This prompted the study of shorebirds in wetlands of the United Arab Emirates, and in particular Khor Dubai, in autumn 1994 (Keijl & Ruiters 1997) and spring 1995. Although the Broad-billed Sandpiper was the main subject during this study, attention was paid to other waders and waterbirds as well, since few studies in the Arabian Gulf have focused on waders (see e.g. Zwarts et al. 1991, Evans & Keijl 1993a).
- >
7 Introduction
Aims of the project
The main aims of this project were:
• to discover important areas for migrating Broad-billed Sandpipers; • to study the migration ecology of Broad-billed Sandpipers belonging to the European breeding population; • to estimate numbers of waterbirds in wetlands in the United Arab Emirates; • to study the invertebrate fauna of Khor Dubai and other wetlands in the United Arab Emirates; • to study the departure of migrating waders from Khor Dubai to their respective breeding grounds.
In this report the data of two field studies, carried out from 24 September to 12 October 1994 and 6 April to 13 May 1995 are presented. During the autumn period attention was mainly paid to distribution and numbers, while in spring emphasis was put to numbers, feeding ecology and departure. Waders and other waterbirds in the United Arab Emirates
3. ACKNOWLEDGEMENTS
His Highness Sheikh Mohammed bin Rashid Al Maktoum is thanked for permission to carry out field studies in Khor Dubai Wildlife Sanctuary. His Highness Sheikh Mohammed Bin Zayed Al Nahyan and H.E. Sheikh Nahyan Bin Mubarak al Nahyan kindly supported the autumn project, financially and in natura, as part of the Abu Dhabi Shorebird Project. Mr. Erik Hirschfeld is thanked for his invitation to join the Abu Dhabi Shorebird Project in autumn 1994, which was vital in preparing for the spring project. The National A vian Research Center (NARC) was the host organisation in the United Arab Emirates. Many thanks to Dr. Dick Hornby and staff of the Abu Dhabi office for hospitality and facilities. NARC is especially thanked for providing housing in the Ras Ghanada field station and equipment. This project was funded by the Ministry of Agriculture, Nature Management and Fisheries, International Affairs, the 'Fonds voor Onderzoek ten behoeve van het Natuurbehoud' (FONA), and the Swedish Ornithogical Society (SOF). Support, financial or in natura came from the Al Fahim Group, ADCO (free petrol), ADMA-OPCO, ETISALAT (mobile phones and free telephone calls within the Emirates), and NARC (use of apartment in Abu Dhabi, use of research equipment). Mr. Jeroen Steeghs, Embassy of the Kingdom of The Netherlands in Abu Dhabi is thanked for translating our passports for the UAE-officials, for his interest and other help during the preparations of the project. Mr. Joseph Platt, Wildlife Consultant to His Highness Sheikh Mohammed bin Rashid Al Maktoum, is thanked for arranging permission to carry out field studies in Khor Dubai. Mrs. Platt is thanked for introducing us to the Dutch community in Dubai. Thanks are due to Mr. Frans Bergfeld (Vogelbescherming Nederland, The Netherlands) for lending us the Swarovski telescope Habicht AT 80. Mr. Fred van der Lelie and Mr. Gertjan Martens (Hogeschool Holland, Diemen) kindly provided equipment. Mr. Colin Richardson and Mr. Simon Aspinall are thanked for their enthusiasm, hospitality and sharing their knowledge of birds and Khor Dubai. Many thanks to Mrs. Marijcke Jongbloed of the Arabian Leopard Trust for her hospitality, interest and sharing her knowledge of nature in the Emirates. Mr. John Ward and Mr. Mohammad A. Rahman Hassan, Department of Environmental Protection, Dubai Municipality, provided essential information on Khor Dubai. Thanks are due to dr. Rene Dekker from the National Museum of Natural History in Leiden, and Mrs. Tineke Prins from the Zoological Museum in Amsterdam, where we measured leg lengths of plovers, and to Mr. Jeroen Goud from the National Museum of Natural History in Leiden for identifying the molluscs. Erik and Catharina Hirschfeld generously invited us in their home and supported us with all kinds of information on the UAE, their people and, naturally, its bird life. The help and interest of Mr. Wim Fokker and Mr. Kees Koffijberg (WIWO) were vital to start up this project. Mr. Frans Schepers drew the logo. Thanks to the police guards of Khor Dubai for their interest in our wader study in general and catching sessions at night.
9 Description of the study area
. ------~ N
1
Aas al Khaimah Qaiwain Ajman Sharjah
Arabian Gulf Dubai
8 • 6
Abu Dhabi Oman
Figure 4.1 Map of United Arab Emirates with the seven Emirates indicated. The numbers refer to the wetlands visited: I = lebel Dhanna, 2 = Shaksa'eet al Ya'en, 3 = Abu al Abyadh, 4 = Halat Iamilah, 5 = Ad Dabbi'yyah, 6 = Al Ghar, 7 = Abu Dhabi, 8 = Ras Ghanada, 9 = Emirates Golf Course, }O = Khor Dubai, 11 = Khor Ajman, 12 = Khor al Beidah, 13 = Al lazirah al Hamra, 14 = Dibba, 15 = Khor Kalba. Inset: UAE in Arabian peninsula.
10 Waders and other waterbirds in the United Arab Emirates
4. DESCRIPTION OF THE STUDY AREAS Guido Keijl
The United Arab Emirates (UAE), on the southwestern side of the Arabian Gulf (Figure 4.1), is a federation of seven emirates. The largest emirates are Abu Dhabi and Dubai, the smaller ones Sharjah, Ajman, Ras al Khaimah, Umrn al Qaiwain and Fujairah. The most important products of the country are oil and gas. Oil was first found , and taken into production, in Abu Dhabi in 1959. In Dubai, oil production began about ten years later. Later on, Sharjah and Ras al Khaimah also found oil, while Umrn al Qaiwain and Ajman started to produce gas. Nowadays Abu Dhabi takes a share of about 70% of the Emirates' oil production.
The northwestern shoreline of the Emirates is flat and sandy or muddy, interspersed with natural stands of Black Mangrove Avicennia marina - the only species of mangrove occurring here - and scattered rocks. There are many islands, the majority of which are private property. There is no clear border between the shore and the bordering huge barren sabkhas (saline mudflats) and in most places the sea can come in freely. The islands range from mere mangrove stands to fairly large sandy islands with terrestrial plants. Many islands close to the mainland are connected with causeways and inhabited. The shoreline bordering the Indian Ocean is rocky and sandy, with some sandy inlets. In the south, near the Omani border, an old mangrove stand still survives at Khor Kalba. Along the northwestern coast it is rather difficult to visit the shore in most places, except where there are roads. The entire coastline between Abu Dhabi and Dubai for example, with a length of approximately 120 km as the wader flies, is therefore virtually inaccessible.
The tide formed a problem during the visit in autumn: sometimes the tide came in at times other than predicted by the tide-table (Admiralty Method NP159, program by Chris Jackson, IAL), hence making counting difficult, if not impossible, because of (lack of) wader movements; in several cases the tide did not come in at all. Because of our time schedule we could not visit every site during both high and low tide. Therefore it is possible that Broad billed Sandpipers were overlooked, because they were foraging too far out, or roosting and thus hiding between other waders and/or between vegetation. Information for the description of the wetlands was compiled on the spot. Additional information was taken from Richardson (1990), Evans (1994), Richardson et al. (1994) and Aspinall (1995).
KhorDubai Khor Dubai (khor = tidal inlet or coastal lagoon) lies about 5 km east of Dubai city and 7 km inland. The entire lagoon used to be a shallow and connected to the Arabian Gulf by a 10 km long creek, intersecting Dubai city. The creek is much altered, but only less than half (the southwestern half) is still in the original state and shallow (on average <2 m), while the northwestern part has been dredged for industrial purposes and is now too deep to fall dry during low tides (Figure 4.2). This part is hardly of interest to birds any more. The two parts are separated by a boom. There are two islands, one in the shallow part, one (artificially constructcd) in the dredged part. On the eastern side a police post is erected, to guard the area. Another police post on the west side was not used during our stay.
11 Description of the study area
[;::: I:Idredged • sampling site main road
11 mudflats boom track mangroves additional sampling transect
Figure 4.2 Map of Khor Dubai Wildlife Sanctuary, with the 20 sampl ing locations indicated. The border of the sanctuary is formed by the edge of the mudflats and the floating line.
The shallow area is designated a wildlife reserve and under protection of Dubai Crown Prince and Defence Minister General Sheikh Moharruned bin Rashid Al Makhtoum. As the lagoon is still connected to the Arabian Gulf it has a tidal range of up to 1.5 m. The bottom of
12 Waders and other waterbirds in the United Arab Emirates lagoon is still connected to the Arabian Gulf it has a tidal range of up to 1.5 m. The bottom of the shallow part is sandy and muddy, and with low tide there are many large banks exposed (up to 150 hectares). In the south, treated sewage effluent, irrigation run-off and hypersaline water from a ground water pumping station run into the lagoon. In 1991, and again in 1993, a total of 30,000 small Black Mangrove Avicennia marina trees were planted along the southeastern and south side of the shallow part of the lagoon. Part of these trees are now growing slowly but successfully. Thc oldest planted mangrove formed bushy trees of up to 3 m high in spring 1994. Of the first planted trees most have died. Of the 10,000 trees recently planted thousands have died off as well, but several hundreds seem to be growing fairly well. The mangrove trees have significantly altered the intertidal micro-habitat and its invertebrate community (see chapter 5). For the sake of the mangrove planting along the eastern part the upper layer was scoured off and the benthic life destroyed. The surface of the scraped area is coarsely rippled because of machine tracks and tidal influence; water remains after the tide recedes and small pools have developed between the ripples, rich in green algae and fish fry. During medium high tides this area is only partly flooded. The area is surrounded by flat sabkha and low sandy parts and overgrown with salt tolerant flora. Many dirt tracks are criss-crossing the sabkha. In the eastern part of the area a dike has been made in 1993, separating the intertidal mudflats from the halophyte zone; only along the southwestern side the water can still enter part of the sabkha. A dust road runs all around the lagoon. On the southern end a short dike penetrates the mudflats. The tip is called the 'duck feeder', where Flamingos are being fed regularly. A series of binded lagoons have been created since. Flamingos are now fed in three places. The major high tide roosts are found on the scraped-off area opposite the police post, on the sabkha on the southwest side, between the end of the pipeline and the duck feeder, and on the sandy banks and island on the north side.
Other wetlands
The numbers refer to numbers on the map (Figure 4.1).
Jebel Dhanna lebel Dhanna lies about 270 km west of Abu Dhabi. The shore on the west side of lebel Dhanna can be reached following a track which turns west from the main road to lebel Dhanna. From the unpaved road there are some sand tracks, which come rather close to the low sand dunes bordering the beach. The west-facing shore is rather wide at low tide. The beach consists of hard sand with a layer of 2-1 0 cm of soft mud, and some rock flats along the low dunes. On some places there are patches of seagrass (Halodule uninervis and/or Halophila stipulacea). At low tide many puddlcs remain on the beach. There are old, hard layers of oil on the beach, partly covered with sand. On the north side a small harbour is present. Thc access to the northern tip of lebel Dhanna is forbidden. The east-facing side was only visited briefly during high tide. It is probably possible to continue driving along the shoreline on this east-facing side for some distancc (there are people living along the shore), but this was not tried because of the very low number of birds.
13 Description of the study area
Shaksa'eet al Ya'en This site lies 45 km west of the exit to Mirfa, close to Thumayri'yah. The coast was reached over a several kilometres long dike; there were two causeways with barriers to small islands. On both sides of the causeways there are mud flats. During our visit (in autumn) it was falling tide and waders were moving away from the shore. We did not try to get on the island because it was almost sunset.
Halat Jamilah At the area Halat Jamilah two sites were counted. There is a dike running through the huge sabkha from the mainland to a peninsula. From the point where the dike runs through the water, the west and the east side were surveyed for Broad-billed Sandpipers. On the west side an area of approximately 1 km was counted during high tide, on the east side the counted area was also about 1 km during falling tide. The shorelines on both sides of the dike were quite soft, especially on the east side, where small channels were dug out for unknown reason.
Ad Dab'iyyab The sideroad to Ad Dab'iyyah lies approximately 70 km west of Abu Dhabi. The peninsula (30 km long) is predominantly flat and mainly of sand, low calcareous rocks and extensive sabkha. Along the northwest side there is a low sand ridge with lots of garbage on the storm berm. There are several patches of seagrass. Along the storm berm there are numerous banks of hard weathered oil. Along the tideline there are extensive mud- and sandflats and natural Black Mangrove. Large areas of the coastline are difficult to visit because there are no roads, or unreliable roads through sabkhas. There is oil-related industry, and many areas are restricted. New (unpaved) roads are under construction. The island Bu Kushaysha (or Al Aryan) on the northeast side of Ad Dab'iyyah, which holds large stands of pristine looking mangroves, can not be reached. The islands Gassabi, Bu Shara, Al Gantur etcetera, all the way to Zubbaya, southwest of Ad Dab'iyyah, can be reached because all are connected by causeways.
Abu Dhabi Eastern Lagoon This lagoon, officially called Khor al Baghal, on the northeast side of Abu Dhabi city, is almost completely covered with fairly recently planted and natural Black Mangroves (several metres high). It is not possible to enter the area from the northeast side (except with a boat, although access is anyway restricted). During low tide there are narrow mudbanks bordering the mangrove.
Ras Ghanada This area differs from the others in that it consists of salt marshes with halophytie flora, whieh are intersected by tidal creeks. Fairly small natural mangrove stands are numerous along the creeks.
Khor al Beidah Northeast of the city of Umm al Qaiwain lies Khor al Beidah. The area, about 20 km long and 6 km wide, consists of a complex of creeks, intertidal mudflats, sandy and muddy islands with natural Black Mangrove, bordered by sabkha, salt marshes and sand dunes. It is possible to
14 Waders and other waterbirds in the United Arab Emirates drive along most of the eastern side on sand tracks, which can be reached from the main road. The northwest side can not be visited from land.
Jazirat al Hamra This area, north of Khor al Beidah and about 10 km south of the town of Ras al Khaimah, consists of a c. 15 km long shallow lagoon with mudflats and islets, bordered by a long sandbar on the seaside, and dunes and mudflats on the land side. Especially on the northeast side, high sand-dunes (30 m) provide an excellent overview of the area.
Ras al Khaimah East of the town of Ras al Khaimah a tidal inlet of about 4 square km is found, with large stands of mangrove. The area is accessible on foot only.
Khor al Khowair North of Ras al Khaimah, up to Khor al Khowair, mangroves with creeks are found. The area is rather difficult to visit due to a lack of roads.
Qurayyah/Wadi Safad The lagoon system north of Fujairah, measures about 500 hectares and has a mainly sandy bottom, but is muddy along the edges, with some bordering saltmarsh.
KhorKalba Khor Kalba lies about 12 km south of the town of Fujairah, The northernmost tip lies about three km north of the border with Oman, but the khor crosses the border. It consists of three muddy tidal inlets, stretching inland and running parallel to the coastline for about 5 km; the total area measures approximately 7750 hectares. From the easternmost channel an extensive saltmarsh runs inland. Along the channels up to 8 m high, old stands of Black Mangrove grow along the creeks. Unfortunately, the age of the mangrove trees is unknown. During low tide the area is visited by large numbers of people collecting shells and crabs Metopograpsus messor on the mudflats and in creeks.
Golf Course The Emirates Golf Course lies approximately 25 kilometres southwest from the city of Dubai. The area measures about 80 hectares and is one of the greenest spots in the wide surroundings. Because the plants are watered continuously, there is plenty of water for migrant birds. There are four lakes, of which two are fresh water lakes. An interesting spot for waders lies just beyond the fence, on the northeastern side: this place is saline and consists of puddles and reedbeds.
15 Intertidal macro-·invertebrate fauna
16 Waders and other waterbirds in the United Arab Emirates
5. INTERTIDAL MACRO-INVERTEBRATE FAUNA Ruurd Noordhuis & Abraham bij de Vaate
5.1 Introduction
During wader surveys in April and May 1995 high numbers of birds were found in Khor Dubai compared to other intertidal areas along the UAE coast. To interpret distribution, and to determine food choice of Broad-billed Sandpipers and other waders, macrozoobenthos was sampled during this period. Additionally, samples were taken in several other areas, enabling comparison of food availability. In intertidal areas in the Arabian Gulf a zonation of several communities may be present. Most persistent are a halophyte zone above the high tide level, a Macrophthalmus-zone between high and low tide level and a Cerithidea-zone down to the level of the lowest spring tides (Basson et al. 1981). Black Mangroves Avicennia marina may create an additional zone around high tide level. The Macrophthalmus- and Cerithidea-zone are especially important for waders. The burrowing crab Macrophthalmus depressus characterizes the first zone, but is replaced by the smaller Scopimera crabricauda if sediments are sandy. The mud snail Cerithidea cingulata characterizes the lower zone, accompanied by other species; among these the echiurid Ikeda taenioides is most peculiar. However, the distinction between the two zones is not always clear and differences in factors like exposurc may be more important in forming spatial patterns (lones 1986). In this chapter we describe the intertidal fauna of seven coastal wetlands in the United Arab Emirates, and the southern half of Khor Dubai in particular.
5.2 Methods
Macrozoobenthos was sampled using a plastic corer with a diameter of 56 mm. At each site three samples to a depth of 15 cm and a total area of 221.67 cm2 were taken. Additional information on gastropods and crustaceans was gathered from larger areas by pegging out a metre quadrat. Samples were sieved through a sieve with a mesh width of 0.5 mm and stored in 6% formaldehyde. The animals in the samples were collected in the laboratory using a stereo microscope and identified according to lones (1986) and Basson et al. (1981) or by specialists (molluscs, annelids). Additional samples of the most abundant species were collected in order to derive size-weight equations, from which biomass was estimated. Dry mass was determined after drying the animals for 48 hours at 75°C, ash-free dry mass after six hours at 450°C. Additional data on biomass of Nereidae were gathered on 5 and 7 May by sieving all fragments from 20 sediment samples (area of 0.12 m2 each) along a transect across the central part of Khor Dubai (Figure 4.2). Three sites were selected for regular sampling (Figure 4.2, site A, B and C). These sites were sampled three times: on 10-11 April, 28 April and on 4-5 May. Six other locations along the Emirates' coast were visited during the period 13 April - 1 May: Jcbel Dhanna, Ad Dab'iyyah, Ras Ghanada, Khor al Beidah, lazirat al Harnra and Khor Kalba (Figure 4.1). On these locations samples were taken only once (one site per location).
17 Intertidal macro-invertebrate fauna
6 central sandflats • southern mudflats 5 eastern mudflats
Cl> ca ::l 4 "C :~ "C .S; ..... 3 ...0 Q) .0 E 2 ::l C
o 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 jaw length (mm) Figure 5.2 Frequency distribution of jaw lengths (in mm) of Nereidae in samples from KhorDubai, 5 May 1995.
Elsewhere on the central flat hermit crabs (c! Diogenes) were common in tidal pools while in the higher, northeastern part the burrows of Scopimera crabricauda reached densities of 100/m 2 • This area had similar sediments on the higher grounds between the mangroves of the eastern plantation, where Scopimera crabricauda was accompanied by Fiddler Crabs Uca lactea.
Site C was situated in an area east of the mangrove plantation in the eastern part. This area is more or less isolated between the mangroves and the eastern dikes and piers. It is used by waders as a high tide refuge during the lower high tides, but also for foraging. The sediment was characterized by a silty top layer on a thick layer of shell fragments. The invertebrate community was quite different from that in the other sites. Densities ofNereidae were low but the smaller annelids were numerous; enormous densities of Sabellidae formed a one centimetre thick crust of fused tubes 011 top of the sediment. Ostracods were also abundant. Many small tidal puddles were present in which fish fry often accumulated. The mud snail Pirenella conica reached enormous densities, especially around the puddles. It also occurred in high numbers on and underneath the algal mat between the mangroves.
20 Waders and other waterbirds in the United Arab Emirates
8 south east .... north west
3
2
o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 location number
Figure 5.3 Biomass (in g ash free dry mass per m2) of Nereidae at 20 sites along a transect across the central part ofKhor Dubai (Figure 4.2), sampled at 4 and 7 May 1995.
Body mass in relation to body size The relations between size (L, in mm) and ashfree dry mass (AFDM, in g) was established for the following species:
Dosinia sp. AFDM = 0.00003 * L 2.75 r = 0.969 (shell width) Tellina arsinoensis AFDM = 0.00002 0+ L 2.53 r = 0.9232 Pirenella conica AFDM = 0.0002 * L 1.57 r = 0.57 (shell hight) Cerithidea cingulata AFDM = 0.00001 • L 2,73 r= 0.9603
Nereidae (both species) AFDM = 0.0176 * L;;;;:309 r = 0.8452
Lworm = 10.277 * L)0;.86 f=0.535,F 1•19 =47.3,p<0.OOl,n=21
2 AFDM = 0.249 * L~!06 r =O.714,F1•19 =21.8,p<0.001,n=21 (Figure 5.4) in which AFDM = ash-free dry mass in mg; Lmax = stretched wonn length, in cm; LJaw = jaw length.
The fonnulas of Nereidae were used to calculate AFDM from estimated wonn lengths (see also figure 5.4 and chapter 6.4).
21 Intertidal macro-invertebrate fauna
Mean AFDM was established for: Diogenes sp. 0.023 g (n = 13); Capitella capitata 0.047 mg (n = 130); SabeIJidae 0.034 mg (n = 90).
Density changes The three sampling dates at Khor Dubai spanned three and a half weeks, during which several thousand waders had been foraging on the flats. Densities of many of the most abundant species had decreased during that time. This seems to be the case with the molluscs Pirenella and Dosinia, with ostracods and with Sabellidae. Nereids and Capitella did not show a clear decrease in density. As a result of selection of larger animals by predators, nereid biomass may have decreased in spite of unchanged densities. As biomass of nereids was estimated using the same equation for all sampling dates, such a decrease would not be visible in Table 5.2.
Other areas
Jebel Dhanna No sediment sample was taken, but sediment seemed to be generally sandy with silty patches. Macrozoobenthos was relatively rich in nereids. The annclids Paraonis sp. and Ophelina sp., typical of sandflats (Basson et al. 1981), were more abundant than anywhere else (Table 5.3). Bivalves on the other hand were hardly found, and gastropods were not very numerous either.
Ad Dab'iyyab In the western part of this area extensive mature mangrove stands are present. Here sediment is muddy, but samples were taken in the more open, eastern part, where the sediment is sandy. Mean nereid densities were relatively high but distribution seemed to be patchy, and densities of other annelids were low. Several species of bivalves were found. Among these was the small mytilid Brachidontes variabilis, which occurred locally in high densities (banks) from the lower end of the intertidal zone downward (Table 5.3). The banks were also inhabited by a variety of annelids and small crustaceans.
Ras Gbanada This area differs from the others in that it consists of salt marshes with halophytes, intersected by tidal creeks rather than consisting of sand- and mudflats. Mangroves, although not yet mature, can be found along the creeks at many sites. Samples were taken partly between the mangroves, and the large variety of species found showed similarity to that of the samples from the mangrove forest of Khor Kalba. The area was particularly rich in mollusc species, of which the bivalve Pillucina jischeriana reached very high densities. Noteworthy were also the high densities of chironomid larvae and the occurrence of the echiurid Ikeda laenioides (Table 5.3).
Khor al Beidah Extensive area of mud-, sand- and saltflats. Samples were taken at a sandy part of the area, where fairly large densities of molluscs (gastropod Pirenella conica and bivalves Tellinll arsinoellSis and Dosinia sp.) were found. No nereids werc found, but Capitella capitata was found in densities only matched by those at Khor Dubai (Table 5.3).
Jazirat al Hamra This area consists of shallow lagoons protected by a mudbank. The area is important for waders (especially Terek Sandpipers; Aspinall1995) and other migratory birds.
22 Waders and other waterbirds in the United Arab Emirates
The site where samples were taken was muddier than in the other areas, excepting Khor Dubai. At this site densities of macrozoobenthic species were extremely low, except for Dosinia sp., which reached higher densities than at any of the other sampling sites. Strangely, annelids were almost absent from the samples. Around high tide level small burrowing crabs Scopimera crabricauda and Uca lactea were numerous (Table 5.3).
Khor Kalba This area is separated from the others by the eastern mountains, and borders the Gulf of Oman instead of the Arabian Gulf. Several species of invertebrates encountered at this site were not found in any of the other areas. Mature mangrove dominates the area and encloses a small intertidal lagoon system. Similar to Ras Ghanada a relatively large number of invertebrate species was found here. Nereids reached higher densities than in the other areas, but the smaller annelids were less abundant. High densities were also reached by the gastropod Clypeomorus bifasciata (while Pirenella conica, found at almost all other areas, was absent) and the bivalve Pillucina jischeriana, another characteristic shared with Ras Ghanada (Table 5.3). Several species of crabs and hermit crabs inhabit Khor Kalba. Many of these, e.g. Fiddler Crabs Uca lactea, burrow in the sediment between the mangroves and are preyed upon by White-collared Kingfishers.
mass (mg AFDM) 100
50 • • •• • 30 • • • • 20 • •
10 • • 5 •
3L-__~ __~ __~ __-L ____ -L ____ ~ __~ __~ __~~ 6 8 10 12 14 16 18 20 22 maximum body length (cm)
Figure 5.4 Body mass of worms Nereidae (in mg ash free dry mass) as a function of body length (cm).
23 Intertidal macro-invertebrate fauna
5.4 Discussion
The species composition found at Khor Dubai is more or less similar to that found by Ismail (1992) and Platt (1994), but there are some differences. Platt (1994) does not mention any polychaetes other than nereids, of which he found two (unidentified) species. He found by far the highest densities at mid-tide level, which may correspond to the increase in biomass along our transect in the central part of the lagoon. Ismail (1992) found just one nereid, which he identified as Leptonereis sp. Densities of nereids found by both authors are within the range found during our project. Ismail (1992) did find other polychaetes, of which Polydora (two species) was most abundant. Capitella capitata on the other hand reached lower densities than in our study, whereas Sabellidae were not found at all. Compared to the other areas, the sediment at Khor Dubai is rather muddy. The macrozoobenthos of Khor Dubai was relatively poor in species and several key species like Nereidae, Tellina arsinoensis and Dosinia sp. reached only moderate densities. Small annelids however, particularly Capitella capitata and, locally, Sabellidae, reached densities much higher than in the other areas. According to Ismail (1992), the presence of Capitella capitata and Polydora sp. may indicate organic pollution as a result of sewage discharge into the area. Until a few years ago, the city of Dubai dumped its sewage into the creek. The resulting enrichment probably still influences the composition of the invertebrate fauna today. Capitella capitata was found in much lower densities at most of the other sampling sites, while Polydora sp. was not found anywhere but at Khor Dubai. However, more detailed studies of species composition in relation to sediment composition are necessary to be able to draw further conclusions.
24 Table 5.1 Macrozoobenthos from core samples and number of individuals per m2, Khor Dubai, United Arab Emirates, April-May 1995. The total area of each sample was 221 .67 cm 2.
site sand central mud south mud/mangrove east mangrove south date 10/4 28/4 415 11/4 28/4 515 10/4 28/4 515 1114 28/4 515
Mollusca Pirenella conica 9009 6532 1036 Dosinia sp. 90 225 270 180 90 1892 I~f} ~ Arthropoda § s::... Diogenes sp. 45 <:> Scopimera crabricauda 90 So '"'< Crustacea sp. 90 :;: Ostracoda 315 135 270 90 45 11802 1261 1081 1622 ~ '< Chironornidae 45 ~ ::;- Simulidae 45 t,l t:- Vl Muscidae 135 s· So Annelida '" ~ Capitella capitata 4865 4685 1171 856 3153 721 6757 1667 946 270 405 ;:;: Polydora sp. 856 45 '"s::... ::t... Sabellidae 541 85315 30856 6802 2973 405 '< I:> Nereidae 225 495 495 360 90 495 135 180 180 541 405 676 ~
~::; ~ '"c., Table 5.2 Estimated biomass in g ashfree dry mass per m\ Khor Dubai, United Arab Emirates, April-May 1995. The total area of each sample was 221.67 cm 2 . Ashfree dry mass was estimated using I) size distribution from each sample, 2) average value per individual or 3) size distribution from combined samples per area.
site sand central mud south mud/mangrove east mangrove south date 10/4 28/4 4/5 1114 28/4 5/5 10/4 28/4 5/5 1114 28/4 5/5
biomass:
Pirenella conical 51.918 30.433 5.399 Dosinia Sp.1 2.214 0.466 8.854 14.154 2.214 62.042 Diogenes Sp.2 1.041 :? ~ Capitella capitata2 0.224 0.216 0.054 0.036 - 0.131 0.039 0.361 0.089 0.039 0.011 0.017 ::t Sabellidae2 0.018 2.910 1.053 0.232 0.101 0.014 3 ~ Nereidae 1.246 2.740 2.740 7.883 1.971 10.838 3.424 4.566 4.566 11.846 8.868 14.802 ::l others 0.044 2.072 0.004 0.004 0.011 I::) "9 d 7hQ ? Q<;'; ? 7Qd In d7<; 11 R?'i ?'i 1?1 IS· ______hn .509 36.417 10.286 __ 74.039 8.893 14.819______..: ~ :to~ta:I~ ~~~~~~~~~~~~~~~~J1~ ~~~~~~Ql~ ~~~~~~~~ .... '"~ <:>- ~ is s:: ::. I::) Table 5.3 Macrozoobenthos from core samples (c, first column) and gastropods and crustaceans from additional samples taken from the top layer of sediment (t, second column) in number of individuals per m2, United Arab Emirates, April-May 1995. The total area of each sample was 221.67 cm 2 • site Jebel Ad Dab'iyyah Ras Khor Dubai Khor al Jazirat al Khor Dhanna Ghanada Beidah Hamra Kalba date 24-4 16-4 13-4 south central east 17-4 15-4 1-5 c c c c c c c c c Cnidaria/Anthozoa Actinaria 180 16 I~ ~ Echiurida lkeda taenioides + + I~ ~ Cls:. Mollusca/Gastropoda t\)... Cerithidea cingulata 90 123 33 135 54 45 96 90 92 '!'! ~ Pirenella conica + - 1125 14 - 5526 17984 361 252 ;;;... Clypeomorus bifasciata 15 + 45 3 + 13 11 992 292 <:>-
!,J Mitrella blanda 12 (+) 90 11 13S ~ --.J Nassarius acicularius + (+) '":i ' s:. Monodonta sp. 3 t\) Planaxis sulcatus + ~ Oliva sp. 45 ~. 45 ~ Hydrobia sp. :>.. ~ MolluscalBivalvia <:>- Brachidontes variabilis 135 ~ Tellina arsinoensis 226 180 226 ~. t\) Tellina sp. B 45 '" Gari cf occidens 45 cf Spisula 45 Dosinia sp. 45 271 271 225 30 30 857 947 45 Pillucina fischeriana 45 1624 180 Venerupis sp. 45 Laternula anatina 45 Table 5.3 ~continued2 site Jebel Ad Dab'iyyah Ras Khor Dubai Khoral Jazirat al Khor Dhanna Ghanada Beidah Hamra Kalba date 24-4 16-4 13-4 south central east 17-4 15-4 1-5 c c c c c c t c c c Arthropoda/CrustacealDecapoda Diogenes sp. 68 15 95 - 31120 496 47 Paguridae indet. + Scopimera crabricauda + 148 30 - 19/98 50 135 Uca lactea + + + Macrophthalmus depressus + +
Liocarcinus sp. + S' Callinecles sapidus + + ~ Ebalia sp. 1 (+) (+) 5 (+) ~ Crustacea sp. 541 1667 30 90 ~ ::l Ostracoda 135 150 4715 90 \:) .... Chironomidae 1577 15 "<':l IV 00 Simulidae 15 ;;" ~ '".... AnnelidalPolychaeta Capitella capitata 315 405 315 1336 3574 3048 2027 135 Polydora sp. 15 285 ~ \:) Sabellidae 1441 180 - 40991 45 45 § Nereidae 1081 766 631 315 405 165 1126 ~\:) Scololepis sp. 45 45 Paraonis sp. 1532 Ophelina sp. 1441 450 Po]ycbaeta indet. 1535 360 135 Maldanidae sp. 225 cl Heteromastus sp. 450 cl Terebellomorpha 270 Sy\lidae sp. 495 Goniadidae sp. 315
number of species 8 16 8 11 17 24 7 7 8 17 10 15 5 11 14 18 Waders and other waterbirds in the United Arab Emirates
6. W ATERBIRD STUDIES
6.1 NUMBERS Guido Keijl & Paul Ruiters
Methods
Birds were counted on foot and by car at regular intervals, using binoculars and telescopes. In spring 1995 Khor Dubai was counted completely onCe every three to six days; the other areas were counted more opportunistically (for counting dates see Appendix 4). Visibility and weather were usually good, except during the counts of Jebel Dhanna and Merawah in spring, when visibility was rather poor. The count of Khor Dubai on 5 October 1994 failed because of strong onshore wind, which pushed up the water level to such an extent that many birds were forced out of the area. The count of Khor Dubai on 24 April failed completely due to a short but heavy thunderstorm. Only Merawah, the Emirates Golf Course and Khor Dubai could be counted completely. Other areas are either too extensive and difficult to reach to cover completely, or are private property and therefore inaccessible. Most of the coast south of Khor Dubai all the way to the border with Saudi Arabia, for instance, is either private property (all islands are owned by the sheikh or other members of the royal families) or just inaccessible due to quick sands, lack of roads, etcetera. In most cases the areas were counted as long as (dust) roads, tide and time permitted. Data from January 1995, collated by Simon Aspinall, are added to give a more complete picture of the use ofwetlands in the UAE and species composition. Extrapolation of numbers of waders (see paragraph 6.3) was done by measuring the counted surface and multiplying this with the average density of number of waders per hectare to the total available surface of tidal area. For the latter the surface as indicated on Admiralty Marine Charts (scale: 1:125.000 and 1:350.000) was measured. Data for autumn 1994 and spring 1995 were calculated separately. Because of the very high density of waders in Khor Dubai this figure was left out from the calculation of the average density.
Results
Of all wetlands visited, Khor Dubai held most birds in autumn, winter and spring (Table 6.1, Appendices 1-5). The only exception was Khor al Beidah in autumn (1994), where a single flock of approximately 40,000 Socotra Cormorants made up 96% of the total number of birds counted there (Appendix I). Apart from this flock, just over 1500 other waterbirds were counted in this area.
29 Waterbird studies
Jazirat al Hamra Khor al Beidah
Shaksa'eet al Ya'en G) ~ JebelDhanna Abu al Abyadh \
e·...... · ...... · ...... · ...... " · Ur. B:I :::am Ad Dab'iyyah
o ducks, grebes • Flamingo EJJ waders ;g gulls, terns D herons, cormorants, Spoonbill
Figure 6.1 Relative composition of five hird groups in ten counting areas in autumn 1994 in the UAE. See also Appendix I.
JO Waders and other waterbirds in the United Arab Emirates
Khor al 8eidah Jazirat al Hamra
Khor Duba; .l ~ "ilgw ..c%TI. I Bel Ghelam \
\ Ad Dab'iyyah G AI Ghar
• Flamingo o herons, cormorants, Spoonbill • gulls, terns EJ waders
Figure 6.2 Relative composition of four bird groups in eleven counting areas in spring 1995 in the UAE. See also Appendix 3.
31 Waterbird studies
Waders were the dominant bird group in autumn and spring in almost all areas: autumn 1994: 51-98%, (Figure 6.1), spring 1995: 85-99% (Figure 6.2; Table 6.2). However, along the east coast the main bird groups consisted of gulls and terns in all seasons: autumn 1994: 1% gulls, 94% terns winter 1995: 90% gulls, 8% terns spring 1995: 72% gulls, 27% terns. In winter the overall situation was different, because in most areas gulls were most numerous (waders per area for all areas 0-97%). If areas which were not counted in autumn nor in spring (for instance several off-shore islands) are excluded, the figures for waders per area are 34-97%. In Khor Dubai the bird population in winter consisted of 56% waders and 38% gulls (Figure 6.3). In autumn 1994 a continuous flow of thousands of terns was observed along the east coast; these birds had apparently been feeding in Dibba Bay and were following the coast southwards. They are not included in the counting results. Spring migration patterns for a selected number of species are presented in Figure 6.4, numbers of all bird species per area in Appendices 1-5. Below, a short discussion of numbers per bird group is given.
Table 6.1. Total number of waterbirds in wetlands in the United Arab Emirates which were censused in September-October 1994, January 1995 and April-May 1995. The percentage of the number of birds per area in autumn and spring is presented relative to the number of birds in winter. The flock of 40,000 Socotra Cormorants in Khor al Beidah in autumn was subtracted from the count.
autumn 1994 % winter 1995 spring 1995 % area Jebel Dhanna 503 261 193 166 86 Abu al Abyadh 1394 20 6922 2766 40 Ad Dabi'yyah 2041 102 1998 755 38 Bel Ghelam 84 11 802 459 57 Golf Course 174 76 230 107 47 Khor Dubai 6001 28 21,289 4933 23 Khor al Beidah 1526 24 6451 1362 21 Jazirat al Hamra 1163 50 2313 284 12 Dibba-Khor Kalba 834 13 6396 4161 65
total / average % 13,720 29 46,594 14,993 32
32 Waders and other waterbirds in the United Arab Emirates
Table 6.2. Comparison of seven bird groups in a selected number of wetlands in the United Arab Emirates between autumn 1994, winter 1995 and spring 1995.
connorants herons & Flamingo ducks and waders gulls terns total S~oonbill grebes Ad Dabi'yyah autumn 1 32 0 0 1924 45 41 2043 winter 2 12 0 0 1887 73 24 1998 spring 0 2 0 0 746 0 7 755
Khor Dubai autumn 462 1224 14 4192 1149 59 7101 winter 215 209 372 404 11,909 8146 20 21,275 spring 2 526 416 2 4204 92 99 5339
Khor al Bcidah autumn 40,000 150 0 0 1305 11 60 41,526 winter 0 7 43 0 1886 43 93 2072 spring 7 22 95 0 1063 0 30 3289
Jazirat al Hamra autumn 47 0 0 737 345 36 1166 winter 3 99 0 5 1514 567 125 2313 spring 0 14 0 0 267 2 1 284
Dibba-Khor Kalba autumn 0 12 0 3 171 10 788 984 winter 7 22 0 0 121 5452 792 6394 s~ring 0 0 0 0 45 3004 1112 4161 Waterbird studies
---- -
autumn winter
spring
D cormorants, grebes herons, spoonbill ducks §D waders •EJ gulls ~ flamingo 0. .. . terns
Figure 6.3 Relative composition of seven bird groups in Khor Dubai in autumn 1994, winter 1995 and spring 1995. See also Table 6.2.
34 Waders and other waterbirds in the United Arab Emirates
Khor Dubai In autumn 1994 Khor Dubai was counted completely only on 29 September (Appendix 1); the maximum number of birds was 5789. On this date, species composition was slightly differing from that in spring, the most common wader species being Dunlin (1700), Kentish Plover (700), Bar-tailed Godwit (249), Grey Plover (225) and Curlew Sandpiper (220). In January 1995 bird numbers were much higher than in either autumn or spring: a total of over 21,000 birds was counted. Most numerous were Dunlin (5330), Yellow-legged Gull (4200), Black-headed Gull (3700), Lesser Sandplover (1474) and Kentish Plover (1325) (data per S. Aspinall and C. Richardson). In spring, highest numbers of waterbirds were present in Khor Dubai on 28 April, when almost 5000 were counted. During this count waders made up 85% of the total number of birds. The most numerous wader species were Curlew Sandpiper (1660), Lesser Sandplover (1263), Grey Plover (478), Bar-tailed Godwit (461) and Little Stint (374). Peak numbers for all these species fell between 18 April and 1 May. Migration peaks of waders roughly agreed with numbers counted at Ras Ghanada (Appendix 5).
Herons are relatively scarce in Khor Dubai (less than 10% of the total number of birds), even though the area is very rich in small fish. Only Grey Herons were counted in hundreds (366 in late September 1994). Numbers of the second-most numerous heron species, Western Reef Egret, were much lower, with highest numbers on 29 September (65) and on 18 May (12).
Gulls are mainly winter visitors to Khor Dubai (38% of the total number of birds present), while terns are most common (although occurring in small numbers only) in spring. Yellow-legged Gulls (1100 on 29 September 1994, 4200 in January 1995), Black-headed Gulls (3700 in January 1995), Slender-billed Gulls (244 in January 1995, 97 on 12 April), Sandwich Terns (95 on 25 April) and Caspian Terns (54 on 12 April) were the most common species.
In spring 1995, Flamingos were just arriving in April in Khor Dubai and numbers peaked on 28 April (8% of total number of birds present). In autumn 1994 124 individuals were counted, while in winter 372 stayed in the area. Most Flamingos are usually present in winter and during the years between 1985 and 1991 peaks numbers of over 2000 were counted in this area (Platt 1994), but since then numbers declined for unknown reasons (Aspinall 1996a). Numbers of Flamingos in Khor Dubai are kept artificially high by regularly feeding pellets at the duck-feeder (at least several times a week). The observed increase during April corresponded to a slight increase of Flamingos in Khor al Beidah between 17 April and 6 May and thus probably reflected a genuine migration of birds originating from Iranian or possibly Russian colonies.
35 Waterbird studies
Other areas Even though most areas could not be covered completely, it was obvious that birds occurred in much lower concentrations. On 5 October 1994, a seemingly endless flock of Socotra Cormorants flew inward in Khor al Beidah (Umm aI Qaiwain; Appendix 1). This massive concentration no doubt originated from the nearby colony at Sinaiya, which held over 15,000 pairs in 1994 (Aspinall 1996a). All areas other than Khor Dubai held a few hundred birds per species in autumn 1994 at maximum. In spring, concentrations of a few species (e.g. Lesser Sandplover at Khor al Beidah, 679 individuals; Grey Plover at Khor al Beidah, 178; Bar-tailed Godwit at Khor al Beidah, 491 and at Merawah, 566; Sooty Gull at KhaT Kalba and the beach to the north, 3000; Common Tern at Khor Kalba, 1000; White-cheeked Tern at Khor Kalba, 200) were found in several wetlands, mainly at Khor al Beidah and the east coast close to Khor Kalba.
Broad-billed Sandpipers Within the UAE Khor Dubai is apparently still the principle area for Broad-billed Sandpipers, with numbers building up in autumn and the largest numbers present mainly in winter (Table 6.3).
Table 6.3 Numbers of Broad-billed Sandpipers at KhaT Dubai and other wetlands during autumn 1994, January 1995 and spring 1995. For Khor Dubai in spring only the maximum number is given; other numbers in this area in spring can be found in Appendix 4.
date site number 29 September 1994 KhorDubai 220 5 October 1994 Khor Dubai 150 (incomplete count) January 1995 KhorDubai 509 18 April 1995 KhorDubai 63
2 October 1994 Halat Jamilah 22 3 October 1994 lebel Dhanna 52 10 April 1995 Ras Ghanada 6 14 AEril 1995 AlGhar
Contrary to the large numbers found in autumn 1986 and 1987 nowadays a much smaller number uses the area. A minority of the Broad-billed Sandpipers observed during autumn 1994 was moulting flight feathers.
36 Waders and other waterbirds in the United Arab Emirates number number 100 400 Ringed Plover Kentish Plover 80 300 60 200 40 100 20
0 0 10 20 30 10 20 10 20 30 10 20 April May April May number number 1400 200 Lesser Pacific Golden Plover 1200 Sandplover 1000 150 800 100 600 400 50 200 0 0 10 20 30 10 20 10 20 30 10 20 April May April May number number 500 25 Grey Plover Sanderling 400 20
300 15
200 10
100 5
0 0 10 20 30 10 20 10 20 30 10 20 April May April May
Figure 6.4 Migration pattern of a selected number of species in spring 1995 in Kh or Dubai, UAE.
37 Waterbird studies number number 400 2000 Little Stint Curlew Sandpiper 300 1500·
200 1000
100 500
0 0 10 20 30 10 20 10 20 30 10 20 April May April May number number 140 70 Dunlin 120 60 Broad-billed Sandpiper 100 50 80 40 60 30 40 20 20 10 0 0 10 20 30 10 20 10 20 30 10 20 April May April May number number 500 140 Bar-tailed Godwit 400 120 100 300 80 200 60 40 100 20 0 0 10 20 30 10 20 10 20 30 10 20 April May April May
Figure 6.4 Migration pattern of a selected number of species in spring 1995 in Khor Dubai, UAE.
38 Waders and other waterbirds in the United Arab Emirates
number number 50 50 Turnstone Yellow-legged Gull 40 40
30 30
20 20
10 10
0 0 10 20 30 10 20 10 20 30 10 20 April May April May
number number 100 60 Slender-billed Gull Caspian Tern 80 50 40 60 30 40 20 20 10 0 0 10 20 30 10 20 10 20 30 10 20 April May April May
number number 100 460 Sandwich Tern Flamingo 80 440 - yA 60 420 400 40 - 380 20
0 I 10 20 30 10 20 10 20 30 10 20 April May April May
Figure 6.4 Migration pattern of a selected number of species in spring 1995 in Khor Dubai, UAE.
39 Waterbird studies
Discussion
Numbers and densities of waders
It goes without saying that surveying periods were too short, both in spring and in autwnn, to present complete migration patterns for each species, even in Khor Dubai. Most Dunlin populations, for example, migrate earlier in spring and during April we were apparently witnessing the end of Dunlin migration. Also, between 9-11 September 1994 Khor Dubai held about 8700 waders (S. Aspinall pers. comm.), while only two weeks later this number had dropped to almost 5800. We do not have information on turn-over rate, but observations in spring 1995 on migrating waders in the evening made clear that turn-over rates can be high. Khor Dubai held the highest numbers of waders, even though it is one of the smallest tidal areas within the UAE. (Note that the mudflat area available to birds is slightly larger than indicated by Evans (1994)). The fact that wader numbers were lower in spring than in January shows that many birds use the area as a wintering site. However, migration takes place through the area as well, as can be seen by comparing numbers from autumn 1994, January 1995 and April-May 1995: apparently, in many species the wintering population leaves before spring migration of birds having wintered further south takes place. In Little Stint, for instance, the wintering population numbered 458 individuals. On the first count during the spring project only 77 were present. This number rose to 374 on 28 April, after which the number dropped quickly in May. A roughly similar pattern, with higher numbers in winter than in April, and a migration peak during late April or May, is shown by Bar-tailed Godwit, Lesser Sandplover, Pacific Golden Plover and Grey Plover. In Kentish Plover numbers during winter were also much highcr than in spring; the numbers however rose during April and May, possibly because failed breeders entered the area and local breeding birds appeared after their eggs hatched. It is interesting to note that a similar migration pattern was shown by several species elsewhere in the Middle East (Evans & Keijl 1992a, Keijl et al. 1992, Hirschfeld 1994), suggesting that many species, although probably showing site fidelity, are migrating in a broad front. Richardson et al. (1994) sum up nine species which occur in internationally important numbers in Khor Dubai (Grey Heron, Ringed Plover, Kentish Plover, Lesser Sandplover, Greater Sandplover, Grey Plover, Broad-billed Sandpiper, Redshank and Black-Headed Gull). All occur in winter or on migration. Aspinall (1996a) also designates Kentish Plover as a priority breeding species, since numbers in Khor Dubai exceed the 1%-level, not only during winter but also during the breeding season. Considering our counting results it seems as if the area has become less attractive to waders, as numbers did not exceed those mentioned by Richardson et al. (1994) for any of the species mentioned above, either in autumn or in spring. A possible explanation for this phenomenon could be that the circumstances for macrozoobenthos in the intertidal area have deteriorated.
In order to know how many waders were present in the UAE during late September early October 1994 and late April-early May 1995, the average density of waders in a number of tidal areas was calculated (Table 6.4), after which this number was extrapolated to reach a total number of waders in the UAE. Densities could not be calculated from some areas as the surface of the area counted was not establishcd, the number of waders present in these coastal
40 Waders and other walerbirds in the United Arab Emirates areas was simply added to the extrapolated number, thus giving a minimum estimate of total number of waders in the wetlands at that particular time. The density of birds in Khor Dubai was much higher than anywhere else; because of this, this figure was left out for calculating the average density. The coast length of the UAE (excepting the east coast) measures approximately 450 km. The total surface of intertidal area in the UAE amounts to 2649 square kilometres (measured from Admiralty Marine Charts). In autumn, 168 square kilometres of this (6.35%) was surveyed, in spring 126 square kilometres (4.77%).
Table 6.4 Area censussed (in hectares), number of waders counted (n), and density (n/hectare) in a number of coastal wetlands in the UAE in autumn 1994 and spring 1995. These figures were used to calculate the total number present in the entire coastal UAE; the number of waders from non-density counts in coastal areas was added to give the total (minimum) number of waders in autumn and spring.
site name surface number of density waders AUTUMN lebel Dhanna & Shaksa'eet al Ya'en 1813 861 0047 Ad Dab'iyyah & lumai1ah 6517 2641 0041 KhorDubai 197 4192 21.27 Khor al Beidah 5194 1305 0.25 lazirat al Hamrah & Khor al Khowair 3283 737 0.22
Total number in autumn: 91,562
SPRING lebe1 Dhanna 882 142 0.16 Ad Dab'iyyah & lumai1ah 2499 746 0.30 Ras Ghanada 1274 886 0.70 Khor Dubai 197 4204 21.33 Khor al Beidah 5194 1153 0.22 lazirat al Hamrah & Khor al Khowair 2793 267 0.10
Total number in spring: 71,123
Uttley et al. (1988) counted "at least 40,000" waders in autumn in the UAE north of Abu Dhabi (of which about 10,000 or 17,000 in Khor Dubai; the real figure does not become clear from their publication). The densities are comparable to the figures found by Zwarts et al. (1991) in muddy habitat in winter in Saudi Arabia (ranging from 0 to 6.19 birds per hectare, 0.89 on average), except for Khor Dubai, where the densities in spring and autumn are much higher. In winter the density is higher still (60.4) than in either spring or autumn and much higher than in Saudi Arabia. However, one arca in Saudi Arabia held 46.2 waders per hectare in winter 1986 CL. Zwarts in Evans & Keijl 1993b). Two other areas in Saudi Arabia in spring 1992 held 1.5 and 22.9 waders/ha in April-May 1991 (Evans & Keijl 1993b). Thc density of waders in Barr al Hikman, an intertidal area along the coast of Oman, in winter was 11.14 birds per hectare (Green et al. 1992). Zwarts (1988) compares winter densities of waders between areas along the East Atlantic Flyway. This review shows that the number of waders per hectare may
41 Waterbird studies fluctuate largely, also at a comparable latitude, and are generally higher than found in the UAE, but lower than the density at Khor Dubai (5.0-41.6 waders per hectare between 10-40 ON). Naturally, numbers in spring and autumn can fluctuate largely due to migration; therefore, the estimates given here should be regarded as a minimum number present at that particular moment. The turn-over of waders in these arcas is not known. For species occurring in most areas the total number present in the UAE during autumn and spring is calculated (Table 6.5). When we compare the numbers found staging in the UAE with the 1%-level for the non-breeding populations or the absolute minimum 1%-estimate (Evans 1994, Rose & Scott 1994), the UAE holds more for all species, except for Ringed Plover, Little Stint (autumn), Sanderling (autumn) and Curlew Sandpiper. For Curlcw Sandpiper the numbers are only just below the 1%-level. There is no population estimate for Whimbrel for this part of the world.
Table 6.5 Extrapolated number of waders occurring in (almost) all tidal areas counted (1) in the same areas as indicated in Table 6.4. In column 2 the absolute number of waders in Khor Dubai are added to column 1.
spring autumn 1% 1 2 1 2 non-breeding Oystercatcher 1299 1337 2175 2289 250 Ringed Plover 0 54 299 408 2000 Kentish Plover 2787 3049 10,906 11,606 250 Lesser Sandplover 17,893 19,156 12,466 12,513 250 Grey Plover 6830 7273 3057 3282 440 Sanderling 2577 2598 1150 1157 1200 Little Stint 733 1107 630 830 1200 Curlew Sandpiper 2011 2979 2600 2820 3100 Dunlin 9470 9511 21,811 23,511 1500 Bar-tailed Godwit 14,938 15,322 6950 7199 1000 Whimbrel 440 440 252 252 Curlew 293 298 1466 1507 250 Redshank 1634 1640 8589 8782 100 Greenshank 545 548 599 622 250 Terek Sandpiper 2430 2534 1749 1758 440 Tumstone 1278 1307 1340 1361 500
42 Waders and other waterbirds in the United Arab Emirates
Numbers and densities of Grey Herons and Western Reef Egrets
Grey Herons and Western Reef Egrets were the only herons encountered in most wetlands. Therefore densities for these two species were calculated in a similar way as was done for waders (Table 6.6). Also, an estimate was made for numbers present in autumn and spring.
Table 6.6 Total number of Grey Herons and Western Reef Egrets counted, and density (n/hectare) in a number of coastal wetlands in the UAE in autumn ]994 and spring 1995. These figures were used to calculate the total number present in the entire coastal UAE. In the total number for the UAE the numbers along the east coast were also included.
area number of density herons AUTUMN lebel Dhanna & Shaksa'eet al Ya'en 13 0.01 Ad Dab'iyyah & lumailah 42 0.Q1 Khor Dubai 431 2.19 Khor at Beidah 150 0.03 Jazirat al Hamrah & Khor al Khowair 45 0.0]
Total number in autumn: 4387 Grey Herons 719 Westem Reef Egrets 3668
SPRING lebel Dhanna 4 0.00 Ad Dab'iyyah & lumaiJah 2 0.00 Ras Ghanada 7 0.01 Khor Dubai III 0.56 Khor al Beidah 22 0.00 Jazirat al Hamrah & Khor al Khowair 14 0.00
Tota] number in spring: 1]62 Grey Herons 216 Westem Reef Egrets 946
The percentage of herons per area in spring and autumn was fairly similar. The densities show that Khor Dubai held most herons in spring and in autumn. This number consisted mainly of Grey Herons: in spring 46% of the Grey Herons (of the total number in the UAE) wa~ counted here, and in autumn 51 %. A few Grey Herons oversumrner in Khor Dubai (Simon Aspinal pers. comm.). Khor al Bcidah held 65 and 54% Western Reef Egrets in spring and autumn respectively, while Khor Dubai held only 2 and ] % of the total population. In winter 43% of the Grey Herons counted (not calculated) in the UAE was staging in Khor Dubai, while this area held only l.5% of Western Reef Egn::ts. In Khor al Beidah no Western Reef Egrets were counted at all in winter (although some do occur then), while 46% of the total wintering population was counted in Abu al Abyadh.
43 Waterbird studies
Evans (1994) estimated the total non-breeding population in western Asia for Grey Herons to be 10,000 birds, which means that at least 7% may be present in the UAE in autumn and 2% in spring. The total non-breeding population of Western Reef Egrets in West and Southwest Asia is estimated 17,000 individuals; this would mean that at a single moment in autumn 22% and in spring 6% may be present. However, Aspinall (1996a) estimated the UAE breeding population to be between 300 and 1000 pairs, which means that the calculated population in autumn may in fact have consisted entirely of UAE breeding birds with their young.
Numbers of other waterbirds
The UAE holds between 15-33% of the world population of the Socotra Connorant endemic to the Arabian Gulf, so this country holds a large responsibility for the protection of this species. Alas, the fishennen as well as other people don't like "black seabirds" (this includes Sooty Gulls) and during the last two or three decades already six out of fifteen colonies have become extinct.
It is interesting to note that numbers of Flamingos increased after the municipal sewage plant started discharging treated effluent into Khor Dubai in the early 1970's (Platt 1994). Platt (1994) suggested that the Flamingos benefited from the large numbers of benthic worms, especially ragwonns Nereidae, which are feeding on detritus and may have increased during this time. As Broad-billed Sandpipers also specialize on ragwonns, this may well have been the cause for the rise in numbers during the 1970's and 1980's, culminating in the peak counts of 4050 during 1986 (Uttley et al. 1988).
The UAE's coast bordering the Indian Ocean holds the country's largest numbers of migrating and wintering terns and Sooty Gulls. Traditional fisheries, in which small fish are landed on the beach, are probably vital to migrating and resting birds. The world's breeding range of Sooty Gulls is restricted to the Arabian Gulf and the Red Sea (apart from a tiny colony at the East African coast). Within the UAE this species breeds only in two colonies in the Arabian Gulf; this part of the population is estimated at 235 pairs (Aspinall 1996a). In Oman approximately 11,000 pairs are breeding (Evans 1994). The flock of 3000 Sooty Gulls observcd on 18 May at the beach north of Khor Kalba represents up to 7% of the world's population (cl Evans 1994, Lewington 1996). There are apparently only very few other sites holding comparably large numbers and all are found in Oman.
From all arcas in the UAE Khor Dubai still holds the highest numbers ofwadcrs and a high density of waterbird specics in general. The remark made by Utl1cy et al. (1988) that "Khor Dubai is very well protected at present" however is not true any more: the area is threatened by construction (albeit in the surrowlding), and from pollution and disturbance.
44 Waders and other waterbirds in the United Arab Emirates
6.2 VISIBLE MIGRATION OF WADERS Guido Keijl
Methods
Information on departure of waders was gathered by both systematic and incidental observations. Systematic observations at Khor Dubai were carried out from the "new police post" at the northwestern side of the creek, from late afternoon until dusk (Figure 4.2). Most waders appeared to leave the area in a northwesterly direction and were thus best observed on this side of the lagoon. Departing waders were defined as single birds or flocks leaving the area, (usually) calling intensely and quickly ascending to great altitude (c! Piersma et al. 1990). Disappearing birds were followed with binoculars until out of sight. On several occasions waders did not actually leave but returned and landed somewhere on the mudflats. These birds are included in the departing flocks: it turned out that they in fact did want to leave, as several flocks left later after an aborted attempt. In the results only the time and number of actual leave was used. Information was gathered on species composition, time of departure, flock size, whether or not birds vocalized, and direction of departure, measured with a compass. Time of sunset was noted as well. It must be noted that waders leaving the area in a northeastern, eastern or southeastern direction may have been missed, due to the size of the area, wind force and wind direction, and loudness of the calls of some of the waders (notably Little Stint, Dunlin, Curlew Sandpiper and Lesser Sandplover). To compare our findings, and to enlarge the sample sizes, data on wader departures along the Arabian Gulf coast of Saudi Arabi a (between 17 April and 21 May 1991; data of G.O. Keijl) are incorporated here as well (see Figure 6.8 for location of the study area along the Saudi coast). The data of migrating waders in Saudi Arabia have also been partly published elsewhere (Evans & Keijl 1993a, b).
Results
A total of 1194 waders belonging to 13 species (out of 25 seen in Khor Dubai) left, or attempted to leave, Khor Dubai on 8 April and between 28 April and 7 May. Of these 13 species Temminck's Stint was the only species not recorded during any of the counts. Out of the 39 migrating flocks, two appeared to arrive, while of the 37 flocks seen leaving nine returned (but some left afterwards; Table 6.7). Observations on departure were made during a period of a few days only, so we cannot speculate on seasonal variation in departure. To enlarge samples on migrating waders, data collected along the Gulf coast of Saudi Arabia during April-May 1991 are used here as well. There, 90 flocks were seen departing, comprising 1226 individual birds.
The species seen leaving in largest numbers were Little Stint and Curlew Sandpiper. During the days of the strongest departure (in the UAE: 29 April - 2 May for Curlew Sandpiper and 2-4 May for Little Stint) the biggest drop in numbers was noted during the
45 Waterbird studies regular wader counts (Figure 6.4). This was also the case for Lesser Sandplover, Broad-billed Sandpiper, Dunlin and Bar-tailed Godwit.
Behaviour United Arab Emirates It could usually be predicted which birds were going to depart. These birds were usually standing closer together than other birds at that particular time and either not doing anything, preening, or calling agitatedly, while other birds where either actively foraging or sleeping. Suddenly the birds would fly up, rising steeply, immediately flying into the direction of their intended heading, calling intensely. Several flocks left but returned after a while. Some flocks flew up but immediately returned, while others seemed to depart and could be followed for hundreds of metres and up to several minutes before they returned. Returning birds were often singing while they were landing again (established in Little Stint, Broad-billed Sandpiper, Curlew Sandpiper, Greenshank and Bar-tailed Godwit). Some birds also sang during departure, while birds in all flocks were very vocal. Exception was a single Ringed Plover, which called only once or twice but in fact left silent. Almost all waders left in monotypic flocks. Exceptions were associations of six Greenshanks and one Reeve, and three Greenshanks and one Ringed Plover. Several Curlew Sandpipers and Little Stints left simultaneously, but formed monotypic flocks during or soon after gaining height, possibly because Curlew Sandpipers proceed faster than Little Stints. Possibly the departure of one flock instigated other flocks to leave at the same time. The six Greenshanks and single Reeve arrived from the south or southeast when they were first noted, and landed, calling agitatedly, near other waders at a roost. The Reeve landed some tens of metres away from the Greenshanks but immediately took off when the Greenshanks attempted to leave and joined the flock. The flock came back and landed, the Reeve again at some distance, but when the Greenshanks left shortly after, the Reeve joined again and left together with the Greenshanks.
Table 6.7 Waders leaving, or attempting to leave, Khor Dubai on 8 April and between 29 April and 7 May 1995. The number of flocks and the total number of birds involved are given. % = percentage of birds leaving relative to the total number of all wader species present during the previous count.
flocks total % number 8 April 1 110 4 29 April 2 145 5 30 April 4 248 8 I May 3 89 3 2 May 9 186 6 4 May 13 219 10 7 May 6 197 10
Flock size Flock size did not differ between the UAE and Saudi Arabia for large nor for small species (Mann-Whitney U-test, p> 0.1), thus the data could be considered one database. Most flocks consisted of 2-50 birds (Figure 6.5; data for the UAE and Saudi Arabia combined). Average flock size for large waders (12; see figure 6.5) was smaller than for small waders (23; Student's Hest, t = 2.797, p< 0.01, df= 127; Table 6.8). The largest flocks however were formed by Bar-tailed Godwits, while Temminck's Stints and Ringed Plovers were seen
46 Waders and other waterbirds in the United Arab Emirates migrating in very small flocks. This could be due to a combination of small sample size, the sub-optimal place for these species or the "'Tong time of year for maximum migratin. Flock size also differed between small species. Of the two species seen leaving most commonly, Little Stint and Curlew Sandpiper, flock size was significantly smaller in thc former than in the latter (data for UAE and Saudi Arabia combined; Student's t-test: t = 3.80, p< 0.01, df= 44). Flock size was on average 1.3 times smaller than flock size experienced by the individual birds. This is exactly the same figure which was calculated for wader flocks departing from the Banc d'Arguin (Piersma et al. 1990b) and from northwestern Australia (Tulp et al. 1994).
Figure 6.5 Flock size of waders (number of individuals) departing from Khor Dubai and Saudi Arabia (G. Keijl own data). The upper part of the bars present the large species (Grey Plover, Pacific Golden Plover, Redshank, Greenshank, Ruff, Bar-tailed Godwit, Curlew, Collared Pratincole) the lower part the small species (all other species). The number of flocks is given above the bars.
47 Waterbird studies
Table 6.8 Average flock size (± standard deviation, SO) and number of flocks (n) of waders departing from Khor Oubai, UAE, in spring 1995 and Saudi Arabia in spring 1991. Species are ranked according to (average) flock size. Only species of which more than one flock was observed are included. • indicates species which were only observed emigrating in Saudi Arabia, .. indicates species only observed emigrating in the UAE.
calculated SO n average
Curlew 2.0 1.3 8 Temminck's Stint .. 2.5 0.7 2 Ringed Plover .. 2.7 1.5 3 Terek Sandpiper 3.8 1.5 4 Collared Pratincole • 4.0 2.2 9 Greenshank .. 4.5 2.1 2 Wood Sandpiper . 5.2 5.0 5 Tumstone S.S 5.3 6 Ruff 8.7 9.8 7 Redshank' 12.8 9.0 5 Broad-billed Sandpiper 15.0 7.1 9 Little Stint 17.3 11.1 23 Lesser Sandplover 17.3 16.3 4 Curlew Sandpiper 42.0 28.4 23 Grey Plover 42.3 46.7 3 Ounlin 32.2 41.8 6 Bar-tailed Godwit 47.3 30.1 4
Daily timing In the UAE most birds left about one hour before high tide (Figure 6.6), but this might be a result of the few observation dates, on which high tide fcll just before sunset (high tide on 2 May 16.16 hrs, sunset 18.50 hrs local time). There appeared to be a stronger relation between departure time and sunset, with 62% of the birds and 66% of the flocks leaving within 30 minutes around sunset (Figure 6.7). A few waders left after dusk (Little Stint twice, Curlew Sandpipcr and Broad-billed Sandpiper both once); departing flocks could be heard but not seen any morc because of the darkness. Therefore, it is well possible that more birds departed but were out of hearing distance. Apparently the high tide may instigate departure during the late afternoon, but it is the low sun on which the waders orientate (c! Piersma et al. 1990a, Tu1p et al. 1994).
Direction United Arab Emirates Out of 28 flocks actually leaving, 15 departed in a northwesterly direction. This would bring them to the Gulf-coast of Saudi Arabia, or to the Black Sea if they continued their flight (Figure 6.8). A few waders left in other - sometimes unexpected - directions: onc flock of 40 Lesser Sandplovers left towards the southwest (possibly to the Emirates Golf Course), one flock of 58 Pacific Golden Plovers left towards the west, and three flocks of Terek Sandpipers flew east (of these latter "flocks" one consisted of three individuals; the other two were only heard, but consisted of at least two individuals). During all observations there was a fairly strong wind (W 4-5), which could have deviated birds from their usual course. Waders departing from the Banc d'Arguin, Mauritania, did not
48 Waders and other waterbirds in the United Arab Emirates
% 25 10 6 7 7 3 2
20
15
10
5
0 -6 -5 -4 -3 -2 -1 0 2 3 4 5 6 time to high tide (hrs)
Figure 6.6 Percentage of wader flocks departing from Khor Dubai relative to high tide, spring 1995. The number of flocks is given above the bars. normally compensate for wind drift, except when (on one occasion) tail wind was experienced (Piersma et al. 1990b). A few flocks in Mauritania which were initially departing in deviating directions choose another (final?) direction after a few minutes, hence probably reorientated.
Saudi Arabia Numbers of departing Little Stints from the Jubaillagoons, Saudi Arabia, were probably underestimated, since the observation distance to closely observe emigration was too large for this species. Small numbers of Lesser Sandplover, Dunlin, Broad-billed Sandpiper and Curlew Sandpiper may have been missed for the same reason. The strongest migration was noted between 10 and 21 May. Most waders departed towards the north or north-northeast (81 %, n = 87; Figure 6.8), which would bring them to the Caspian Sea or in the direction of the Taimyr peninsula. Most waders left with headwinds (76%, n = 67), or with little or no wind (51 % with wind force 0-1 Beaufort, 75% with wind force 0-2, n = 78). Exceptions occurred on five dates, when the wind force was 5 Beaufort. The strong tail- or side wind apparently did not make the waders choose a different departure direction (Table 6.9). On 16 May, with a strung tail wind (ESE 5), a maximum of nine flocks was seen leaving, involving 97 individuals of six species. Recently, Butler et al. (1997) suggested that not only for large long-distance migrants but also for small short-distance migrant waders wind assistance is a prerequisite to reach their destination in good condition. It may be a coincidence that half of the flocks of Broad-billed Sandpiper and Tumstone seen leaving left with strong wind; in other waders the majority left under calm conditions.
49 Waterbird studies
2 2 2 3 3 11
30
20
10
o -150 -130 -11 0 -90 -70 -50 -30 -10 10 30 time to f sunset (min) sunset
Figure 6.7 Percentage of wader flocks departing from Khor Dubai relative to sunset, spring 1995. The number of flocks is given above the bars.
Seasonal timing Van def Have et al. (1988) and Piersma et al. (1990b) showed that a species will depart later from its wintering area when it breeds further north. As it is very likely that most waders wintering in or migrating through the Arabian Gulf have a more easterly destination than those wintering in West-Africa, the mid-point of breeding latitude was estimated again (from Cramp & Simmons 1983 and Hayman et al. 1986), considering that most species would breed (at least) east of the Kola Peninsula (except Broad-billed Sandpiper). Therefore, mid-points of breeding latitude in Table 6.1 0 deviate (slightly) from those presented by Piersma et al. (1990b) for all species. For several species we found slightly later departure dates than Piersma et al. (1990b). This is partly due to the lack of observations before the beginning of May in the UAE, as can be deduced by comparing the median departure dates (Table:> 6.10, 6.11, Figure 6.9) and the counting data of Khor Dubai (see 7.2.1).
50 Waders and other waterbirds in the United Arab Emirates
N t
Figure 6.8 Total number of waders and number of flocks, indicated with figures, departing from Saudi Arabia in spring 1991 (G Keijl own data) and from Khor Dubai, DAE, in spring 1995. In the figure from Saudi Arabia, black bars indicate the prevailing wind direction during observations on departure. In Khor Dubai the wind was always westerly during the observations.
May 20
10
April 30
20 @ (j)
10
20 30 40 50 60 70
Figure 6.9 Median departure date of waders in Khor Dubai, DAE, (spring 1995) and Saudi Arabia (spring 199 I) against mid-point of breeding latitude ("NB). The regression line (least square method) is calculated through 20 points (circles only); r2 = 0.36, t = 3.19, p< 0.01. The equation of the line y = 0.57x + 3442,12 is significant (t = 3.189, df = 18). I=Lesser Sandplover, 2=Collared Pratincolc, 3=Avocet, 4=Black-winged Stilt, 5=Little Ringed Plover, 6=Redshank, 7=Black-tailed Godwit, 8=Marsh Sandpiper, 9=Curlew, 10= Greenshank, II=Terek Sandpiper, 12=Wood Sandpiper, 13=Broad-billed Sandpiper, l4=Ringed Plover, 15=Temminck's Stint, 16=Bar-tailed Godwit, 17=Ruff, 18=Pacific Golden Plover, 19=Grcy Plover 20=Little Stint, 21=Dunlin, 22=Sanderling, 23=Curlew Sandpiper, 24=Turnstone.
51 Waterbird studies
Table 6.9 Wader flocks leaving with strong wind (:d Beaufort) from the lubail lagoons, Saudi Arabia, spring 1991. It is indicated whether or not the birds were deviating from the dominating course taken by flocks of conspecifics on days with less wind (n).
date wind species flight deviating n direction
10/4 SS Collared Pratincole N no 9 13/4 NW5 Collared Pratincole N no 9
2/5 NNE5 Broad-billed Sandpiper N no 6 16/5 SSE 5 Broad-billed Sandpiper N no 6 19/5 NNE5 Broad-billed Sandpiper N no 6
16/5 SSE 5 Little Stint N no 16 16/5 SSE 5 Little Stint NNE no 16 16/5 SSE 5 Little Stint NNW yes 16
16/5 SSE 5 Curlew Sandpiper NNE no 12
16/5 SSE 5 Lesser Sandplover NNW yes 3
16/5 SSE 5 Tumstone N no 6 16/5 SSE 5 Tumstone NW yes 6 19/5 NNE5 Turnstone NNE no 6
16/5 SSE 5 Avocet NW
Table 6.10 Median departure dates from waders in the Arabian Gulf compared to departure dates in West-Africa (latter taken from Piersma et al. 1990b). Waders are ranked south to north according to mid-point of breeding latitude (in ON; estimated from Cramp & Simmons 1983 and JIayman et al. 1986). For estimation of breeding latitude for species also breeding east from the Western Palearctic it is assumed that they originate from east of the Kola Peninsula. Numbers of birds concern Arabian Gulf only. species West-Africa Arabian number of number of mid-point of Gulf waders flocks breeding latitude Avocet 14/4 16/5 1 40 Redshank 10/4 21 /4 64 5 50 Curlew 2113 28/4 16 8 55 Greenshank 22/4 3/5 9 3 60 Ringed Plover 27/4 4/5 8 3 68 Bar-tailed Godwit 25/4 30/4 190 4 70 Dunlin 29/4 17/5 193 6 73 Grey Plover 29/4 7/5 127 3 70 Tumstone 30/4 18/5 33 6 75 Sandcrling 9/5 6/5 8 75
52 Waders and other waterbirds in the United Arab Emirates
Piersma et al. (1990a) found a departure delay of 2.3 days per degree, which was roughly similar to other biological data gathered in the arctic (see Piersma et al. 1990a, p. 127 for references). We calculated a departure delay of only 0.6 day per degree. There could be several reasons for this difference:
• lack of data before 6 April; • the relationship between breeding latitude and departure date is not linear at all, but rather curvilinear, because arrival in the arctic must be protracted (like the breeding season itself) for more southerly breeding waders • the difference in climatic conditions between western and northern Europe, where the sea has a large influence on the climate, while the continental climate of Central Asia makes food for waders at stop-over sites probably become available only much later in the season; • the fact that birds departing from West-Africa make a longer stop-over in the West European staging sites, while it is possible that the sites along the Black Sea and Caspian Sea are not yet suitable for waders by the beginning of April due to climatic circumstances. This could mean that birds using the East-AfricanlWest-Asian Flyway have to make a non stop flight from the Arabian Gulf to the breeding areas.
Dunlin wintering in West-Africa originate from Iceland and Northwest-Europe (Pienkowski & Dick 1975, Wymenga et al. 1990) and start breeding relatively early in the season. The more easterly breeding Dunlins are all high arctic breeders and therefore leave much later. The rather late departure date for Lesser Sandplovers (Table 6.11) can be explained by the fact that this (sub)species breeds high up in the mountains, where climatic circumstances such as temperature and snow cover, are comparable to the high arctic.
Table 6.11 Median departure dates from waders in the Arabian Gulf (not counted/present in West-Africa; see also Table 6.10). For estimation of mid-point of breeding latitude (in ON) of Lesser Sandplover only the breeding range of C. m. pamirensis/atrijrons was considered.
species Arabian number of number of mid-point of Gulf waders flocks breeding latitude Lesser Sandplover 18/5 69 4 30 Collared Pratincole 29/4 35 9 40 Black-winged Stilt 20/5 2 I 45 Little Ringed Plover 17/4 4 1 50 Black-tailed Godwit 8/5 I I 50 Marsh Sandpiper 23/4 15 1 55 Wood Sandpiper 14/5 26 5 60 Terek Sandpiper 4/5 15 4 60 Broad-billed Sandpiper 13/5 120 8 66 Ruff . 14/5 58 7 70 Temminck's Stint 2/5 5 2 70 Pacific Golden Plover 30/4 58 73 Little Stint 13/5 397 23 73 Curlew Sandpiper 7/5 966 23 75
53 Walerbird studies
6.3 BIOMETRY Guido Keijl
Methods
Waders were caught using mistnets, which were erected on the mudflats on the southeast side of the mudflats, south of the police post, on 11 and 12 April and daily between 27 April and 3 May. Five sections of three to eight two-shelf or four-shelf nets of 12, 15 and 20 metres were put on the main roost, before or between the mangrove plantations or close to the pipeline at the south side of the creek. Catching was done during late evening or at night just before and during high tide. The nets were opened approximately three to four hours before high tide. Near the central nets, which were closest to the main roost of Broad-billed Sandpipers and other waders, song of Broad-billed Sandpiper was played on a cassette recorder. The nets were checked when the water was just entering the area of the main roost, since it was observed that after this moment there was little movement of waders. After processing the birds the nets were closed, usually during high tide, when sometimes a few more waders were caught. The birds were ringed with incoloy rings, supplied by the National Avian Research Centre, and sexed and aged, as far as possible, following Prater et al. (1977). Ages are given following the EURlNG-codes (4 = older than first calendar year,S = second calendar year and 6 = older than second calendar year). Measurements included wing, bill, tarsus, and weight. After weighing the birds were released on the spot. Weights were corrected for the time lag between catching and weighing, using the formula W1 W = ----'----- o I _ (f1t * 0.795) 100 in which Wo = corrected weight, W\ = measured weight, ~t = time between catching and weighing, 0.795 = percentage of weight loss per hour (calculated from Broad-billed Sandpipers in the Sivash, Ukraine; G. Keijl and P. Ruiters unpubl.). Moult score was noted according Ginn & Melville (1983). Chicks of Kentish Plovers were caught opportunistically by hand during the day and released after ringing.
Results
A total of 74 full grown waders were captured with mist nets (Appendix 8). Only data for Kentish Plover, Lesser Sandplover and Curlew Sandpiper are summarized below; other waders were captured in small numbers. Waders and other waterbirds in the United Arab Emirates
Kentish Plover
Apart from 19 pulli, eight adults were captured (Table 6.12). One bird could not be sexed (still in winter plumage on 12 April). From the other birds, one female and three males were in their second calendar year.
Table 6.12 Measurements (in mm) and weight (in g) of Kentish Plovers captured in April and May 1994 in Khor Dubai, United Arab Emirates. The data are also given separately for males and females. avg = average, sd = standard deviation.
sex wing bill tarsus weight
all avg 106.5 15.5 27.6 35.8 sd 2.78 1.04 1.76 3.73 n 8 8 8 8 range 103-111 14.3-17.2 25.8-30.3 31-41
d'd' avg 106.3 15.4 27.1 33.5 sd 2.63 1.27 2.13 2.29 n 4 4 4 4 range 104-110 14.3-17.2 25.8-30.3 31-35.5
\1\1 avg 106.8 15.5 28.0 37.4 sd 3.30 0.94 1.49 3.94 n 4 4 4 4 range 103-111 14.4-16.7 26.0-29.6 32.5-41
Lengths of bill and tarsus of Kentish Plovers (sexes combined) captured at Merawah in autumn (Figure 4.1 in Skakuj & Stawarczyk 1997), 225 km wouthwest of Khor Dubai, matched exactly those captured by us. Wings of Kentish Plovers measured at Merawah were a trifle longer (107.8 mm) as a result of freshly moulted primaries. Kentish Plovers captured in Khor Dubai in October 1987 had longer wings (average d'd' 111.8, n = 14, \1 \1 109.4, n = 18; DSP 1987). Also Etheridge (1971) found longer wings in Kentish Plovers captured in the emirate of Sharjah in winter (sexes combined, average 108, n = 12). Aspinall (1996a) noted that local breeding Kentish Plovers are slightly smaller than winter visitors as well, but the results from the different studies are ambiguous. In Saudi Arabia, Kentish Plovers were captured between 17 April and 21 May 1991 in a lagoon system near Jubail. These all belonged to the local breeding population, since most captured birds had breeding patches and chicks were observed as well. These birds had significantly longer wings than the Kentish Plovers caught in the United Arab Emirates (males: average wing = 111.4, sd = 2.44, n = 14, range 108-115; Student's t-test, t = 3.63, df= 16, p< 0.01; females: average wing = 110.3, sd = 2.91, n = 24, range 104-115; t = 2.19, df= 26, p< 0.05; O. Keijl unpubl.), but were otherwise similar in measurements.
55 Waterbird studies
Lesser Sandplover
In the Lesser Sandplover five subspecies are recognized (Cramp & Simmon 1993). Based on summer plumage characters, birds occurring in the Arabian Gulf probably mainly belong to the subspecies C. m. pamirensis, but a few atrifrons may occur as well, as some males had a completely black forehead. Of the captured Lesser Sandplovers one adult bird could not be sexed because it was still in winter plumage (11 April). Another bird still in winter plumage on 28 April was a second year bird. The other birds were (almost) in full summer plumage (all plumage code 7, only one female had plumage code 6) and could be sexed on the colour of the mask. Males were on average slightly smaller in wing length than females (Table 6.13; Student's t-test, t = 2.23, df = 8, p< 0.05). The birds were larger in wing and bill dimensions than measurements given in Cramp & Simmons (1983).
Table 6.13 Measurements (in mm) and weight (in g) of Lesser Sandplovers captured in April and May 1994 in Khor Dubai, United Arab Emirates. The data are also given separately for males and females . avg = average, sd = standard deviation.
sex wing bill tarsus weight
all avg 132.4 17.6 33.3 79.8 sd 3.75 0.72 0.79 12.5 n 12 12 12 12 range 126-140 16.2-18.7 31.8-34.6 56-93
d'd' avg 130.8 17.7 33.4 80.3 sd 2.22 0.52 0.78 8.02 n 4 4 4 4 range 129-134 17.3-18.4 32.6-34.4 69-88
'f'f avg 134.7 17.4 32.9 87.2 sd 3.39 0.89 0.62 4.66 n 6 6 6 6 range 131-140 16.2-18.7 31.8-33.6 80.5-93
The average departure weight (the shaded area in Figure 6.1 0, estimated from the largest drop in numbers, Figure 6.4) was 82 g, which is 19% higher than the weight on 11-12 April. A regression of weight against date indicates a weight increase of 0.8 gram per day (r2 = 0.23, t = 1.70, df= 10, p> 0.05).
Lesser Sandplovers caught on Merawah in autumn were similar in measurements to birds caught by us (sexes combined; Skakuj & Stawarczyk 1997). Only wings of birds caught at Khor Dubai were slightly longer (132.4 compared to 129.2). The Lesser Sandplovers captured in autumn and winter were considerably lighter (respectively 54.4 g, range 41-63, adults, sexes combined; Skakuj & Stawarczyk 1997 and 59 g, range 51-68 g; the emirate of Sharjah, Etheridge 1971).
56 Waders and other waterbirds in the United Arab Emirates
Figure 6.10 Body weight increase of Curlew Sandpipers and Lesser Sandplovers caught in Khor Dubai in April-May 1995. The shaded areas represent the period when most birds left the area (Figure 6.4 and paragraph 6.2.2). The lines represent the average weight increase.
57 Waterbird studies
weight (g) 95,_------,------~~ 90 • • • 85 • • 80 • •• • • 75 • 70 • 65 • 60 • departure 55 ~--,__,--~--_.~~--~--_.~~ 15 20 25 30 5 10 15 April May
Figure 6.11 Body weight increase of Lesser Sandplovers in Saudi Arabia, spring 1991 (G. Keijl own data). The line represents the average weight increase.
In Saudi Arabia Lesser Sandplovers were captured between 21 April and 20 May 1991. Adult birds (>2 cy, n = 32) were similar in measurements to the birds captured in Khor Dubai. Females in Saudi Arabia were signific:mtly lighter (average 78.0 g, sd = 7.53, n = 16, Student's t-test, t = 2.67, df= 20, p< 0.02), even if heavily oiled birds were excluded from the sample (see Evans & Keijl 1993a for details). Average departure weight was 77.2 g. A regression of weight against date of Lesser Sandplovers caught in Saudi Arabia indicates a lower weight increase (0.33 g per day, Figure 6.11; r> = 0.018, t = 0.80, df= 35, p> 0.05) than of Lesser Sandplovers in the UAE (Figure 6.10). The lower weight increase and departure weight were probably influenced by the oil pollution and smoke conditions in Saudi Arabia in 1991 (Evans & Keijl 1993b).
.'IS Waders and other waterbirds in the United Arab Emirates
Curlew Sandpiper
Out of 35 birds captured, 27 could be sexed on summer plumage characters (c! Cramp & Simmons 1983). Females were virtually similar in measurements to males, except for bill length (Table 6.14, Student's t-test, p< 0.01).
6.12 Measurements (in mm) and weight (in g) of Curlew Sandpipers captured in April and May 1995 in Khor Dubai, United Arab Emirates. The data are also given separately for males and females. avg = average, sd = standard deviation.
sex wing bill tarsus weight
all avg 134.1 38.5 31.3 70.3 sd 2.39 2.77 1.26 7.85 n 35 35 35 35 range 128-139 33.5-43.9 29.3-33.9 54-85.0
d'd' avg 134.3 36.7 30.9 71.9 sd 2.36 2.38 1.57 8.37 n 13 13 13 13 range 131-139 33.5-42.5 29.3-33.9 54-85
'i''i' avg 133.6 40.3 31.8 71.8 sd 2.53 2.25 0.93 6.56 n 14 14 14 14 range 128-137 36.8-43.9 29.8-33.0 61-83
Both sexes were similar in measurements to Curlew Sandpipers caught in Tunisia in spring 1990 (Wellinga 1993), with the exception of the males, having significantly longer bills than the Tunisian birds (which were sexed on basis of discriminant analysis; Student's t test, t = 2.04, df = 90, p< 0.05). This could be because one bird in the UAE, sexed as male, had a bill length of 42.4. If this bird is excluded the difference is not significant. The measurements however are comparable to Curlew Sandpipers caught in South Africa, where (internally sexed) males with very long bills (range 32-42 mm) were also present (Elliott et al. 1976). Measurements were similar to adults captured in autumn at Merawah (Abu Dhabi; Skakuj & Stawarczyk 1997). The average departure weight (the shaded area in Figure 6.10, estimated from the largest drop in numbers; Figure 6.4 and paragraph 7.2.2) was calculated to be 73 g (range, estimated from the figure, 61-85 g), comparable to those in South Africa (79-80 g) and Britain (75 g; Elliott et al. 1976). Average departure weight was 30% higher than the weight of birds captured on 11-12 April. A regression of weight against date indicates a weight increase of 0.9 gram per day (r2 = 0.52, t = 6.03, df = 33, p< 0.01). This is exactly what Barter (1986) found for Curlew Sandpipers in Australia, while Elliott et al. (1976) found a weight increase of 0.6 g per day for Curlew Sandpipers in South Africa (both in March).
59 Waterbird studies
60 Waders and other waterbirds in the United Arab Emirates
6.4 FEEDING OBSERVATIONS Paul Ruiters, Guido Keijl, Tom van der Have & Eric Marteijn
Methods
Detailed observations on prey intake were made for Broad-billed Sandpipers, Grey Plovers, Pacific Golden Plovers and Lesser Sandplovers. For these species, as well as for a few other species, feeding intensity (percentage of birds foraging) was established by scanning the mudflats during the low-water period and noting whether birds were feeding or not.
Prey species Methodology on sampling of macrozoobenthic animals is given in chapter S. Additional samples of cj Tylonereis spec. were taken in order to describe the correlation between worm length and biomass. Worm length was measured in two ways: 1) with the worm in relaxed position, and 2) with the worm in stretched position. The latter measurement was used to calculate actual worm length for worms taken by plovers (assuming that when a worm was caught by a plover and length was estimated, it was also stretched).
Feeding of Broad-billed Sandpipers Food protocols of Broad-billed Sandpipers were made on nine days between 13 April and 6 May. During a protocol session a single feeding individual was followed as long as possible (range 24 seconds to 21 minutes). Captured worms were estimated relative to bill length (with an average bill length of 30 mm; G. Keijl & P. Ruiters unpubl.). Droppings were collected on the mudflats on 19 and 20 April, on a site where Broad billed Sandpipers were feeding, after observations were made. Only droppings which were certainly produced by Broad-billed Sandpipers were collected. Unfortunately, the droppings were lost in the laboratory and therefore calculations concerning energy intake could not be made.
Feeding of plovers On 3, 4 and 5 May Lesser Sandplovers, Grey Plovers and Pacific Golden Plovers were closely observed while feeding on ragworms. An attempt was made to follow a comparable sample of birds of each species on different times during the low tide, in order to estimate the total intake per tidal cycle. Data per species were total observation time, number of ragworms captured, fate of the ragworm (eaten or rejected), and length of the worm measured in "leg-lengths" of the predator (giving a maximum worm length; see Figure 6.13). Total leg length was measured on museum specimens in The Netherlands, from the distal end of the tarsometatarsus to the point where the tibia enters the body (Table 6.15); the rounded figure was used for the calculations. On 5 and 6 May droppings of Lesser Sandplovers, Grey Plovers, Pacific Golden Plovers and Curlew Sandpipers were collected on the high tide roost to measure jaw lengths of ragworms consumed. As the birds roosted in loose flocks more or less separately from each other it was rather easy to collect droppings per species. Droppings of Grey Plover were easily recognized by their large size, while those of Curlew Sandpiper were smallest. Droppings of the other two species were more similar in size, while the largest of Pacific Golden Plovers could possibly have been mixed up with those of Grey Plover. These species
61 Waterbird studies seldom roosted together though, and if doubt arose over a particular dropping it was not collected. At least ten droppings were collected from each species.
Table 6.15 Leg lengths (in mm) of Grey Plover, Pacific Golden Plover and Lesser Sandplover (measured on skins), used for estimating lengths ofragworms.
Grey Plover Pacific Golden Plover Lesser Sand plover average 87.6 82.6 59.9 standard deviation 6.5 4.8 4.9 n 9 20 14 range 75-93.5 74.5-91.5 51-69
Calculations of energy intake For plovers lengths of eaten worms were estimated in two different ways: during field observations by comparison of worm length with leg length and by measuring jaw lengths found in faeces. Jaw lengths of ragworms Tylonereis spec. are a good estimator for body length (e.g. Zwarts & Esselink 1989). The allometric relations to relate maximum worm lengths from jaw lengths and to convert estimated worm lengths to biomass are given in chapter 5.3 and Figure 5.4. The net energy intake rate (NEI) was calculated by multiplying the intake rate (mg/sec), with the caloric value of the prey (21.69 kJ/g; Pienkowski et al. 1984) and with the assimilation efficiency (0.78; Kersten & Piersma 1984). For calculations of daily energy intake (DEI) it is assumed that intake rate during the night was similar to that during the day (c! Zwarts et al. 1990a, Turpie & Hockey 1993, McNeil & Rodriguez 1996). Khor Dubai is fairly bright even at night because of the surrounding highway-lights, and during catching activities we could see and hear birds still active on the mudflats then. The daily energy intake (DEI) was calculated by multiplying the NEI with the length of the foraging period and the average fraction of the time the birds were actually foraging. The costs of living in the tropics (thermostatic costs and activity costs) are estimated at only a factor of 1.8 times the basal metabolic rate (BMR; Zwarts et al. 1990a, Klaassen et al. 1990). With this value the daily energy expenditure (DEE) was established. It is assumed that the energetic costs for making one gram of body tissue (fat: protein ratio of 7 : 3; Lindstrom & Piersma 1993) is 34.3 kJ (Kersten & Piersma 1987). Estimated intake rates were compared to predicted intake rates (gross food intake, GFI, as a function of body mass), using the formula: GFI = 47.6 M0723 (GFT in g AFDM.day·l; M in kg; Zwarts et al. 1990b) for waders in tropical areas.
Results
Observations on the feeding habits of birds in Khor Dubai focused on Broad-billed Sandpiper, Curlew Sandpiper, Grey Plover, Pacific Golden Plover and Lesser Sandplover. All waders were foraging most of the time during the low water period (Table 6.16, Figure 6.12). The larger species, notably Pacific Golden Plover, but !lQ1 Grey Plover, spent less time fccding than the smaller species, while Little Stint and Broad-billed Sandpiper were
62 Waders and other waterbirds in the United Arab Emirates feeding for longest, which is in accordance with findings of Zwarts et al. (1990), who also found that large waders spend less time feeding. Terek Sandpipers also spend less time feeding, like the larger waders. This can perhaps be explained by the fact that their diet (crabs) forces them to take time for digestion (c! Zwarts & Dirksen 1990).
% foraging 100 .. . . . 80 . 60 40 20 Curlew Sandpiper Lesser Sandplover
-6 -4 -2 HW 2 4 6 -6 -4 -2 HW 2 4 6
100 . . 80 60 40
20 Pacific Golden Plover Grey Plover
-6 -4 -2 HW 2 4 6 -6 -4 -2 HW 2 4 6
100 .. 80 60 40 20 Terek Sandpiper Broad-billed Sandpiper
-6 -4 -2 HW 2 4 6 -6 -4 -2 HW 2 4 6
time relative to high tide (hr)
Figure 6.12 Foraging activity of six wader species in Khor Dubai during daytime relative to high tide (HW). Each dot indicates the perccntage of foraging birds in a flock.
63 Waterbird studies
% 2.5,--,------,------, Broad-billed Sandpiper 2 ~ 1.5 (\J e1 #. LO 0.5 -.:i 0'> o unknown 30,------Lesser Sand plover
18
30 Grey Plover 25 20 15 10 5 o 16.5 19.8 worm length (cm)
Figure 6.13a Maximum wonn length consumed, estimated during observations of foraging birds.
66 Waders and other waterbirds in the United Arab Emirates
% 40 ,------, Curlew Sandpiper 30
20
10
0 ~1~0--~1~1--~1~2--~13~~ 40.------Lesser 30 Sandplover
20
10
O ~c'-::-- 40,------, Pacific Golden Plover 30
20
10
o"-----c""::-----:"-:--' ~"- 19 20 21 40 .------, Grey Plover 30
20
10
19 20 21 worm length (cm)
Figure 6.13b Maximum worm length consumed, calculated from jaw lengths measured in faeces.
67 Waterbird studies within a second. Occasionally, a captured wonn was pulled out but subsequently refused and left behind on the mud. We could find no obvious reason for the birds to refuse a wonn, but it may be that a small number of wonns holds parasites detrimental to birds, as was previously established for bivalves and Oystercatchers (c! Hulscher 1982). Total observation for Grey Plovers was 2 hours, 58 minutes and 45 seconds, for Pacific Golden Plovers for 2 hours, 4 minutes and 42 seconds and for Lesser Sandplovers 2 hours, 13 minutes and 51 seconds. All three species were taking the largest wonns available (Table 6.18, Figure 6.13 and Chapter 5). For Curlew Sandpiper no length estimations for captured wonns were made in the field, because they swallowed their prey too quickly. The wonns eaten by the different species are not statistically different in length (Student's t-test, p> 0.1 for all groups). The wonns as calculated from jaw lengths found in droppings are much larger than the wonns estimated in the field for Grey Plover, Pacific Golden Plover and Lesser Sandplover (Table 6.18 and Figure 6.13). The data show that all birds select the largest wonns and ignore the smaller ones.
Table 6.18 Average wonn lengths (cm) as estimated in the field and calculated from jaw lengths found in faeces (see text). For calculating maximum wonn length from jaw length
the fonnula Lwo"" = 10.277 * LJ•wO 786345 was used (r2 = 0.S35).
Grey Plover Pacific Golden Lesser Curlew Plover Sandplover Sandpiper FIELD average 6.9 6.7 5.8 sd 5.69 4.88 4.27 n 141 79 IS1 range 1.7-19.8 1.6-18.6 1.1-18.0
FAECES average 16.2 15.4 16.2 16.9 sd 1.11 1.30 I.S2 I.S4 n 147 109 48 22 range 12.6-16.2 12.1-18.1 10.9-18.6 14.1-19.6
68 Waders and other waterbirds in the United Arab Emirates
Table 6.19 Intake of Grey Plover, Pacific Golden Plover and Lesser Sandplover in the United Arab Emirates, 3-5 May 1994. Given are average number of prey per minute, net energy intake (NEI; in Watt) and daily energy intake (DEI; in kJ), as calculated from the field observations and from faecal analysis. For Grey Plover a BMR of 1.84 W was used, assuming a body weight of 250 g, based on Grey Plovers captured in April-May 1990 in Tunisia; Ruiters 1993). For Pacific Golden Plover a BMR of 1.29 W was used, assuming a body weight of 153 g (Johnston & McFarlane 1967). For Lesser Sandplover a BMR of 0.81 W was used, assuming a body weight of 80 g; this study).
prey/minute NE! DEI field dro~~ings field dro~~ings
Grey Plover average 0.75 6.71 9.93 297 437 sd 0.70 range 0.10-3.40 n 19
Pacific Golden Plover average 0.56 4.01 7.17 156 279 sd 0.41 range 0.0-1.61 n 15
Lesser Sandplover average 1.16 8.74 16.73 384 736 sd 0.81 range 0.16-3 .25 n 21
Table 6.20 Net energy intake rate (Watt) of four wader species in Khor Dubai, United Arab Emirates, spring 1995, estimated on basis of field observations and droppings, compared to predicted gross food intake (GFI). For calculation of the predicted intake rate the formula GFI = 47.6>1< M 0.729 was used (M = body mass in kg) (Zwarts et al. 1990a).
found: predicted: field droppings Grey Plover 6.7 9.9 6.7 Pacific Golden Plover 3.7 7.2 5.2 Lesser Sandplover 8.0 16.7 2.9 Broad-billed Sandpiper 1.2 1.8
69 Waterbird studies
The results of the field observations give other data for intake rate than for the droppings (Table 6.19): the difference is a factor 1.5 for Grey Plover (the difference in worm lengths captured and actually eaten is a factor 2.3), 1.8 (2.2) for Pacific Golden Plover and 1.9 (2.8) for Lesser Sandplover. One explanation for the difference between faeces and field observations could be that the smallest jaws are fully digested and therefore not present in the faeces any more. This would lead to an overestimation of intake rate. However, this has not been described in literature. An alternative explanation is that all birds do feed on the largest worms available, but that in a number of cases the (back part of the) worms break and only a small part is taken, which in the field would be scored as a smaller prey. This leads to an overestimation of intake rate as well. For Grey Plovers the daily energy intake (Table 6.19) calculated from the field observations is slightly lower compared to the 328 kJ for Grey Plovers in the Dutch Wadden Sea in autumn (Kersten & Piersma 1987). Intake calculated from the droppings is much higher and comparable to that found for Grey Plovers in South Africa (416 kJ, Turpie & Hockey 1993).
For Pacific Golden Plovers the DEI is 156 kJ (field obs.) or 279 kJ (droppings) (Table 6.19). This would give a surplus daily energy of -44 and 79 kJ respectively, and a weight increase of -1.3 and 2.3 g per day. DEI for Lesser Sandplovers is 384 (field obs.) or 736 kJ (droppings), resulting in a surplus daily energy of 258 (610) kJ. This gives a weight increase of 7.5 or 17.8 g per day respectively. Departure weight of Lesser Sandplovers in Australia is estimated to be 84 g (Tulp et al. 1994). If we estimate lean weight to be 50 g (the lightest - heavily oiled - but apparently fit Lesser Sandplovers captured in Saudi Arabia in spring 1991 weighed 52 g; G. Keijl own data), departure weight to be 80 g and flight speed 65 kmIh, they have a calculated flight range of 3000 km (according to the formula of Davidson 1984). With a departure weight of 90 g (heaviest bird captured in Saudi Arabia in spring 1991 weighed 91 g) the flight range estimate is 3927 km. The distance between Khor Dubai and the mid-point of breeding latitude is 3384 km along the great cirele route.
Discussion
The shallow western part of Khor Dubai is the most important wader area in the UAE: it holds a remarkably high number for such a small site. The area is enriched by sewage, while a salt gradient as a result of effluent water from the desalination plant creates a range of "micro habitats" when the highly saline waters mingles with seawater. Thus, food is available in abundance and this, together with the fact that hunting is prohibited, enables birds to stay in high densities. The plantation of small mangrovc trecs has probably enlarged living possibilities for benthic animals (by creating new micro-habitat), but also diminished the foraging surface available to wadcrs and other birds, and possibly changed part of the nature of the mudflat as well: our data show that large polychacte worms (i.e. Nereidae) are not found in the vicinity of the mangrove trees. Food consumption for the 15 most numerous waders in Khor Dubai is relatively high (Table 6.21) and virtually the same as found for Langebaan lagoon in South Afiica (el Zwarts 1988). It should be noted however that comparison with numbers presented in Zwarts (1988)
70 Waders and other waterbirds in the United Arab Emirates should be considered with care, since the calculation for Khor Dubai was made with the equation presented in Zwarts et al. (1990a).
Table 6.21 Weights, wader density and predation pressure (in g per hectare per day) of the most common wader species (making up 95% of the total number of waders) in Khor Dubai in spring 1995 and autumn 1994. Food intake was estimated using the formula of gross food intake from Zwarts et al. (1990a; see also methods). Weights were taken from Cramp & Simmons (1983), except for Oystercatcher (Spiekman 1993a), Grey Plover (Ruiters 1993), Dunlin (Spiekman 1993 b), Redshank (Van Roomen 1993), Greenshank (Stegeman 1993), Tumstone (De Goeij 1993), and for Kentish Plover, Lesser Sandplover, Little Stint, Curlew Sandpiper, Bar-tailed Godwit and Terek Sandpiper (this study). For autumn all weights were taken from Cramp & Simmons (1983).
SPRING AUTUMN weight Nlha g/ha/day weight Nlha g/ha/day Oystercatcher 459 0.19 5 548 0.58 18 Ringed Plover 63 0.27 2 60 0.55 3 Kentish Plover 36 1.33 6 46 3.55 18 Lesser Sandplover 80 6.41 48 70 0.24 2 Grey Plover 250 2.22 39 217 1.14 18 Sanderling 83 0.11 I 50 0.04 0 Little Stint 28 1.90 7 23 1.0 I 3 Curlew Sandpiper 70 4.91 34 53 \.12 6 Dunlin 58 0.21 1 52 8.63 48 Bar-tailed Godwit 269 1.95 36 345 1.26 28 Curlew 990 0.03 I 800 0.21 8 Redshank 145 0.03 0 112 0.98 9 Greenshank 208 0.02 0 174 0.12 2 Terek Sandpiper 73 0.53 4 60 0.05 0 Tumstone 130 0.15 2 109 O.ll
Total 185 164
For all areas the percentage of species feeding on crabs, bivalves, (large) worms and other prey (for instance, small worms and small crustaceans) is calculated (Figure 6.14a-b). For several species food items were studied or taken from Cramp & Simmons (1983) (Table 6.22). For a few species eating more than one food item but seen in very small numbers (e.g. Black-tailed Godwit, Common Sandpiper) only one food item was assumed. In species eating more than one food item the number was divided accordingly (e.g. Oystercatcher, eating both worms and bivalves in the UAE).
71 Waterbird studies
Table 6.22 Food of waders in wetlands in the UAE.
prey insects ostracods small large amphipods small large bivalves small worms worms crabs crabs fish Oystercatcher X X Ringed Plover X Kentish Plover X X Lesser Sandplover X Pacific Golden Plover X Grey Plover X Sanderling X X Little Stint X X X Curlew Sandpiper X X X Dunlin X X X Broad-billed Sandpiper X X Bar-tailed Godwit X Curlew X X Whimbrel X X Redshank X X X X Greenshank X X X Terek Sandpiper X Tumstone X X X X
Khor Dubai is characterized by high numbers of waders, especially species feeding on worms. This area has the softest mud and relatively small areas with dry sandy patches mainly along the edges (Figure 5.1). Especially in spring, most areas held waders feeding predominantly on worms (Figure 6.14, Table 6.23). The percentage of waders feeding on worms is high compared to other areas in the Arabian Gulf or "nearby" Oman. Waders feeding on bivalves were found mainly along the west coast in spring, but also along the northern coast in autumn. Inland areas and the east coast held virtually no waders feeding on bivalves but many birds feeding on "other" food items. The high number of birds which feed on crabs found in the inland Al Ghar area and the Golf Course in autumn is caused by the number of Kentish Plovers, which were, of course, not feeding on crabs in these areas, because there are no crabs in these areas. Proportions of waders feeding on a specific food item did not deviate much from those found in other intertidal areas along the East Atlantic and Mediterranean Flyway (c! Kersten et al. 1983, Zwarts 1988, Keijl et al. 1992, Spiekman et al. 1993). The results from the macrozoobenthos sampling show that very high densities of polychaete worms are present in Khor Dubai (Table 5.3). What is not shown in this table is that even though this area ranks second lowest in Nereidae, it does hold large individuals, which are especially attractive to plovers. Other areas holding large numbers of (small) worms like lebel Dhanna - where Broad-billed Sandpipers were seen feeding on small worms in autumn - are apparently less appealing. The areas in the west of the U AE held more waders feeding on bivalves, while the highest density of bivalves was found along the coast north of Abu Dhabi. This shows more clearly in the distribution of birds in autumn than in spring.
72 Waders and other waterbirds in the United Arab Emirates
Table 6.23 Percentages of wader species feeding on crabs, bivalves, large worms and other food in tidal areas in the UAE compared to areas elsewhere. See Figure 6.14 for further explanation. Data for Oman (BaIT al Hikman) are from Green et al. (1992), data from Saudi Arabia from Evans & Keijl (l993b).
food choice UAE KhorDubai Oman Saudi Arabia spring spring autumn autumn winter spring crabs 8 6 9 11 5 14 bivalves 8 23 22 23 5 worms 74 80 50 52 61 60 other 10 13 18 15 12 21
It is believed that waders will look for areas with the highest density of their preferred prey, but species feeding on crabs are probably an exception to this rule. The distribution of crab-eating waders is not concurrent with the highest densities of crabs measured: apart from Khor Kalba, which held the highest density of (large) crabs (which are only eaten by Curlews and Whimbrels), Khor Dubai and Al Jazirat were richer in crabs than the other areas. Probably, waders feeding on crabs are not limited by the availability (absolute numbers) of their prey, but rather by the density of other waders in general. It was observed that crab eating species (like Terek Sandpipers) "tried to avoid" conspecifics during foraging: when two Terek Sandpipers approached each other they changed direction. This can be understood when it is realized that crabs have excellent eyes and can see a bird (or human being) approaching from a distance of several metres, after which they dash to their burrows. Birds feeding on crabs in high densities are disturbing each other because they disturb the crabs and will therefore have great difficulty in catching any prey at all.
73 Waterbird studies
Khor al Beidah ~ ~~ \ Bel Ghelam
\\
Ad Dab'iyyah
AI Ghar -'------~--
o crabs • bivalves E'J worms • other
Figure 6.14a Percentage of waders feeding on crabs, bivalves, wonns and other food items, per area in spring. Areas with very small numbers are left out. For this figure we assumed the next species feeding on the following food items: crabs - Dromas ardeola, Charadrius alexandrinus, Numenius phaeopus, N. arquata, Xenus cinereus; bivalves - llaematopus ostralegus, Calidris alpina, Calidris spec., Tringa lolanus; wonns - Haematopus ustralegus, Charadrius hiaticula, C. mongolus, C. leschenaultii, Pluvialis fulva, P. squatarola, Calidris alba, C. ferruginea, c. alpina, Calidris spec" Limicolafalcinellus, Limosa lapponica, Numenius arquata; other - Cursorius cursor, Himantopus himantopus, Glareola pratincola, Charadius dubius, C. alexandrinus, Vanellus indicus, V. leucurus, Calidris minuta, C. temminckii, Philomachus pugnax, Limosa limosa, Gallinugo gullinago, G. stenura, Tringa nebularia, T. glareola, 7: stagnatilis, Ac/iti,\' hypo/euco!>, Arenaria interpres, Phalaropus loha/w'. 74 Waders and other waterbirds in the United Arab Emirates
Khor al iif fira
Shaksa'eet al Ya'en Khor Dubai \ 8 G ~ Jebel Dhanna Abu al Abyadh e U
\- '= \
Ad Dab'iyyah
D crabs • bivalves L.Jworms I!i other
Figure 6.14h Percentage of waders feeding on crabs, bivalves, worms and other food items, per area in autumn.
75 Waterbird studies
6.5 BREEDING OF KENTISH PLOVERS AT KHOR DUBAI Guido Keij I & Eric Marteijn
Kentish Plovers are common in the United Arab Emirates and breed along the entire coast as well as at some inland sites. The country's population is estimated at 1000-3000 pairs. In Khor Dubai 150-200 pairs are breeding (Aspinall 1996a). As the country holds a responsibility for this species in the Middle East (1 % of the estimated breeding population for Africa/Southwest Asia is 80 pairs, while I % of the non-breeding population is set at 250 individuals; Evans (1994), Aspinall (I 996a) designated the Kentish Plover a priority species. During spring 1995 three or four nests were located opportunistically between the halophyte vegetation surrounding the creek, but these were not visited. The first newly hatched chicks were seen on 28 April; on this and the next day 19 pulli were ringed. After hatching, both parents accompanied the chicks, which started feeding along the edge of the bare mudflats.
Although Kentish Plovers are still numerous at Khor Dubai and in the UAE, the population at Khor Dubai is at risk for a number of reasons, most of which are related to the vegetation: the salt-tolerant vegetation (vegetated sabkha) is characteristic for such a coastal habitat (Boer & Warnken 1996). In a natural situation this vegetation is flooded every once in a while during spring tides and storms. Because the vegetation around most of the creek is not inundated any more because it is locked off by the dike, it is possible (but not known) that it will eventually die off; the edges of the area used to be flooded regularly, thus creating a specific (micro)flora and (micro)fauna, the latter forming a potential food source for Kentish Plover chicks. Because of a change in water supply it is possible that the natural system has been destroyed and has had, or will have, a negative influence on potential prey species available to wader chicks; even though the shallow southern half of the area is designated a nature reserve, the mudflats themselves do not form a closed system and are in close relation with the vegetated part behind the dike. Kentish Plovers are breeding between the low bushes but take their young to the mudflats 10 feed. The dike forms a barrier between the breeding and feeding areas. It is possible, although not known to us, that the parents with their chicks take shelter at night between the bushes, and crossing the dike twice a day (or even more frequently) makes them vulnerable to predation; although mangrove trees may provide shade for waders during the hottest part of the day, they have reduced the mudflat surface available to waders for feeding. Mangrove trees usually grow in a muddy substrate, while Kentish Plovers forage on a more sandy substrate. Because a different microhabitat develops around the trees and the area becomes more muddy, it is likely the suitable feeding habitat for Kentish Plovers will be reduced; because the vegetation can be considered a permanent pioneer stage, it is susceptible to disturbance and changes (c! B6er & Warnken 1996). As there are cars driving criss-cross through the area, tracks are made everywhere and the vegetation will not regenerate on these tracks, as can be seen all around the creek. This small-scale desertification makes the area unsuitable for breeding Kentish Plovers; cars may destroy nests by simply riding over them;
76 Waders and other waterbirds in the United Arab Emirates
dogs may destroy nests and disturb the breeding birds. They no doubt also predate the chicks; grazing cattle (sheep, goats) may trample nests and disturb breeding birds; even if the creek itself is well protected, building around the area in the near future will greatly diminish it because of inereased tourism, pollution and disturbance.
Summarizing the above, it can be concluded that the developments in Khor Dubai (building of dikes, mangrove planting, intense use of the vegetated saltflats around the creek) have had, or will have, a negative influence of its wildlife, among which are breeding Kentish Plovers.
The following important conservation measures to protect breeding Kentish Plovers are proposed: the dike surrounding the creek should be (partly) broken down again, thus connecting the vegetated sabkha behind the dike with the tidal area again; the area should be made accessible by one or two roads only, which do not have a dead end but enter on one side and leave on another side. Other presently usable roads should be blocked off; there should be stricter rules for entering the area from the main road surrounding the creek, for instance by signs and road blocks. The dike enclosing the water and mudflats should be accessible during (part of) the day only; it should be made impossible to enter the vegetated parts with (four-wheel drive) vehicles or motor cycles from the main road, as well as from the dust roads through the area itself. This can be easily achieved by digging steep ditches along the road, or with large stones or other blocks along the dirt tracks; herding of sheep/goats should be forbidden, preferably throughout the year, but especially during the breeding season.
See chapter 8 for other, general, recommendations for conservation measures.
77 Spring migration ofBroad-billed Sandpipers in Khor Dubai
7. SPRING MIGRATION OF BROAD-BILLED SANDPIPERS IN KHOR DUBAI
Tom van der Have
Introduction
In this chapter the spring migration pattern of Broad-billed Sandpiper is reviewed from literature. The migration pattern in Khor Dubai is discussed. The main question: is Khor Dubai a major stop-over site in the Arabian Gulf in spring?
Literature data on spring migration of the Fenno-Scandian breeding population
January-March The wintering areas of the Broad-billed Sandpiper are concentrated around the Arabian Gulf and along the Arabian Sea (Glutz van Blotzheim et al. 1975, Cramp & Simmons 1983, Evans 1994, Van Gils & Wiersma 1996). Some 300-6000 may winter along the Saudi Arabian coast (Zwarts et al. 1991), 1500-2000 in Bahrain (Hirschfeld 1994), <1000 in Khor Dubai, UAE (Richardson 1997) and an estimated 5000 in Barr al Hikman (Green et al. 1992, 1994; 1600 counted, but 5000 extrapolated from large numbers of unidentified calidrids). Unknown numbers winter in Pakistan and in the Red Sea. Departure period from Barr al Hikman is unknown. Spring passage in Bahrain peaks in the last decade of March, and only small numbers are observed after April (Hirsehfeld 1994).
March-May Few spring stop-over sites are known between the wintering areas in the eastern part of the Arabian Gulf and the Mediterranean. Tarut Bay is one of the few sites suitable for Broad billed Sandpipers, as they select the muddiest parts of the intertidal mudflats (Zwarts et al. 1991, Evans & Keijl 1993a). Peak numbers occurred in the last week of April and first week of May (Table 1), and departure occurred between 2-16 May 1991 (Evans & KeijI1993a).
May-June The dates of peak migration in the East-Mediterranean are within a surprisingly short period: between 14 and 20 May (Table I). Birds staging in Egypt and Israel may originate from wintering areas in the Red Sea. Broad-billed Sandpipers were present in Egypt from March onwards (Geene et al. 1994). Most birds stopping over in Turkey and Bulgaria are probably from the Arabian Gulf-area. In southern Turkey birds arrived in late April and probably stopped over for long periods. In Central and northern Turkey, Broad-billed Sandpipers were present for a very short period with stop-over periods of about one day (Hustings 1994, Schekkerman & Van Roomcn 1993). Compared with the mid-latitude of breeding range, ::;pring migration in the (:ukurova delta~ was relatively late and similar to Red neeked Phalarope (Van der Have et al. 1988). In the most important stop-over site, Sivash lagoon::;, Ukraine, peak numbers were present between 17-23 May 1993, and departure occurred between 27-30 May 1993 (Table 7.1). The next stop-over sites are probably situated close to the breeding areas in the Baltie Sea and the Gulf of Bothnia. Near Oulu, Finhmd, peak migration occurs in the last week of May and first days of hme (Table 1, Karjalahti & Ala-Vaino 1988). Birds arrive on the
78 Waders and other waterbirds in the United Arab Emirates breeding grounds between 1 and 15 June (Cramp & Simmons 1983), while by that time most other wader species in the same habitats have already started nesting. In spring, very few birds are observed west of the line Lake Manzala - Danube Delta - Oulu. Very few birds are observed during spring between the Baltic and northern Black Sea.
Table 7.1 Dates of peak spring migration of Broad-billed Sandpipers in the West-Palaearctic.
locality country date of peak migration n reference
Arabian Gulf coast (1990-92) Bahrain 20-31 March 1-200 Hirschfeld 1994 Tarut Bay Saudi Arabia 25 April-7 May 1991 ? Evans & Keijl1993a departure 2- I 6 May 1991 Evans & Keijl 1993a
Eastern Mediterranean Lake Manzala Egypt 20 May 1990 80 Geene et al. 1994 Ma'agan Mikha'el Israel 14 May 1989 8 Keij I et al. 1992 (:ukurova deltas east Turkey 14 May 1987 57 Van der Have et al. 1988 (:ukurova deltas west Turkey 15 May 1990 69 Kivit et al. 1994 Pal as Golii Turkey 15 May 1989 41 Schekkerman & Van Roomen 1993 KlZlhrmak Delta Turkey 19 May 1992 73 Hustings 1993 Black Sea coast Bulgaria 13-28 May 6 Uhlig 1984
Northern Black Sea Eastern Sivash Ukraine 17-23 May 1993 2000 Keijl & Ruiters in prep. departure 27-30 May 1993 Keijl & Ruiters in prep.
Baltic Sea Oulu (1977-82) Finland 28 May-2 June 144 Karjalahti & Ala-Vaino 1988
Was Khor Dubai used as spring staging site by Broad-billed Sandpipers?
Field work in Khor Dubai in spring 1995 started 7 April. If Khor Dubai was used as a stop-over site by the birds wintering in Oman, then our counts might have started just one or two weeks too late. From counts in Bahrain it was clear that migration in the eastern part of the Arabian Gulf may peak in the last week of March (Hirschfeld 1994). Numbers during the first two counts of Khor Dubai, 11 and 18 April showed that only small numbers were present (maximum of 60), compared to about several hundreds in mid-winter (S. Aspinall & C. Richardson in litt.). More than one thousand never have been observed here after 1986 Cc. Richardson pers. comm., this report). Numbers decreased rapidly to just over ten birds by the cnd of April (paragraph 6.2.1). The four Broad-billed Sandpipers captured in Khor Dubai wcrc second calendar year birds, suggesting that most of the birds present might have been in their second calendar year. Only regular weekly counts between October and May can reveal the real importance of Khor Dubai as a spring staging site for Broad-billed Sandpipers. The available data from Tarut Bay, Saudi Arabia, suggest that Broad-billed Sandpipers stop-over in the northwestern part of the Arabian Gulf (Evans & Keijl 1993a).
79 Spring migration of Broad-billed Sandpipers in Khor Dubai
Here they possibly acquire the energy stores needed for the relatively long migration lap to the Sivash, Crimea, a distance of about 2600 kilometres. The nearest suitable wetlands in between are the coastal lagoons in southern and northern Turkey (Table I). From our studies and others (e.g. Zwarts et al. 1991), only wetlands with soft mud flats may be suitable for Broad-billed Sandpipers. Along the Saudi Arabian coast they are only locally common. Along the Iranian coast only three wetlands may qualify as suitable spring stop-over sites for Broad billed Sandpipers: Hilleh (29 °10' N 50°50' E) and Monde (28°10' N 51 °18' E) River Deltas (42,600 ha and 46,700 ha, respectively), and Bushire Bay (27,900 ha, 29°00' N 50°53' E) (Evans 1994). No detailed wader counts are available of these wetlands yet.
Spring migration pattern of Broad-billed Sandpiper: a proposal
Spring migration of Broad-billed Sandpipers could be as follows. Departure from the wintering areas (Oman, eastern Arabian Gulf) takes place in March-April. Before arriving on the breeding grounds in Fenno-Scandia in the first half of June, three or four major stops are made in: a northwestern Arabian Gulf; b eastern Mediterranean, particularly Turkey; c northern Black Sea coast, particularly the Sivash lagoons, Crimea; d Baltic coast of Finland.
Stop-avers at a and c are probably long (>10 days), at band d possibly short «10 days). If a bird departs from its wintering site on 1 March and arrives at its breeding area on 1 June it may have spent about 88 days at stop-over sites and less than four days in flight. (The distance between the Arabian Gulf and the breeding grounds is approximately 4400 km; estimated flight speed is 60 km/h.) The late migration schedule could be either related to the dependence on prey availability at major stop-over sites or late suitability of the breeding habitat.
80 Waders and other waterbirds in the United Arab Emirates
8 CONCLUSIONS AND RECOMMENDATIONS Guido Keij I & Tom van der Have
Conclusions
Khor Dubai Wildlife Sanctuary • The density of waders in Khor Dubai Wildlife Sanctuary is 21 birds per hectare in spring and in autumn, and 60 birds per hectare in winter; the latter figure is higher than found anywhere else in the world.
• Khor Dubai Wildlife Sanctuary is of international importance because of the regular presence of many wader species, including Fenno-Scandian Broad-billed Sandpipers, in autumn, winter and spring.
• Khor Dubai Wildlife Sanctuary is a unique wetland within the United Arab Emirates due to the combination of the availability of high densities of invertebrates (notably large ragworms), waders and Flamingos, and the situation close to Dubai city.
• Khor Dubai Wildlife Sanctuary is especially important for Grey Herons during autumn, winter and spring.
• The mangroves, especially in Khor Dubai Wildlife Sanctuary, contain high densities of snails which are not eaten by birds.
• The mangrove plantations in Khor Dubai Wildlife Sanctuary have diminished the feeding areas of waders and Flamingos significantly and reduced ragworm populations.
• The sabkha and salt marsh surrounding the mudflats of Khor Dubai Wildlife Sanctuary are important as a roosting site for waders and a breeding area for Kentish Plovers.
• For some wader species Khor Dubai Wildlife Sanctuary is one of the last stopover sites before the breeding grounds and is vital as a refuelling area.
• Waders, notably breeding Kentish Plovers, and other waterbirds are regularly being disturbed by cars and helicopters, even though the area is a nature reserve, because there are too many possibilities to enter.
• Very few waterbirds occur in the parts of Khor Dubai Wildlife Sanctuary with deep water.
• Very few waders make use of the mangroves.
Other wetlands • The total number of waders using the UAE coast at a single moment is 91,500 in autumn and 71,100 in spring. Khor Dubai Wildlife Sanctuary holds 5% and 6% of this number respectively on only 0.07% of the total available surface of intertidal area.
81 Conclusions and recommendations
• In spring 61 and in autumn 56 species of waterbirds were counted in 11 wetlands in the UAE.
• In winter 124,222 waterbirds, including 37,5 14 waders, were counted in 32 wetlands.
• Total numbers of 13 wader species regularly occurring in most wetlands in the UAE exceed 1% of the East-African - West-Asian flyway populations.
• Grey Heron and Western Reef Heron are the most numerous heron species in the UAE.
• During migration up to 22% of the flyway population of Western Reef Egrets and up to 7% of Grey Herons occur in the UAE.
• Large numbers of Western Reef Egrets are staging in Khor al Beidah in autumn and spring, while the highest numbers in winter are found in Abu al Abyadh.
• The number of Broad-billed Sandpipers using the UAE as a staging/wintering area has decreased since 1986 for unknown reasons.
• Numbers of Sooty Gulls along the east coast of the UAE represent 7% of the world population.
• Large numbers of migrating and wintering terns and Sooty Gulls are associated with the traditional fishing methods practised along the east coast.
• Khor al Beidah is an important foraging area for the nearby breeding Socotra Cormorants.
• Khor Kalba is in urgent need of protection, not only because of the presence of the endemic White-collared Kingfisher Halcyon chloris kalbaensis, but also because of the (aesthetic value of) the old mangroves, as well as the presence of other unique wildlife.
• The small intertidal area of Khor Kalba is endangered because of the potential danger of oil pollution, because of high numbers of people entering the area on foot and by car for collecting crabs and shells and for leisure activities.
~< ~)
82 Waders and other waterbirds in the United Arab Emirates
Recommendations
Khor Dubai Wildlife Sanctuary
• Khor Dubai Wildlife Sanctuary should be managed by cooperating organisations (or, otherwise, by a single organisation) responsible for all aspects of protection and management (water quality, land use, access, etcetera).
• The protected area should be extended to include the surrounding vegetated zone, since this is used by breeding Kentish Plovers as well as by roosting waders, and would act as a buffer zone.
• The area around Khor Dubai Wildlife Sanctuary should be closed off to cars, to avoid disturbance of resting and breeding birds.
• The current extent of viable mangrove should be considered as an added aesthetic and ecological value to the Khor Dubai Wildlife Sanctuary but should not be extended.
• A management plan for Khor Dubai Wildlife Sanctuary should be developed integrating the use of the area for conservation and recreation.
• It is recommended that numbers of waterbirds are counted monthly and that a more intensive study of the carrying capacity of Khor Dubai Wildlife Sanctuary is carried out, to better understand changes taking place in this area in terms of diminishing numbers of Broad billed Sandpipers and, possibly, other wader species.
• There should be no other waste water being disposed of into Khor Dubai Wildlife Sanctuary.
• Dubai city should extend in a direction other than toward the surroundings of Khor Dubai.
Other wetlands • Richardson et af. (1994) identified fifteen wetlands (including offshore islands) of international importance within the UAE. It is recommended that all coastal sites become wildlife reserves and gain complete protection.
• For a full protection of the intertidal area of all wetlands and to seabird colonies, oil shipping routes should be situated far offshore and away of islands. The east coast north of Khor Kalba, with its important numbers of migrating and wintering terns and gulls (e.}? Dibba Bay and Qurrayah), is also vulnerable for oil pollution and construction works.
• Colony sites of Socotra Cormorants and Sooty Gulls, as well as the birds themselves, should be protected throughout the year.
• Khor Kalba should become a Wildlife Sanctuary with its own restrictions and regulations. The entrance of cars and people should be regulated.
S3 Suggestions for future research
9. SUGGESTIONS FOR FUTURE RESEARCH Tom van der Have & Guido Keijl
The United Arab Emirates
• How important is the Arabian Gulf in spring and autumn for migrating waders and other waterbirds?
• What is the carrying capacity of the coastal wetlands in the Arabian Gulf for waders in autumn, winter and spring? This question should be answered by integrated studies of wader numbers, food choice and macrozoobenthic surveys.
• The extensive mangrove areas in Abu Dhabi are of particular interest for studying carrying capacity for waders.
Broad-billed Sandpipers
• Where does the majority of the Fenno-Scandian (nominate) population of Broad-billed Sandpipers overwinter? Important wintering areas may lie in Arabian Gulf itself, Oman, Yemen or elsewhere in the Red Sea, Oman, South-Iran, West-Pakistan or even further south in India.
• How many Broad-billed Sandpipers arc still using Khor Dubai? This should be studied by establishing turn-over rates.
• What role does Khor Dubai Wildlife Sanctuary still play in the annual life cycle of Broad-billed Sandpipers? It is recommended to continue monitoring numbers of waders (and other waterbirds) in Khor Dubai, especially Broad-billed Sandpipers. Khor Dubai is an excellent place for monitoring studies because of its size and accessibility.
• Where do Broad-billed Sandpipers undertake moult of flight feathers in autumn, and where do they moult into breeding plumage? Surveys of potential moulting sites elsewhere in the Arabian Gulf are highly recommended. Sites with especially high potential are estuaries along the West-Iranian coast (c! Evans 1994).
• Are Broad-billed Sandpipers specialized feeders on ragworms Nereis sp. (c! Stikvoort 1994) during the period August-March?
84 Waders and other waterbirds in the United Arab Emirates
10. AVIFAUNA Tom van der Have
In this chapter an annotated list is given of all bird species observed during field work in the UAE in September-October 1994 and April-May 1995. Most observations were done in Khor Dubai and Ras Ghanada, where the main part of the field work took place. Additional observations were done during wetland counts or stops between the study sites (Table 10.1). Instead of a detailed account of all observations an annotated list is presented to give an impression of the bird species diversity in the UAE. A detailed discussion of the avifauna of the UAE can be found in Richardson (1990) and in Aspinall (I 996a, b). The species are listed according to Voous (1973, 1977a, b). Date and locality are only given of scarce and uncommon species. For rare and vagrant species more details are given. These were submitted to the Emirates Bird Record Committee; only accepted records are included. To clarify the distinction between regular and uncommon species observed during the field work, the status is mentioned according to Richardson (1990), Richardson (1994) and Aspinall (1996a). In case subspecies are mentioned, identification is made in the field on basis of plumage characters or on basis of common knowledge. A few recent taxonomic changes have been followed (for instance for Great Grey Shrike, Isenrnann & Bouchet 1993, Panov 1995, Panow 1996, Lefranc & Worfolk 1997). Most waterbird species are included in the regular counts of Khor Dubai and Ras Ghanada and the surveys of other wetlands (Chapter 6). An overview of all species recorded per day and per site is given in Tables 10.1 and 10.2.
The regular coverage ofKhor Dubai and Ras Ghanada gives a crude impression of the spring migration phenology of certain species (Tables 10.1 and 10.2). Notable, for example, was the short stay of Lesser Grey Shrike arOlmd Ras Ghanada at 26 April, which apparently coincided with the short occurrence of Red-backed Shrike, Spotted Flycatcher and (possible) arrival of Clamorous Reed Warbler (Table 10.1). Most waterbirds were present at Khor Dubai during the whole study period (Chapter 6). Exceptions were Great Cormorant, Great White Egret, Marsh Harrier, Spotted Eagle, Osprey and Black-tailed Godwit, which were present only during the first half of April. These observations clearly reflect the early departure from Khor Dubai.
Little Grebe Tachybaptus ruficollis Local resident and winter visitor.
Black-necked Grebe Podiceps nigricol!is Fairly common winter visitor. On la October 3 at Emirates Golf Course.
Persian Shearwater Puflinus lherminieri Uncommon migrant. On 9 October 5 off Dibba. Two birds on 30 April were feeding close to the beach at Khor Kalba on discarded fish, among 1000 Sooty Gulls and one Sooty Shearwater.
Sooty Shearwater Puffinus griseus Single bird on 30 April at Khor Kalba, feeding on discarded fish, up to 30 meters from beach, constituted the first record for the UAE. The bird could be photographed. One (two) was observed during a short sea-watch off Dibba on 1 May: 1 north and I south, probably the same individual, and possibly same individual as on 30 April near Khor Kalba.
!l5 Avifauna
Flesh-footed Shearwater Puffinus carneipes Vagrant. One off Dibba on 9 October 1994 constituted the first record for the UAE.
Great Cormorant Phalacroc(lrax carbo Winter visitor.
Socotra Cormorant Phalacrocorax nigrogularis Breeding resident. On 5 October 1994 a single flock of approximately 40,000 individuals was counted at Umm al Qaiwain.
Little Bittern Ixobrychus minutus Fairly common passage migrant. One juvenile on 10 October 1994 at Emirates Golf Course, one d' on I May in fodder fields of dairy farm at Dibba, two d'd' and one ~ at the Emirates Golf Course on 10 May.
Night Heron Nycticorax nycticorax Passage migrant, winter visitor. One immature at the Emirates Golf Course on 10 May.
Green-backed Heron Butorides striatus Uncommon resident (200-500 pairs, Aspinal\ 1996a) and locally dispersive.
Squacco Heron Ardeola ralloides Uncommon throughout the year. On 30 September 1994 one juvenile at AI Wathba.
Indian Pond Heron Ardeola grayii Regular winter resident at Khor Kalba. Two on 8 October 1994 at Khor Kalba, two birds there on 30 April.
Cattle Egret Bubulcus ibis Regular winter visitor.
Western Reef Heron Egretta gularis Common migrant and local breeder.
Little Egret Egretta garzetta Common winter visitor and passage migrant.
Great White Egret Egretta alba Regular passage migrant and winter visitor.
Grey Heron Ardea cmerea Common migrant and winter visitor.
Purple HerOD Ardea purpurea Regular migrant.
Spoonbill Platalea leucorodia Localised migrant and winter visitor. Only observed in Khor Dubai and Khor Kalba.
86 Waders and other waterbirds in the United Arab Emirates
Greater Flamingo Phoenicopterus rub er Passage migrant and winter visitor.
Egyptian Goose Alopochen aegyptiacus Two individuals at Ras Ghanada on 10 April
Mallard Anas platyrhynchos Common winter visitor.
Pintail Anas acuta Fairly common migrant and wintcr visitor.
Sboveler Anas clypeata Locally common in winter.
Teal Anas crecca Common from autumn to spring. Only observed in autumn 1994.
Garganey Anas querquedula Common migrant. Only observed in autumn 1994.
Pochard Aythyaferina Local but fairly common in winter. Two cJcJ and 7 ~ ~ at Emirates Golf Course on 10 October 1994.
Black Kite Milvus migrans Regular passage migrant and winter visitor.
Marsh Harrier Circus aeruginosus Common winter visitor in coastal wetlands. One ~ 15 April at Al lazirah Khor.
Pallid Harrier Circus macrourus Fairly regular migrant and local winter visitor.
Montagu's Harrier Circus pygargus Regular migrant and winter visitor.
Sparrowhawk Accipiter nisus Regular winter visitor.
Spotted Eagle Aquila clanga Regular winter visitor. Several birds (up to four different individuals) were regularly observed In Khor Dubai. Last observation on 18 April. They were incidently seen taking Yellow-legged Gulls.
Bonelli's Eagle Hieraaetus fasciatus Scarce breeding resident. On 8 October two adults and one juvenile observed and Dibba dairy farm.
Osprey Pandiorl haliaelus Resident, migrant and winter visitor. Up to two different individuals in Khor Dubai.
87 Avifauna
Lesser Kestrel Falco nl1umanni Regular spring migrant along the western edge of the mountains, scarce in autumn and winter. On 1 May 18 at dairy farm at Dibba.
Kestrel Falco tinnunculus Common passage migrant and winter visitor, localised resident breeder.
Hobby Falco subbuteo Scarce migrant. Single adult 26 September 1994 in Abu Dhabi, juvenile on 30 September 1994 at Al Wathba.
Peregrine Falco peregrinus Regular migrant and winter visitor. One adult !j! at Khor Dubai on 11 April.
Sand Partridge Ammoperdix heyi Locally common resident in the eastern mountain districts.
Grey Francolin Francolinus pondicerianus Common and expanding resident, probably all resulting from introduction.
Quail COlurnix coturnix Regular passage migrant. On 26 September 1994 one was seen perched in a tree about 5 m above ground.
Spotted Crake Porzana porzana Fairly common passage migrant. Single individual on 17 April at the Emirates Golf Course.
Baillon's Crake Porzana pusilla Scarce migrant. One 0' on 17 April at the Emirates Golf Course in small reed bed.
Corncrake Crex crex Scarce and irregular migrant. One on 23 April walking early in the morning on stony hill side at Jebel Dhanna. One on 10 May at the Emirates Golf Course.
Moorhen Gallinula chlorapus Regular migrant and winter visitor, locally resident.
Coot Fulica alra Localised winter visitor to a few freshwater sites. One in the small reservoir of the Ziqt Dam on May.
Oystercatcher Haemalopus ostralegus longipes Regular migrant and winter visitor.
Black-winged Stilt Himanlopus himantopus Fairly common migrant and winter visitor.
Crab Plover Dramas ardeola Localised resident, dispersive in winter.
88 Waders and other waterbirds in the United Arab Emirates
Cream-coloured Courser Cursorius cursor Breeding resident. One on 5 October at Umm al Qaiwain, eight on II October 1994 at Al Wathba.
Collared Pratincole Glareola pratincola Regular migrant in late spring and early autumn.
Little Ringed Plover Charadrius dubius Regular migrant and summer visitor.
Ringed Plover Charadrius hiaticula Fairly common migrant and winter visitor to coastal lagoons.
Kentish Plover Charadrius alexandrinus Common breeding resident and winter visitor.
Lesser Sand Plover Charadrius mangolus Very common migrant and winter visitor.
Greater Sand Plover Charadrius leschenaultii Common migrant, small numbers in summer.
Pacific Golden Plover Pluvialis fulva Regular winter visitor.
Grey Plover Pluvialis squatarola Fairly common migrant and winter visitor.
Red-wattled Lapwing Vanellus indicus Widespread resident, mainly in the north and east.
White-tailed Lapwing Vanellus leucurus Uncommon in autumn, rare in spring. One adult at Emirates Golf Course on 10 October 1994.
Sanderling Calidris alba Regular migrant and winter visitor.
Little Stint Calidris minuta Common migrant and winter visitor.
Temminck's Stint Calidris temminckii Regular migrant and winter visitor.
Curlew Sandpiper Calidris ferruginea Very common migrant, particularly in early autumn; scarce in winter.
Dunlin Calidris a/pina Common late autumn migrant and winter visitor.
Broad-billed Sandpiper Limicolafalcinellus Localised late autumn migrant, less common in winter.
89 Avi[auna
Ruff Philomachus pugnax Fairly common migrant and winter visitor.
Common Snipe Ga/linago gallinago Fairly common migrant and winter visitor.
PintaiJ Snipe Gallinago stenura Scarce and localised winter visitor. On 26 September 1994 one in Bateen Wood, Abu Dhabi, three on 10 October at Emirates Golf Course.
Black-tailed Godwit Limosa limosa Uncommon migrant and winter visitor.
Bar-tailed Godwit Limosa lapponica Very common migrant and winter visitor.
Whim breI Numenius phaeopus Fairly common migrant and winter visitor.
Curlew Numenius arquata Fairly common migrant and winter visitor.
Redshank Tringa totanus Common migrant and winter visitor.
Greenshank Tringa nebularia Common migrant and winter visitor.
Green Sandpiper Tringa ochropus Fairly common migrant and winter visitor.
Wood Sandpiper Tringa glareola Common migrant, irregular in winter.
Terek Sandpiper Xenus cinereus Fairly common migrant and winter visitor.
Common Sandpiper Actitis hypoleucos Common migrant and winter visitor.
Turnstone Arenaria interpres Fairly common migrant.
Red-necked Phalarope Phalaropus lobatus Regu lar migrant, winters in large numbers offshore in the Arabian Sea. Largest single flock of 100- 150 birds were seen off Dibba on I May.
Pomarine Skua Slercnrariu~ pomarinus Regular migrant throughout year along coast of Arabian Sea.
90 Waders and other waterbirds in the United Arab Emirates
Arctic Skua Stercorarius parasiticus Regular migrant throughout year along coast of Arabian Sea.
Sooty Gull Larus hemprichii Resident, breeding on offshore islands. On 30 April 1000 at Khor Kalba on the beach, on 8 May single flock of 3000 between Khor Kalba and Fujcira on the beach.
Great Black-headed Gull Larus ichthyaetus Fairly common migrant and winter visitor.
Black-headed Gull Larus ridibundus Very common winter visitor. One large-sized first summer individual with completely black bill on 7 and 11 May in Khor Dubai.
Sabine's Gull Xema sabini One second-year bird in first summer plumage and heavy moult 8 May at Khor Kalba beach constituted only the second record for the UAE.
Slender-billed Gull Larus genei Fairly common migrant and winter visitor.
Lesser black-backed Gull Lams fuscus Fairly common migrant and winter visitor.
Yellow-legged Gull Larus cachinnans Common migrant and winter visitor.
Gull-billed Tern Gelochelidon ni/o/ica Fairly common non-breeding visitor.
Caspian Tern Sterna caspia Fairly common migrant and winter visitor. Apart from observations in Khor Dubai, one adult on 7 April at Ras Ghanada, one on 16 April at Abu AI Abyadh.
Swift Tern Sterna bergii Breeding on offshore islands; scarce winter visitor.
Lesser Crested Tern Sterna bengalensis Breeding summer visitor on offshore islands, few present in winter. One in second calendar year plumage at Khor Kalba on 8 May.
Sandwich Tern Sterna sandvicensis Fairly common migrant and winter visitor.
Common Tern Sterna hirundo Fairly common migrant. About 6000 birds, mainly in second calendar year plumage, were feeding near the beach, close to fishennen on 30 April at Khor Kalba. One adult roosting at the beach showed characters of the race S. h. /ongipennis (photographed). On 8 May 1000 at Khor Kalba.
91 Avifauna
White-cheeked Tern Sterna repressa Fairly common breeding visitor.
Bridled Tern Sterna anaethetus Pelagic summer breeding visitor. One on 14 April at lebel Ali, several offshore on 30 April at Khor Kalba.
Little Tern Sterna albifrons Spring migrant and non-breeding summer visitor. One observation of single individual at Khor Dubai on 20 April.
Saunder's Little Tern Sterna saundersi Summer breeding visitor.
White-winged Black Tern Chlidonias leucopterus Fairly common autumn migrant, localised in spring.
Whiskered Tern Chlidonias hybridus Fairly common during migration. One adult on 26 September 1994 foraging above fountain at roundabout in Abu Dhabi, six on 8 October 1994 at Dibba dairy farm.
Lesser Noddy Anous tenuirostris Vagrant. First observed at Dibba on 14 September 1994 (two birds, C. Richardson pers. comm.). On 8 October 1994 one off Dibba.
Lichtenstein's Sand grouse Pterocles lichtensteinii Localised resident of mountains and adjacent gravel plains. On I May 10-15 drinking late in the evening at Ziqt Dam.
Chestnut-bellied Sand grouse Pterocles exustus Fairly common resident in sandy areas. On 11 October 1994 single flock ofapproximatdy 550 seen at AI Wathba.
Rock DovelFeral Pigeon Columba livia Common resident.
Collared Dove Slreptopelia decaoclo Common resident.
Turtle Dove Streptopelia turtur Summer breeding visitor and passage migrant.
Palm Dove Streptopelia senegalensis Common resident.
Rose-ringed Parakeet Psillacula krameri Locally common.
Alexandrine Parakeet PsiILacula eupatria Locally breeding resident. Small flocks in Abu Dhahi in September-October 1994.
92 Waders and other waterbirds in the United Arab Emirates
Striated Scops Owl Otus brucei Fairly scarce and localised breeding resident. On 28 September 1994 two seen hunting in spotlights in MushrifPark,Dubai.
Little Owl Athene noctua Common resident.
European Nightjar Caprimulgus europaeus Fairly common migrant. One cl' on 10 October 1994 at Emirates Golf Course, one on 9 April at AI Wathba, one on 10 May at Ras Ghanada.
Swift Apus apus Common spring migrant, but scarce at other times.
Pallid Swift Apus pallidus Common breeding visitor in winter and common migrant from northerly populations in spring and autumn.
White-collared Kingfisher Halcyon chloris Endemic subspecies H. c. kalbaensis, resident at Khor Kalba. A complete survey on 1 May resulted in 82 birds in 44 territories, up to the border with Oman (Aspinall 1996a). Some birds were caught for obtaining blood samples, and photographed.
Kingfisher Alcedo at/his Fairly common winter vIsItor. One on 8 October 1994 at Khor Kalba, one on 27 April at Ras Ghanada, one on 30 April at Khor Kalba.
Little Green Bee-eater Merops orientalis Common resident.
Blue-cheeked Bee-eater Merops persicus Very common in autumn, common spring migrant, breeding in small numbers. Along the road near Khor Kalba 25 on 8 May.
European Bee-eater Merops apiaster Regular migrant, breeding locally. Fairly common in September 1994. One on 10 April and one on 27 April at Ras Ghanada.
European Roller Coracias garrulus Regular migrant.
Indian Roller Coracias benghalensis Common rcsidcnt in north.
Hoopoe Upupa epops Common migrant, breeding locally. One on 27 April at Dubai, one on 10 May at the Emirates Golf Course.
Black-crowned Finch Lark Eremoplerix nigriceps Common breeder in sandy desert, dispersive in winter.
93 Avifauna
Desert Lark Ammomanes deser/i Localised resident of stony desert. One on 23 April at lebel Dhanna, one on 2 May at Ziqt Darn.
Bar-tailed Desert Lark Ammomanes cineturus Until recently known only as vagrant. Four birds were observed in song in sandy desert near lebel Dhanna on 23 April.
Hoopoe Lark Alaemon alaudipes Common resident in desert areas.
Short-toed Lark Calandrella braehydactyla Common migrant, rare in winter.
Oriental Skylark Alauda gulgula Vagrant. Single individual on 26 September 1994 a1 racing track in Abu Dhabi.
Crested Lark Galerida eris/ata Very common resident.
Sand Martin Riparia riparia Common migrant, rare in winter and summer.
Pale Crag Martin Hirundo obsoleta Common resident in hills and mountains.
Swallow Hirundo rus/iea Common migrant.
House Martin Deliehofl urbica Uncommon migrant, mainly in spring. One on 7 October at Khor al Khowair, one on 10 May at the Emirates Golf Course.
Richard's Pipit Anthus richardi Regular migrant and winter visitor.
Blyth's Pipit An/hus godlewskii Vagrant. One on 23 April at AI Wathba at close range (with Tawny and Richard's Pipit nearby).
Tawny Pipit Anthus eampestris Common migrant and winter visitor.
Tree Pipit Anthus trivialis Common migrant, rare in winter.
Red-throated Pipit Ant/IUS cervinus Fairly common migrant in spring and localised winter visitor.
Citrine Wagtail Mo/aeilla eitreola Irregular on migration and in winter. On 27 September 1994 two at East Lagoon in Abu Dhabi.
94 Waders and other waterbirds in the United Arab Emirates
Yellow Wagtail Motacillajlava Common migrant. Two d'd' and one 5j! (M f thunhergi) 10 May at the Emirates Golf Course.
White Wagtail Moracilla alba Common winter visitor.
Forest Wagtail Dendronanthus indicus Vagrant. Single individual (photographed) on 10 October 1994 at Emirates Golf Course.
Red-whiskered Bulbul Pycnonotusjocosus Introduced. Local resident. On 26 September two racing track in Abu Dhabi, on 4 October 10 at Bateen Wood, Abu Dhabi.
White-cheeked Bulbul Pycnonotus leucogenys Locally common in Abu Dhabi and Dubai. Hybrids between this species and Red-vented Bulbul regularly observed.
Yellow-vented Bulbul Pycnonotus xanthopygos Restricted to mountains and adjacent gravel plains and on Abu Dhabi Island.
Red-vented Bulbul Pycnonotus cafer Introduced in Sharjah, Abu Dhabi and Dubai.
Rufous Bush Chat Cercotrichas galactotes Fairly common migrant and summer breeder. A few in autumn 1994, one on 9 April at AI Wathba, one on 9 May at Ras Ghanada.
Nightingale Luscinia megarhynchos Fairly common migrant. Several seen in autumn 1994. One on 14 April at lebel Ali, one on 10 May at the Emirates Golf Course. All individuals showed characters of L. m. hajizi.
Robin Erithacus rubecula Very scarce winter visitor. On 4 October 1994 onc at Bateen Wood, Abu Dhabi.
White-throated Robin Irania gutturalis Regular but scarce spring migrant, rare in autumn.
Redstart Phoenicurus phoenicurus Common migrant in spring, rare in autumn.
Whinchat Saxicola rubetra Uncommon migrant. Onc d' on 9 April at AI Wathba.
Isabelline Wheatear Oenanlhe isabellina Common migrant and winter visitor.
Northern Wheatear Oenanthe oenanthe Fairly common spring mi6rrant, scarce in autumn and rare winter visitor.
95 Avifauna
Desert Wheatear Oenanthe deserti Common winter visitor, fairly scarcc on migration. Single bird on I October 1994 at Dabi'yyah.
Pied Wheatear Oenanthe pleschanka Common spring migrant and regular in autumn.
Red-tailed Wheatear Oenanthe xanthoprymna Fairly common in winter, rather scarce in spring. Single bird on 3 October 1994 at Jebel Dhanna.
Hooded Wheatear Oenanthe monacha Scarce migrant and winter visitor, localised breeder. One on 23 April near lebel Dhanna.
Hume's Wheatear Oenanthe alboniger Fairly common resident in the mountains.
Rock Thrush Monticola saxatilis Common spring, rare autumn migrant. One c! in song on 8 May in Hajar Mountains.
Graceful Warbler Prinia gracilis Common resident outside desert.
Scrub Warbler Scolocerca inquiela Localised resident in mountains. Two (also singing) near Massif on 8 October, one on 2 May at Ziqt Dam.
Savi's Warbler Locustella luscinioides Uncommon in spring, scarcer in autumn. On 28 September 1994 one seen well at Zabeel water plant, Dubai.
Sedge Warbler Acrocephalus schoenobaenus Fairly common migrant.
Marsh Warbler Acrocephalus paluslris Common late spring migrant, absent in autumn. On 10 May 50 at the Emirates Golf Course.
Clamorous Reed Warbler Acrocephalus slentoreus Fairly common breeder, some are resident in mangroves, others are dispersive and migratory. On 26- 27 April at Ras Ghanada apparent arrival in mangroves, several singing.
Olivaceous Warbler Hippolais pallida Common breeding bird, fairly common migrant and scarce winter visitor
Booted Warbler Hippolais ,:aligata Fairly scarce spring migrant, rare in autumn. Several singing birds on 30 April and on 8 May in Khor Kalba mangroves. One bird caught and photographed on 30 April.
Upcher's Warbler Hippolais languida Locally common migrant. One on 4 October at Bateen Wood, Abu Dhabi, one on 15 April at AI lazirah. Single bird singing in Hajar Mountains on 8 May.
96 Waders and other waterbirds in the United Arab Emirates
Menetries' Warbler Sylvia mystacea Common spring migrant, scarce in autumn and winter. Four on 26 September 1994 in Abu Dhabi. One rJ' on 14 April at Ras Ghanada, one !j1 on 10 May at the Emirates Golf Course.
Desert Warbler SylvlG nana Common on passage and in winter in desert areas.
Barred Warbler Sylvia nisoria Regular late spring migrant, rare in autumn. One on 14 April at lebel Ali.
Lesser Whitethroat Sylvia curruca minula Common migrant and winter visitor. Only observed in autumn 1994.
Lesser Whitethroat Sylvia curruca blythii Common passage migrant, rare in winter.
Common Whitethroat Sylvia communis Common spring and scarce autumn migrant.
Blackcap Sylvia atricapilla Irregular migrant in autumn and spring.
Willow warbler Phylloscopus trochilus Fairly common migrant, mainly late spring.
Spotted Flycatcher Muscicapa striata Common late spring and early autumn migrant. Four on 26-27 April at Ras Ghanada.
Arabian Babbler Turdoides squamiceps Resident in desert with low bushes. Several at known localities: AI lazirah and Khor Kalba.
Purple Sun bird Nectarinia asiatica Common to very common resident.
Golden Oriole Griolus oriolus Regular spring and autumn migrant. One on 24 September at AI Wathba, one on 8 May at the Emirates Golf Course.
Isabelline Shrike Lanius isabellinus Common migrant and winter visitor.
Red-backed Shrike Lanius collurio Common late spring migrant, uncommon in autumn. One on 26 April at Ras Ghanada.
Lesser Grey Shrike Laniu~ minor Scarce migrant, mainly in spring. A small influx of at least ten birds on 26 April around Ras Ghanada. One on 6 May at Khor al Beidah.
Great Grey Shrike Lanius meridfonalis aucheri Common resident in north, scarcer in south and west.
97 Avi[auna
Steppe Grey Shrike Lanius pallidirostris Regular passage migrant and winter visitor.
Masked Shrike Lanius nubicus Common migrant in early spring and autumn. One juvenile on 4 October near Bateen Wood, Abu Dhabi and one if on 10 April at Ras Ghanada.
Indian House Crow Corvus splendens Common resident in north and east.
Brown-necked Raven Corvus mficollis Local resident of desert areas.
Pied Mynah Sturnus contra Local resident in Dubai.
Rose-coloured Starling Sturnus rose us Regular on autumn passage. Two juveniles on 24 September at Al Wathba.
Common Mynah Acridotheres tristis Common resident in urban areas. On 27 September 1156 were counted on their way to roost near the East Lagoon in Abu Dhabi (17.50-18.20 hrs).
Bank Mynah Acridotheres ginginianus Locally common resident. On 27 September a single flock of 12 individuals was seen while on their way to roost near the East Lagoon in Abu Dhabi (17.50-18.20 hrs).
House Sparrow Passer domesticus Ubiquitous.
Village Weaver Ploceus cucullatus One if on 12 April at the Zabeel ponds.
Pale Rock Sparrow Petronia brachydactyla Regular passage spring migrant, scarce in autumn. Five on 30 April at Khor Kalba.
Yellow-throated Sparrow Petronia xanthocollis Fairly common summer visitor, scarce migrant. Several at Al Wathba on 9 April, small groups on 15 April at Al lazirah.
(ndian Silverbill Euodice malabarica Widespread resident.
Common Rosefinch Carpodacus erythrinus Scarce in autumn, rare in spring. One red if on 10 May singing at the Emirates Golf Course.
Cinereous Bunting Emberiza cineracea Rare migrant mainly in spring. One !j1 on 15 April at AI lazirah.
98 Waders and other waterbirds in the United Arab Emirates
Ortolan Bunting Emberiza hortulana Fairly regular in spring and autumn. Five on 24 September at Al Wathba, several there on 9 April.
Black-headed Bunting Emberiza melanocephala Uncommon migrant, usually in autumn. One d' on 15 April at Al lazirah.
Table 10.1 Bird species observed between 7 April and 11 May 1995 in the United Arab Emirates . • = observed, . = not observed at this locality on this date. For localities see end of table. KO = Khor Oubai.
April May s~ecies 7 8 9 10 13 14 15 16 17 21 23 27 30 1 3 KO
Little Grebe Persian Shearwater • Sooty Shearwater • Great Cormorant • Socotra Cormorant • Little Bittern • Night Heron Little Green Heron • Indian Pond Heron • • Cattle Egret • Western Reef Heron Little Egret • • • • • • • • • • Great White Egret • Grey Heron • Spoonbill • • Greater Flamingo • • Mallard • • Pintail • Shoveler • Black Kite Marsh Harrier Pallid Harrier • • Montagu's Harrier • Lesser Sand Plover Greater Sand Plover • • • • • • • • • • • • Pacific Golden Plover • • • • • Grey Plover • Red-wattled Lapwing • • • • • • • • • • • • Sanderling Little Stint • • • • • Temminck's Stint • • • • • • Curlew Sandpiper • Dunlin • • • • • • • Broad-billed Sandpiper • • • • • • • • • Ruff • • • Common Snipe Pintail Snipe
99 AvifjlUna
April May s~ecies 7 8 9 10 13 14 15 16 17 21 23 27 30 I 3 KD Black-tailed Godwit Bar-tailed Godwit • Whimbrel • • • • • • • • • Curlew • • • • • • • • Redshank • • • • • • • • • Greenshank • • • • • • • • • • Green Sandpiper • • • • • • • • • Slender-billed Gull Lesser black-backed Gull • • Yellow-legged Gull • Gull-billed Tern • • • • Caspian Tern • • • • • • Swift Tern • • • Lesser Crested Tern Sandwich Tern • • Common Tern • White-cheeked Tern • Bridled Tern • • Little Tern • • Saunder's Little Tern • White-winged Black Tern • • • • Lichtenstein's Sandgrouse Chestnut-bellied Sandgrouse • Feral Pigeon • • • • • Collared Dove • • • • • • Turtle Dove • • • • • • • • Palm Dove • • • Rose-ringed Parakeet • • • • • • • • • • Little Owl • • • • • • • Richard's Pipit Blyth's Pipit Tawny Pipit Tree Pipit • Red-throated Pipit • Yellow Wagtail • • • White Wagtail • White-cheeked Bulbul Yellow-vented Bulbul • • • • • • Red-vented Bulbul • Rufous Bush Chat • • • • • • • Nightingale • White-throated Robin • Redstart • • • • • • • • Whinchat • lsabelline Wheatear • • • • European Wheatear • • Pied Wheatear • • • • Hooded Wheatear • Hume's Wheatear • 100 Waders and other waterbirds in the United Arab Emirates
April May sEecies 7 8 9 10 13 14 15 16 17 21 23 27 30 I 3 KD Rock Thrush Graceful Warbler • • • • Great Grey Shrike • • • • Steppe Grey Shrike • • • • Masked Shrike Indian House Crow • Brown-necked Raven • Pied Mynah • Common Mynah Bank Mynah • House Sparrow • • • • • • • • • • • Pale Rock Sparrow • Yellow-throated Sparrow • • Indian Silverbill • Cinereous Bunting • Ortolan Bunting • Black-headed Bunting •
April Locality
7 Ras Ghanada 8 Saffa Park 9 Al Wathba 10 Ras Ghanada 13 Ras Ghanada 14 JebeJ Ali 15 Al Jazeera 16 Abu Al Abyadh 17 Khor al Beidah 2! Ras Ghanada 23 Jebel Dhanna 27 Ras Ghanada 30 KhorKalba
May
Ziqt Dam 3 Ras Ghanada
IO! Avi[auna
Table 10.2 List of bird species observed in small numbers in Khor Dubai between 4 April and 11 May 1996 . • = observed, . = not observed on this date. Other waterbirds are discussed in chapter 6.
April May sEecies 7 8 12 18 24 25 28 4 7 J I Great Cormorant • • Great White Egret • • PintaiJ • ShoveJer • Marsh Harrier • • Spotted Eagle • • • Osprey • • Peregrine Falcon • Black-winged Stilt • Collared Pratincole • Greater Sand Plover • • Black-tailed Godwit • • • Arctic Skua • Great Black-headed Gull • Little Tern •
102 Waders and other waterbirds in the United Arab Emirates
REFERENCES
Anonymus 1987. Shorebirds on Khor Dubai. Dubai Shorebird Project. Report University of Durham. Aspinall S. 1995. United Arab Emirates. In: Scott, D.A. (ed.). A Directory of Wet lands in the Middle East: 469-527. ruCN, Gland, Switzerland & IWRB, Slimbridge, UK. Aspinall S. 1996a. Status and conservation of the breeding birds of the United Arab Emirates. Hobby Publications, Liverpool, Dubai. Aspinall S. 1996b. Time for a protected network in the UAE. Tribulus 6: 5-9. Barter M. 1986. Sex-related differences in adult Curlew Sandpipers Calidrisferruginea caught in Victoria. Stilt 8: 2-8. Basson P.W., J.E. Burchard, J.T. Hardy & A.R.G. Price 1981. Biotopes of the western Arabian Gulf. Harlow. Boer B. & J. Warn ken 1996. Flora of the Jubail Marine Wildlife Sanctuary, Saudi Arabia. In: F. Krupp, A.H. Abuzinada & L.A. Nader (eds.). A Marine Wildlife Sanctuary for the Arabian Gulf. Environmental Research and Conservation Following the 1991 Gulf War Oil Spill: 290- 295. NCWCD, Riyadh & Senckenberg Research Institute, Frankfurt a. M. Boere G.c. & C.J. Smit 1981. Bar-tailed Godwit Limosa lapponica. In: C.J. Smit & G.c. Boere (eds.). Birds of the Wadden Sea: 170-179. Rotterdam. Bundy G. & E. WaIT 1980. A check-list of the birds of the Arabian Gulf states. Sandgrouse I: 4-49. Butler R.W., T.D. Williams, N. Warnock & M.A. Bishop 1997. Wind assistance: a requirement for migration of shorebirds? Auk 114: 456-466. Cramp S. & K.E.L. Simmons 1983. Handbook of the birds of the western Palearctic. Band III. Waders to Gulls. Oxford, New York. Davidson N.C. 1984. How valid are flight range estimates for waders? Ring. & Migr. 5: 49-64. De Goeij PJ. 1993. Turnstone Arenaria interpres. In: H.W. Spiekman, G.O. Keij 1& P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 97-100. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands. DSP 1987. Shorebirds on Khor Dubai. Dubai Shorebird Project Report 1987. University of Durham, UK. Elliott C.C.H., M. Waltner, L.G. Underhill, J.S. Pringle & W.J.A. Dick 1976. The migration system of the Curlew Sandpiper Calidrisferruginea in Africa. Ostrich 47: 191-213. Etheridge B. 1971. Weights and measurements of waders wintering in the Tmcial States, Arabia. Wader Study Group Bull. 3: 5-7. Evans MJ. (ed.) 1994. Important bird areas in the Middle East. BirdLife Conservation Series No. 2. Norwich, UK. Evans M.I. & G.O. Keijl 1993a. Spring migration of coastal waders through the Saudi Arabian Gulf in 1991. Sandgrouse 15: 56-84. Evans M.I. & G.O. Keijl 1993b. Impact of Gulf War oil spills on the wader populations of the Saudi Arabian Gulf coast. Sandgrouse 15: 85-105. Fry G. 1989. Biometrics, moult and migration of Broad-billed Sandpipers Limicolafalcinellus spending the non-breeding season in northwest Australia. Stilt 15: 29-33. Geene R., P.L. Meininger & R. van Westricncn 1994. Passage of Eurasian waders through northern Egypt, spring 1990. In: P.L. Meininger & G.A.M. Atta (cds.). Ornithological studies in Egyptian wctlands 1989/90: 99-133. FORE-report nr. 94-0 I. WIWO-report 40, Zeist, The Netherlands. Ginn H.B. & D.S. Melville 1983. Moult in birds. ETO guide 19. British Trust for Ornithology, Tring. Glutz von Blotzheim U.N., K.M. Bauer & E. rlezzel 1975. Handbuch der Vogel Mitteleuropas. Akademische Vcrlagsgesellschaft, Band 6. Charadriifonnes (\. Teil). Pp. 744-760. Wiesbaden.
103 References
Green M., M. McGrady, S. Newton & 1. Uttley 1992. The shorebirds of Barr al Hikrnan and Ghubbat al Hashish, Oman. Unpublished report. Green M., M. McGrady, S. Newton & 1. Uttley 1994. Counts of shorebirds at Barr al Hikrnan and Ghubbat al Hashish, Oman, winter 1989-90. Wader Study Group Bull. 72: 39-43. Hayman P., 1. Marchant & T. Prater 1986. Shorebirds. An identification guide. London. Hirschfeld E. 1994. Migration patterns of some regularly occurring waders in Bahrain 1990-1992. Wader Study Group Bull. 73: 36-49. Hulscher 1.B. 1982. The Oystercatcher Haematopu~ ostralegus as a predator of the bivalve Macoma balthica in the Dutch Wadden Sea. Ardea 70: 89-152. Hustings F. (ed.) 1994. Bird census in the KlzIllrmak delta, Turkey, in 1992. WIWO-report 45, Zeist, The Netherlands. Isenmann P. & M.P. Bouchet 1993. l'Aire de distribution tTan
104 Waders and other waterbirds in the United Arab Emirates
Panov E.N. 1995. Superspeicies of shrikes in the former USSR. Proc. We st. Found Vert. Zool. 6: 26- 33 . Panow E.N. 1996. Die Wiirger der Palaarktis. Gattung Lanius. Magdeburg. Pienkowski M.W. & WJ.A. Dick 1975. The migration and wintering ofDunlin Calidris alpina in northwest Africa. Ornis Scand. 6: 151-167. Piersma T. 1985. Wader studies, and waterbirds, in the Nakdong Estuary, South Korea, in September 1984. WIWO-report 7, Zeist, The Netherlands. Piersma T. 1996. Plovers Charadriidae. Pp. 384-409. In: 1. del Hoyo, A. El1iott & l . Sargatal (eds.). Handbook of the birds of the world. Volume 3. Hoatzin to Auks. Lynx Edicions, Barcelona. Piersma T., M. Klaassen, l.H. I3ruggemann, A.-M. Blomert, A. Gueye, Y. Ntiamoa-Baidu & N.E. van Brederode 1990a. Seasonal timing of the spring departure of waders from the Banc d'Arguin, Mauritania. Ardea 78: 123-134. Piersma T., L. Zwarts & J.H. Bruggeman 1990b. Behavioural aspects of the departure of waders before long-distance flights: flocking, vocalizations, flight paths and diurnal timing. Ardea 78 : 157-184. Platt J.B. 1994. Greater Flamingos Phoenicopterus ruber at Khor Dubai, United Arab Emirates. Sandgrouse 14: 72-80. Prater AJ., J.H. Marchant & J. Vuorinen 1977. Guide to the identification and ageing of Holarctic waders. BTO guide 17. British Trust for Ornithology, Tring. Puttick G.M. 1981. Curlew Sandpiper Calidrisferruginea foraging related to prey availability. In : J. Cooper (ed.). Proc. symp. birds of the sea and shore: 116. African Seabird Group Cape Town, South Africa. Richardson C. 1990. The birds of the United Arab Emirates. Hobby Publications, Dubai & Warrington. Richardson C. 1994. Systematic list of species reported in 1993. Emirates Bird Report 18: 18-87. Richardson c., Aspinall S. & P. Hellyer 1994. United Arab Emirates. In : M.l. Evans (ed.). Important bird areas in the Middle East: 333-349. BirdLife Conservation Series No. 2. Norwich, UK. Rose P.M. & D.A. Scott 1994. Waterfowl Population Estimates. IWRB Publication 29. Slimbridge. Ruiters P.S. 1993. Grey Plover Pluvialis squatarola. In: H.W. Spiekman, G.O. Keijl & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 55-59. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands. Salvig l.C., Asbirk S., Kjeldsen J.P. & Rasmussen P.A.F. 1994. Wintering waders in the Bijagos archipelago, Guinea-Bissau 1992-1993. Ardea 82: 137-142. Schekkerman H. & M.W.J. van Roomen (eds.) 1993. Migration of waterbirds through wetlands in Central Anatolia, spring 1988. WIWO-report 32. Zeist, The Netherlands. Skakuj M. & T. Stawarczyk 1997. Wader and non-passerine ringing. In: E. Hirschfeld, T. Stawarczyk, J. Lontkowski, M. Skakuj, G. Keijl, P. Ruiters, M. Fouquet, O. Girard & S. Aspinall. Abu Dhabi shorebirds project 1994: 6-15. Environmental Research and Wildlife Development Agency External Report no. 1, Abu Dhabi. Smart 1., G.A. Miles & M. West 1983. Waders and waterbirds on Dubai creek. Wader Study Group Bull. 37: 29-30. Spiekman H.W. 1993a. Oystercatcher Haematopus ostralegus. In: H.W. Spiekman, G.O. Keij1 & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 45-47. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands. Spiekman H.W. 1993b. Dunlin Calidris a/pina. In: H.W. Spiekman, G.O. Keijl & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 74-78. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands.
105 References
Stegeman L. 1993. Greenshank Tringa nebularia. In: H.W. Spiekman, G.O. Keijl & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 93-94. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands. Stikvoort E.e. 1994. Stomach and faeces contents of waterbirds in Egypt. In: P.L. Meininger & G.A.M. Atta (eds.). Ornithological studies in Egyptian wetlands 1989190: 194-212. FORE report nr. 94-01. WIWO-report 40, Zeist, The Netherlands. Svensson B.W. & P. Tomkovich 1997. Broad-billed Sandpiper Limicolafalcinellus. In: WJ.M. Hagemeijer & MJ. Blair 1997 (eds.). The EBCC atlas of European breeding birds. Their distribution and abundance: 282-283. T. & A.D. Poyser, London. Tucker G. 1985. Autumn wader migration in Bahrain. Wader Study Group Bull. 44: 30-32. Tulp l., S. McChesney & P. de Goeij 1994. Migratory departures of waders from Northwestern Australia: behaviour, timing and possible migration routes. Ardea 82: 201-221. Turpie 1.K. & P.A.R. Hockey 1993. Comparative diurnal and nocturnal foraging behaviour and energy intake of premigratory Grey Plovers Pluvialis squatarola and Whimbrels Numenius phaeopus in South Africa. Ibis 135: 156-165. Uhlig R. 1984. Zum Durchzug des Sumpflaufers (Limicolafalcinellus [pONT.]) in Bulgarien. Faun. Abh. Slaat!. Mus. Tierk. Dresden 12: 69-80. Uttley 1.0., C.J. Thomas, M.G. Green, D. Suddaby & J.B. Platt 1988. The autumn migration of waders and other waterbirds through the northern United Arab Emirates. Sandgrouse 10: 58-70. Van der Have T.M., V.M. van den Berk, J.P. Cronau & M.1. Langeveld (eds.) 1988. South Turkey Project. A survey of waders and waterfowl in the <;:ukurova deltas, spring 1987. WIWO report 22. Zeist, The Netherlands. Van der Winden J., I.I. Chemichko, T.M. van der Have, V.D. Shiokin & Y. Verkuil Y. 1993. The migration of Broad-billed Sandpiper Limicolafalcinellus during May 1992 in the Sivash, Ukraine. Wader Study Group Bull. 71: 41-43. Van Gils 1. & P. Wiersma 1996. Sandpipers, snipes and phalaropes Scolopacidae. Pp. 444-533. In: 1. del Hoyo, A. Elliott & 1. Sargatal (eds.). Handbook of the birds of the world. Volume 3. Hoatzin to Auks. Lynx Edicions, Barcelona. Van Roomen M.WJ. 1993. Redshank Tringa totanus. In: H.W. Spiekman, G.O. Keijl & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wet lands, Tunisia: 89-91. Eastern Mediterranean Wader Project, spring 1990. WIWO-report 38, Zeist, The Netherlands. Verkuil Y., A. Koolhaas & J. van der Winden 1993. Wind effects on prey availability: how northward migrating waders use brackish and hypersaline lagoons in the Sivash, Ukraine. Neth. J Sea Res. 31: 359-374. Verkuil Y., S. van de Sant, E. Stikvoort, J. van der Winden & B. Zwinselman 1993. Feeding ecology of waders in the Sivash. In: T.M. van der Have, S. van de Sant, Y. Verkuil & J. van der Winden (eds.). Waterbirds in the Sivash, Ukraine, spring 1992: 39-63. WIWO-report 36, Zeist, The Netherlands. Voous K.H. 1973. List of recent holarctic species. Non-passerines.Ibis 115: 612-638. Voous K.H. 1977a. List of recent holarctic species. Passerines. Part l. Ibis 119: 223-250. Voous K.H. I 977b. List of recent holarctic species. Passerines. Part I!. Ibis 119: 376-406. Wellinga S.M. 1993. Curlew Sandpiper Calidrisferruginea. In: H.W. Spiekman, G.O. Keijl & P.S. Ruiters (eds.). Waterbirds in the Kneiss area and other wetlands, Tunisia: 65-74. Eastern Mediterranean Wader Project, spring 1990 WIWO-report 38, Zeist, The Netherlands. Wymenga E., M. Engelmoer, C.J. Smit & T.M. van Spanje 1990. Geographical breeding origin and migration of waders wintering in West-Africa. Ardea 78: 83-112. Zwarts L. 1974. Vogels van het brakke getijgebied. mu, Amsterdam.
106 Waders and other waterbirds in the United Arab Emirates
Zwarts L. 1985. The winter exploitation of Fiddler Crabs Uca tangeri by waders in Guinea-Bissau. Ardea 73: 3-12. Zwarts L., A.-M. Blomert, B.J. Ens, R. Hupkes & T.M. van Spanje 1990a. Why do waders reach high feeding densities on the intertidal flats of the Banc d'Arguin, Mauritania? Ardea 78: 39-52. Zwarts L. A.-M. Blomert & R. Hupkes 1990b. Increase of feeding time in waders preparing for spring migration from the Banc d'Arguin, Mauritania. Ardea 78: 237-256. Zwarts L. & S. Dirksen 1990. Digestive bottlenecks limits the increase in food intake of Whimbrels preparing their departure from the Banc d'Arguin, Mauritania, in spring Ardea 78: 257-278. Zwarts L. & P. Esselink 1989. Versatility of male Curlews Numenius arquata preying upon Nereis diversicolor: deploying contrasting capture modes dependent on prey availability. Mar. Eco/. Prog. Ser. 56: 255-269. Zwarts L., H. Felemban & R.G. Price 1991. Wader counts along the Saudi Arabian coast suggests the Gulf harbours millions of waders. Wader Study Group Bull. 63: 25-32.
107 APPENDIX 1. Numbers of waterbirds counted in September - October 1994 in the United Arab Emirates.
Eastern Khor Ad Ralat lebel Saksa'eet Khoral Jazirat KhorQurayyah Golf Lagoon Dubai Dab'iyyah lamilah Dhanna al Ya'en Beidah al Ramra Kalba Course 27-9 29-9 1-10 2-10 3-10 3-10 5-10 6-10 9-10 9-10 10-10
Podiceps nigricollis 3 Phalacrocorax carbo Phalacrocorax nigrogularis 18 40,000 I~ ~ ~ I::l Butorides striatus ::s t:l.. Ardeola grayii 2 0 Bubulcus ibis 2 16 ;;. ....'" Egretta garzetta 6 I I 3 ;f I::l Egretta gularis 2 65 26 12 8 5 147 30 8 ;;; Egretta alba 3 .... ::;.<:>- lxobrychus minutus 1 <:> ~ 00 Ardea cinerea 3 366 4 3 15 2 2 S· S. total herons 7 456 32 12 8 5 150 47 3 10 6 I'" ;;;~ Platalea leucorodia 6 t:l.. Phoenicopterus ruber 124 ....~ I::l Aythyaferina 9 <:>- Anascrecca 10 2 ~::;. Anas querquedula 3 5 ~ Anas platyrhynchos 4 '" HaematopZls ostralegus 114 70 4 4 3 36 21 Himantopus himantopZls 12 3 Dromas ardeola 115 Cursorius cursor Vanellus indicus 11 Vanellus leucurus I APPENDIX 1. Continued.
Eastern Khor Ad Halat Jebel Saksa'eet Khor al Jazirat KhorQurayyah Golf Lagoon Dubai Dab'iyyah Jamilah Dhanna al Ya'en Beidah al Hamra Kalba Course 27-9 29-9 1-10 2-10 3-10 3-10 5-10 6-10 9-10 9-10 10-10
Charadrius hiaticula 109 6 9 4 1 10 Charadrius alexandrinus 700 261 105 86 23 210 7 3 60 30 Charadrius mongolus 7 213 285 35 43 115 100 5 ~ }47 }50 i} Charadrius leschenaultii 6 1 ... Pluvialis folva 37 108 '"§ Pluvialis squatarola 2 225 77 21 9 3 81 3 .... Calidris alba 7 8 4 3 45 13 "So Cl) Calidris minuta 2 200 20 2 13 5 4 ... <: Calidris temminckii 2 3 ., ~ Calidris ferruginea 220 50 46 29 12 25 3 <:>-... Calidris afpina 1700 406 115 89 314 275 185 2 ". 0 ~ \0 Limicola falcinellus 8 22 52 s· Philomachus pugnax 6 20 So Gallinago gallinago 25 Cl) Gallinago stenura 3 ~ ~. Limosa limosa 73 3 4 .... Limosa lapponica 249 72 62 20 19 216 52 2 8 .,:...... Numenius phaeopus 4 2 1 12 1 4 4 "'"t>J Numenius arquata 41 72 2 3 2 9 5 4 :: Tringa tot anus 22 193 33 12 7 218 275 2 23 2 .,". Tringa stagnatilis 2 I ~ Tringa nebularia 3 23 2 6 3 22 4 '"' Tringa glareola Xenus cinereus 9 3 5 24 13 19 47 Actitis hypoleucos 12 2 1 4 4 15 Arenaria interpres 21 14 26 3 22 20 Phalaropus lobatus APPENDIX 1. Continued.
Eastern Khor Ad Halat lebel Saksa'eet Khor al lazirat KhorQurayyah Golf Lagoon Dubai Dab'iyyah Jamilah Dhanna al Ya'en Beidah al Harnra Kalba Course 27-9 29-9 1-10 2-10 3-10 3-10 5-10 6-10 9-10 9-10 10-10
small waders 500
total waders 71 3980 1924 717 380 481 1305 734 19 152 242 I~1} ~ Larus hemprichii s:::. Larus ridibundus 2 ~ Larus gene; 47 40 665 1I 9 12 10 c ~ Larus fuse us 3 ~ :;; Larus eaehinnans 1100 5 27 2 330 s:::.
~ <::I- total gulls 1 1149 45 665 39 11 345 0 10 1 '" ~ 0 GelochelidoYl nilotica 5 8 48 8 ;:' S. Sterna caspia 38 2 2 2 ... Sterna bergii 7 3 ~ Sterna bengalensis 4 2 9 40 + ~ Sterna sandvicensis 2 10 :,.. ~ Sterna hirundo 20 s:::. } 12 <::I- Sterna repressa I 34 300 ~ Sterna saundersi 10 39 18 12 15 ~ . Chlidonias hybl"ida to terns 400 '"
total terns 5 59 41 0 58 4 60 36 388 400 1
grand total 84 5789 2043 1394 503 491 41,526 1163 413 572 269 Waders and other waterbirds in the United Arab Emirates
APPENDIX 2. Numbers of waterbirds and raptors counted in wetlands of the United Arab Emirates, January 1995 (S. Aspinall). Raptors and Kingfisher are not included in the grand total. locality Jebel AbuAI Ad eastern Bel AI Dhanna Merawah Ab~'adh Oab'in:ah la800n Ghelam Ghar Phalacrocorax carbo I 8 10 1 I 2 Phalacrocorax nigrogularis - 100
Bubulcus ibis 68 Egretla gular is 52 164 I1 14 7 Egretta alba 2 Ardea cinerea 1 4 15 2 3 total herons 2 56 179 12 86 10 0
Plegadis falcinellus 2 Phoenicopterus ruber 61 52 49 Alopochen aegyptiacus 11 2 Anas penelope Anas crecca 12 Anas platyrhynchos 19 34 Anas acuta 7 Anas clypeata 78 Grus grus 2
Haematopus ostralegus 2 78 60 49 56 Dromas ardeola 528 2 Himantopus himantopus 97 Cursorius cursor Charadrius hiaticula 3 16 22 Charadrius dubius 2 Charadrius alexandrinus 27 199 45 158 90 100 1380 Charadrius mongolus 8 834 420 338 50 350 Charadrius leschenaultii 37 25 76 100 10 Charadrius spec. 505 824 200 Pluvialis squatarola 932 195 98 3 36 4 Calidris tenuirostris 54 Calidris alba 5 13 61 10 3 Calidris minuta 2 3 1175 Calidris temminckii 4 Calidris ferruginea 2 17 116 25 I Calidris afpina 43 809 1603 557 300 3 Calidris spec. 360 Limicolafalcinellus Philomachus pugnax 18 Gallinago gal/inago Limosa lapponica 9 1552 656 330 91 Numenius phaeopus 3 45 6 3 Numenius arquata 2 12 69 42 9
111 Waders and other waterbirds in the United Arab Emirates
APPENDIX 2. Continued. locality Khor Khor Jazirat Dibba- Golf Course Dubai aJ Beidah aJ Hamra Khor Kalba Calidris a/pina 2 5330 54 15 15 Calidris spec. 650 Limico/a falcinel/us 509 Phi/omachus pugnax 32 2 2 Lymnocryptes minimus 1 Gallinago gallinago 2 2 Gallinago stenura 4 Limosa lapponica 538 415 22 Numenius phaeopus 37 Numenius arquata 62 57 65 Tringa totanus 16 458 395 206 30 Tringa stagnatilis I I Tringa nebu/aria 8 46 90 2 Tringa ochropus 1 Tringa glareola I Xenus cinereus 8 19 16 68 1 Actitis hypoleucos 2 I 2 Arenaria interpres 10 4 71 total waders 167 11,843 2111 1411 104
Larus hemprichii 11 Larus ichthyaetus 1 34 14 Larus ridibundus 1 3700 2000 4250 Larus genei 8 244 58 332 Larus cachinnans 4200 1504 1 1177 Larus juscus 1 Larus spec. 200 total gulls 9 8146 3564 567 5452
Gelochelidon nilotica 8 72 17 Sterna repressa 390 Sterna hirundo 12 2 Sterna bengalensis 6 93 Sterna sandvicensis 11 297 Sterna saundersi 2 8 Chlidonias hybridus 46 Sterna spec. 100 total terns 0 20 139 125 780
Pandion haliaetus 3 2 Circus aeruginosus 3 3 Circus macrourus 1 Falco peregrinus I Alcedo atthis 3 grand total 235 21,171 6416 2191 6782
114 APPENDIX 3. Numbers of waterbirds and raptors counted in wetlands of the United Arab Emirates, April-May 1995. For numbers in Khor Dubai, see Appendix 4. Raptors are not included in the grand total.
date 23 April 23 April 18 April 16 Apr 17 April 14 April 17 April locality Jebel AbuAI Ad Emirates Dhanna Merawah Abz:adh Dab'i~ah Bel Ghelam AI Ghar Golf Course Phalacrocorax nigrogularis 1
Butorides striatus 2 ~ Egretta gularis 4 6 6 2 ~ ~ I:> Phoenicopterus ruber 81 2 108 Grus grus 1 I~ '" Haematopus ostralegus 3 13 9 33 8 :;:'" Himantopus himantopus 127 ~ '" Dromas ardeola 113 195 55 "'"::;. Charadrius hiaticula 29 34 ~ Lro Si' Charadrius dubius 3 5 ;;. Charadrius alexandrinus 21 4 6 15 10 200 4 '" Charadrius mongolus 32 150 364 90 230 2 ~ Charadrius leschenaultii I 16 ~. I:>.. Pluvialis fiAva ::... Pluvialis squatarola 15 125 40 90 15 '"I:> Vanellus indicus 5 "'"t>'l Calidris alba 8 25 163 100 ::;.::. ~ Calidris minuta 17 249 24 Cl> Calidris temminckii 8 '" Calidris ferruginea 4 15 30 10 20 Calidris alpina 38 110 614 150 40 3 Limicola falcinellus Philomachus pugnax 23 4 Gallinago gallinago 16 Gallinago stenura Limosa lapponica 5 566 154 145 106 APPENDIX 3. Continued.
date 23 April 23 April 18 April 16 Apr 17 April 14 April 17 April locality lebel AbuAI Ad Emirates Dhanna Merawah Ab~adh Dab'iyyah Bel Ghelam Al Ghar Golf Course Numenius phaeapus 3 I 4 9 Numenius arquata 2 17 9 4 Tringa tatanus 3 36 145 4 3 2 Tringa nebularia I 4 I I 8 Tringa glare ala 3 11>~ Xenus cinereus 10 3 4 2l ;:,;c Actitis hypoleucas 4 I:l.. c Arenaria interpres 3 32 71 8 2 :i- Phalarapus lobatus 9 2 11>..., unidentified waders 200 720 :;;: total waders 142 1402 2510 746 456 678 107 ~..., "":::;. Larus genei ~ 0\ Si· :i- Sterna repressa 20 50 180 ll> Sterna caspia 4 4 ~ Sterna bengalensis 12 50 ~. I:l.. Sterna saundersi 46 17 3 1 ::...... , total terns 20 112 247 7 1 0 0 c "" ~ Pandion haliaetus 2 I~. grand total 166 1603 2766 756 458 787 107 ,'" APPENDIX 3. Continued.
date 10 May 17 April 6 May 6 May 15 April 11 April 8 May locality Emirates Khor al Khor al garbage Jazirat Khor Khor Golf Course Beidah Beidah dumE K.a.B. al Hamra Kalba Kalba Phalacrocorax carbo I Pha/acrocorax nigrogularis 7
Ixobrychus minutus 3 ~ Nycticorax nycticorax I ~ BUlorides striatus 3 ;:; § Egretta gularis 15 20 1/ s:::.... Egrelta garzetta I c S- Ardea cinerea 2 3 6 ...'" total herons 4 IS 22 0 14 10 0 ~ ... Phoenicopterus ruber 25 95 "t)-=; . Crex crex a.- -.l s· S- Haematopus ostralegus 25 3 '" Himantopus himantopus 2 ~ Dromas ardeo/a ~. s:::.... Glareola pratincola I ::.... Charadrius dubius I 2 I ~ '>- Charadrius alexandrinus 20 58 38 4 12 21 4 Charadrius mongo/us 63 679 I 19 8 ~=;. Pluvialis fulva 2 t:l Pluvialis squatarola 178 45 33 2 "c.., Vanellus indicus 4 4 2 Calidris alba 13 4 2 42 20 Calidris minuta 2 75 I Calidris temminckii I Calidris ferruginea 3 29 1 Calidris alpina 166 3 85 Limosa limosa 4 APPENDIX 3. Continued. date 10 May 17 April 6 May 6 May 15 April 11 April 8 May locality Emirates Khor al Khor al garbage Jazirat Khor Khor Golf Course Beidah Beidah dum~ K.a.B. al Hamra Kalba Kalba Limosa lapponica 491 48 56 Numenius phaeopus 13 4 12 Numenius arquala 5 9 4 12 Tringa lotanus 43 1 1 15 23 39 5 Tringa nebularia 23 3 4 ~ Tringa glareola 2 ~ Xenus cinereus 50 29 IS 25 8 2 ~ § AClitis hypoleucos 2 1 2 2 t:>.. Arenaria interpres c 23 30 5 So Phalaropus lobatus 3 ...'" total waders 33 1153 930 133 267 147 45 ~ ...~ Larus hemprichii 1160 3000 """' Lams ichthyaetus 1 ~ 00 Larus ridibundus :sO So Larus genei 2 '" Larns cachinnans 2 ~ Larns sabini 1 ~. total gulls 0 0 0 0 2 1163 3004 t:>.. :>...... ~ Stercorarius parasitic us 6 I"""' ~ Gelochelidon nilotica 5 30 Sterna repressa 200 100 li' Sterna himndo 1000 1000 Sterna bengalensis 10 1 Sterna sandvicensis 5 10 Sterna saundersi I 2 1 total terns 0 6 0 30 1 1364 1112
grand total 38 1206 1047 163 284 2691 4161 Waders and other waterbirds in the United Arab Emirates
APPENDIX 4. Numbers of water birds and raptors counted in Khor Dubai, April-May 1995. * = not counted. The count on 18 May was performed by Simon Aspinall and Colin Richardson. Raptors are not included in the grand total.
April May 12 18 25 28 4 7 11 18 Phalacrocorax carbo 8 2 2 1
Egretta gularis 10 8 4 10 6 8 2 10 12 Egretta garzetta Egretta alba 4 1 1 Ardea cinerea 50 51 75 99 92 * * 93 45 total herons 64 60 79 110 98 * * 103 57
Platalea leucorodia 8 9 7 7 7 7 7 5 1 Phoenicopterus ruber 375 383 400 416 393 438 410 400 399 Anas acuta 2 2 3 1 Anas clypeata 3
Haematopus ostralegus 67 74 44 38 11 9 15 19 18 Himantopus himantopus 1 Glareola pratincola 1 1 Charadrius hiaticula 51 85 21 54 30 22 8 5 Charadrius dub ius 1 1 Charadrius alexandrinus 68 110 93 262 217 274 282 235 330 Charadrius mongolus 760 932 859 1263 854 606 508 219 122 Pluvialis fulva 47 84 62 155 163 162 100 86 12 Pluvialis squatarola 317 478 384 443 422 436 399 64 37 Calidris alba 7 1 [ 21 22 14 12 17 3 Calidris minuta 77 229 118 374 2[5 141 42 [9 1 Calidris ferruginea 583 975 1660 968 983 434 365 72 28 Calidris alpina 131 123 119 41 10 12 12 [4 Limicola falcinellus 46 63 30 50 22 14 18 14 12 Philomachus pugnax 1 1 Limosa limosa [ Limosa lapponica 345 346 461 384 84 25 17 9 12 Numenius phaeopus 1 1 Numenius arquata 4 8 8 5 8 6 8 12 2 Tringa totanus 8 9 9 6 6 6 11 6 1 Tringa nebularia 2 4 2 3 3 5 1 3 Xenus cinereus 6 10 36 104 47 65 68 124 19 Ac/j/is hypoleucos 1 Arenaria interpres 8 15 17 29 43 33 18 43 2 Phalaropu5 lobatus 2 total waders 2522 2552 3935 4204 3141 2263 1889 960 604
119 Waders and other waterbirds in the United Arab Emirates
Larus ichthyaetus 2 4 3 3 3 Larus ridibundus 3 22 I I 2 3 Larus genei 97 84 51 78 61 25 49 57 48 Larus cachinnans 42 9 10 4 2 2 total gulls 144 119 52 92 68 32 51 63 48
Stercorarius parasiticus
Gelochelidon nilotica 16 13 6 11 8 6 7 10 IS Sterna repress a Sterna hirundo 4 2 Sterna caspia 54 23 27 7 22 14 12 20 8 Sterna bengalensis Sterna sandvicensis 40 43 95 81 43 65 50 62 7 Sterna saundersi 2 3 1 1 total terns 110 91 135 99 77 86 69 92 31
Pandion haliaetus 1 2 2 5 2 2 Circus aeruginosus 2 2 Aqui/a clanga 2 Falco peregrinus grand total 3234 3216 4609 4932 3787 2839 2430 1623 1140
120 Waders and other waterbirds in the United Arab Emirates
APPENDIX 5. Numbers of waterbirds counted at Ras Ghanada, April-May 1995.
10 April 21 April 2 May 10May Egretta gularis 2 7 5 Alopochen aegyptiacus 2 Charadrius hiaticula 1 Charadrius alexandrinus 2 14 27 8 Charadrius mongolus 16 34 7 Pluvialis squatarola 2 4 10 4 Calidris minuta 3 16 Calidris ferruginea 13 37 Calidris alpina 41 13 7 Calidris spec. 8 Limicola falcinellus 6 Limosa lapponica 1 2 16 6 Numenius phaeopus 3 4 Numenius arquata 3 2 Tringa totanus 1 2 5 1 Tringa nebularia 1 2 Xenus cinereus 8 9 27 24 Arenaria interpres 1 15 3 Gelochelidon nilotica 1 1 grand total 27 117 216 71
121 Waders and other waterbirds in the United Arab Emirates
APPENDIX 6. Waders departing, or attempting to depart, from Khor Dubai, United Arab Emirates, in spring 1995. Species are ranked according to mid-point of breeding latitude from south to north. Mid-point of breeding latitude is estimated from maps from Cramp & Simmons (1983) and from Hayman et al. (1986). For Charadrius mongolus it is assumed that the subspecies pamirensis is involved. For estimation of breeding latitude for species also breeding east from the Western Palearctic it is assumed that they originate from breeding areas east of the Kola Peninsula. species date number per flock breeding latitude (ON) Charadrius mongo/us 2 May 40 30 Tringa nebularia 2 May 6 60 Tringa nebularia 4 May 3 Xenus cinereus 4 May 5 60 Xenus cinereus 4 May 3 Xenus cinereus 4 May 5 Limicola falcinellus I May 16 66 Limicola falcinellus 4 May 11 Charadrius hiaticula 2 May 3 68 Charadrius hiaticula 4 May I Charadrius hiaticula 7 May 4 Calidris temminckii 1 May 3 70 Calidris temminckii 2 May 2 Limosa lapponica 30 April 65 70 Limosa lapponica 30 April 50 Limosa lapponica 30 April 70 Philomachus pugnax 2 May 70 Calidris alpina 8 April 110 73 Calidris minuta 2 May 10 73 Calidris minuta 2 May 18 Calidris minuta 4 May 18 Calidris minuta 4 May 17 Calidris minuta 4 May 5 Calidris minuta 7 May 5 Calidris minuta 7 May 9 Pluvialis julva 30 April 58 73 Pluvialis squatarola 2 May 6 73 Pluvialis squatarola 2 May 95 Calidris ferruginea 29 April 80 75 Calidris ferruginea 30 April 70 Calidris ferruginea I May 70 CalidrisferruRinea 2 May 40 Calidris ferruginea 2 May 60 Calidris ferruginea 4 May 45 Calidl'is ferruginea 4 May 26 Calidris ferruginea 4 May 60 Calidris ferruginea 4 May 20 Calidrisferrllginea 7 May 42 Calidrisferrllginea 7 May 42
122 Waders and other wa/erbirds in the United Arab Emirates
APPENDIX 7. Waders departing, or attempting to depart, from the lubail lagoons, Saudi Arabia, in spring 1991. See further appendix 6. species date number per flock breeding latitude eN) Charadrius mongolus 16 May 5 30 Charadrius mongolus 20 May 18 Charadrius mongolus 20 May 6 Glareola pralincola 10 April 6 40 Glareola pratincola II April 5 Glareola pratincola 13 April 6 Glareola pratincola 16 April 4 Glareola pratincola 29 April 3 Glareola pratincola 30 April 7 Glareola pratincola 4 May 3 Glareoia pratincoia 8 May I Glareola pratincola 14 May I Recurvirostra avosetta 16 May 1 40 Himantopus himan/opus 20 May 2 45 Charadrius dub ius 17 April 4 50 Tringa totanus 9 April 24 50 Tringa totanus 19 April 5 Tringa totanus 21 April 21 Tringa to/anus 8 May 8 Tringa lo/anus 21 May 6 Numenius arquata 28 April I 55 Numenius arquata 28 April I Numenius arquata 28 April 2 Numenius arquata 28 April 2 Numenius arquata 28 April 2 Numenius arqua/a 28 April 1 Numenius arquata 29 April 5 Numenius arquata 29 April 2 Tringa stagnatilis 23 April 15 55 Tringa glareola 8 May 3 60 Tringa glareola 8 May 3 Tringa glareola 14 May 14 Tringa glareola 15 May 2 Tringa glareola 21 May 4 Xenus cinereus 20 May 2 60 Limicola falcinellus 2 May 25 66 Limicola falcinellus 13 May 23 Limicolafaicinellus 14 May 6 Limicolafalcinellus 16 May 9 Limicola fulcinellus 19 May 20 Limicola falcinellus 20 May 10 Limosa lapponica 8 May 1 70 Limosa lapponica 14 May 4 Philomachus pugnax 8 May 7 70 Philomachus pugnax 8 May 8 Philomachus pugnax 14 May 8
123 Waders and other walerbirds in the United Arab Emirates
APPENDIX 7. Continued.
species date number per flock breeding latitude (ON) Philomachus pugnax 14 May 30 Philomachus pugnax 14 May 3 Philomachus pugnax 14 May I Pluvialis squatarola 12 May 26 70 Calidris alpina 8 May 50 73 Ca/idris alpina 14 May 15 Calidris alpina 20 May 5 Calidris a/pina 20 May 5 Calidris a/pina 21 May 8 Calidris minuta 13 May 30 73 Calidris minuta 13 May 40 Calidris minuta 13 May 10 Calidris minuta 13 May 20 Calidris minuta 13 May 10 Calidris minuta 13 May 30 Calidris minuta 14 May 5 Calidris minuta IS May 13 Calidris minuta 16 May 4 Calidris minuta 16 May 10 Calidris minuta 16May 26 Calidris minuta 20 May 11 Calidris minuta 20 May 39 Calidris minuta 20 May 36 Calidris minuta 20 May 16 Calidris minuta 20 May 15 Arenaria interpres 13 May 3 75 Arenaria interpres 16May 5 Arenaria inlerpres 16 May 2 Arenaria interpres 19 May 16 Arenaria interpres 20 May 2 Arenaria inlerpres 20 May 5 Calidris alba 6 May 8 75 Calidris ferruginea 4 May 3 75 Calidris ferruginea 7 May 70 Calidris ferruginea 13 May 40 Calidris ferruginea 14 May 52 Calidris ferruginea 14 May 16 Calidris ferruginea 14 May 120 Calidris !erruginea 14 May 30 Calidris ferruginea 14 May 2 Calidris ferruginea 15 May 7 Calidris ferrugineu 16May 35 Calidr;s !erruginea 20 May 15 Calidris ferruginea 20 May 21
124 Waders and other waterbirds in the United Arab Emirates
APPENDIX 8. Data of birds ringed between 12 April and 2 May 1995 in Khor Dubai, United Arab Emirates. Measurements are given in millimetres, weights in grams. Sex: 0 = unknown, I = male, 2 = female. Age: 4 = older than first calendar year, 5 = second calendar year, 6 = older than second calendar year. Plumage is given on a scale from 1 to 7: I = complete winter plumage, 2 = traces of summer plumage, 3 = Y. summer plumage, 4 = Y2 summer plumage, 5 = :y. summer plumage, 6 = traces of winter plumage, 7 = complete summer plumage. Sum = sum of score of individual primaries according to the system of Ginn and Melville (1983).
date sex a~e win~ bill tarsus wei~ht Qlum sum
Charadrius alexandrinus 11 April 2 4 107 15.2 28.3 36 50 12 April 0 4 I I I 16.6 26.0 40.5 50 29 April 4 110 17.2 30.3 I May 1 5 106 15.2 26.4 35.5 1 May 2 5 103 14.4 29.6 41 2 May 5 104 14.3 26.0 31 50 2 May 2 6 106 15.9 28.0 32.5 50 2 May 5 105 14.8 25.8 34 50
On 28 and 29 April also 19 pulli were ringed.
Charadrius mongolus /1 April 0 6 132 17.8 33.9 57 I 50 12 April 2 4 140 17.7 33.6 80.5 7 50 28 April 0 5 126 18.3 34.6 56 I 50 28 April 2 6 135 18.7 32.6 88 7 50 29 April 2 6 131 17.3 32.9 84 7 18 29 April 6 130 17.3 34.4 82 7 50 30 April 6 134 17.8 33.5 82 7 50 I May 2 6 133 16.2 33.1 91 6 0 I May 2 6 132 17.7 31.8 87 7 50 2 May 2 6 137 16.6 33.2 93 7 50 2 May 1 6 130 17.3 32.6 69 7 50 2 May 1 6 129 18.4 33 .0 88 7 50
Pluvialis squatarola I May 0 6 210 29.6 53.0 275 3 50
125 Waders and other waterbirds in the United Arab Emirates
Calidris ferruginea II April 0 6 132 36.5 30.4 56 5 SO 12 April I 6 135 37.1 30.8 58.5 4 50 12 April 0 6 136 41.2 30.3 ss 2 50 12 April 0 6 13R 36.4 31.7 59 6 50 12 April I 6 137 33.5 29.5 54 6 50 28 April 1 6 134 36.1 31.1 76 7 50 28 April 0 6 134 36.8 30.2 64 3 50 28 April 0 6 134 39.9 32.6 67 6 50 29 April I 6 134 36.5 29.7 74 7 50 29 April I 5 133 37.5 30.0 72 7 50 29 April 0 6 137 40.2 30.2 72 3 50 29 April 0 6 136 41.0 32.0 73 6 50 29 April I 6 137 39.0 33.9 81 7 50 29 April 2 6 135 40.6 32.3 75 7 50 29 April 2 6 134 39.4 32.1 71 7 50 29 April 1 6 133 34.1 30.5 70 7 50 30 April 2 6 134 42.0 30.7 72 7 50 30 April 1 6 139 38.2 32.7 85 7 50 30 April 2 6 136 43.1 32.2 72 7 50 30 April 2 6 136 36.8 31.1 83 7 50 30 April 0 6 134 35.8 30.1 72 7 50 30 April 1 6 132 34.4 30.1 69 7 SO 30 April 1 6 131 35.0 29.3 73 7 50 30 April 2 6 137 37.0 31.0 73 7 50 30 April 2 6 130 39.2 32.0 73 6 50 30 April 1 6 133 35.6 29.9 71 7 50 30 April 2 6 132 40.2 32.9 61 6 50 30 April 2 6 132 41.3 33.0 83 7 50 30 April 2 6 135 43 .9 32.8 61 7 50 I May I 6 136 42.4 33.8 79 7 50 1 May 2 6 133 43 .3 31.6 68 6 50 1 May 2 6 128 39.9 32.2 66 7 50 1 May 2 6 131 37.7 29.8 72 7 50 2 May 2 6 134 40.3 31.1 75.5 7 50 2 May 1 6 132 37.2 30.3 72 7 50
Calidris alpina 12 April 0 6 118 32.8 25.2 54.5 3 50
Calidris minuta 28 April 0 4 19.4 21.2 26.5 7 49 29 April 0 4 101 19.1 21.5 30 7 50 30 April 0 4 99 19.7 22.4 27 7 50 2 May 0 4 96 19.1 19.9 26.5 7 50
126 Waders and other waterbirds in the United Arab Emirates
Limicola jalcinellus 28 April 0 5 108 29.4 21.6 36.5 2 50 28 April 0 5 107 32.1 22.7 36.5 2 50 29 April 0 6 107 32 23.0 50 4 50 30 April 0 5 108 32.8 32.2 41 3 50
Limosa lapponica 11 April 2 6 226 96.6 59.1 300 50 12 April 6 213 77.3 50.6 232 7 50 28 April 5 200 68.1 51.4 214 8 30 April 6 218 73.9 50.6 275 7 50 30 April 6 215 75.4 44.0 300 7 50 30 April 6 213 70.1 53.0 290 7 50
Xenus cinereus 28 April 0 6 116 48 .1 28.6 54.5 6 50 28 April 0 6 113 44.3 27.7 78 4 50 29 April 0 6 114 49.8 29.4 85 6 50
127 Waders and other waterbirds in the United Arab Emirates
APPENDIX 9. Itinerary autumn 1994 & spring 1995.
24 September. Departure from Schiphol, via Amman, to Abu Dhabi. 25 September. Arrival at night; meeting Erik Hirschfeld at the airport. In the morning Erik shows us Abu Dhabi; in the afternoon birding at Al Wathbah Camel Race Course. 26 September. No car available yet, so: birdwatching in Abu Dhabi. 27 September. Meeting with part of the NARC·staff (Dick Hornby and Peter King) and receiving a letter of recommendation (in arabic), needed to get the driving license. Getting driving licence at traffic police. In the evening meeting with the Polish wader catchers and taking over the Toyota Landcruiser from them. 28 September. To Khor Dubai. Trying to reach the coast between Abu Dhabi and Dubai. Counting of Broad-billed Sandpipers at Khor Dubai with Colin Richardson. Sleeping rough near MushrifNational Park. 29 September. In the morning bird count at Khor Dubai. In the afternoon sampling of macrozoobenthos at a small pool near the police post, southern part of Khor Dubai. In the evening returning to Abu Dhabi. 30 September. In the morning birding at Al Wathbah Camel Race Course. In the afternoon Erik shows us Ad Dab'iyyah. 1 October. Counting of birds at Ad Dab'iyyah, taking macrozoobenthos samples at the northwestern side. In the evening meeting with Simon Aspinall at the NARC apartment. 2 October. In the morning shopping, changing money, etc. Then to HaJat lamilah, counting Broad billed Sandpipers (and other waders). Then driving to lebel Dhanna (just west of Ruwais), where sleeping rough. 3 October. In the morning counting of waders at the western side of lebel Dhanna, observations of feeding Broad-billed Sandpipers and sampling of macrozoobenthos. Driving back to Abu Dhabi, meanwhile trying to reach the northern coastline. Counting waders at Shaksa'eet al Ya'en. 4 October. Sorting of macrozoobenthos sample at NARC apartment. 5 October. To Umm al Quwain; counting at eastern shore. Then to Ras al Khaimah, where khor al Khaimah was examined. 6 October. Meeting with loe Platt at Dubai. Then visit of Khor Dubai and counting of Broad- billed Sandpipers. Taking benthic samples. 7 October. To Khor al Khowair and AI lazirah al Hamra, counting waders. To the east coast in the late afternoon. Sorting of macrozoobenthos (of Khor Dubai) in the mountains southeast of Habab. 8 October. Birding at Fujairah National Dairy Farm and near Dibba. 9 October. Looking for Broad-billed Sandpipers at wetlands along the coast at Khor Kalba and Khor Fakkan. 10 October. Birdwatching at the Emirates Golf Course. Meeting with Erik Hirschfeld. 11 October. Bringing equipment to Simon Aspinall at Sweihan (NARC office). 12 October. To airport at 04.00 hrs. Via Amman to Schiphol airport.
128 Waders and other waterbirds in the United Arab Emirates
6 April. Arrival at Abu Dhabi airport of Tom, Ruurd and Paul with Garuda Airways and welcomed by Simon with visas. Car rented in Abu Dhabi and travelled to NARC field station in Ras Ghanada. 7 April. Birdwatching Emirates Golf Course. First visit to Khor Dubai. 8 April. Birdwatching at Saffa Park. Meeting with police guards and loe Platt at Khor Dubai. Exploration of mudflats. First observation of foraging Broad-billed Sandpipers. 9 April. Birdwatching at Wathba Camel Race Course on the way to Abu Dhabi. Visit to NARC office in Abu Dhabi. Spoken to Dick Hornby. A fax was send to Guido. 10 April. Count of Ras Ghanada early in the morning. Samples taken at Khor Dubai. Several encounters with police guards of the nature reserve. loe Platt cleared up matters with police. 11 April. Macrozoobenthos sampling and wader catching in Khor Dubai. 12 April. First count of waterbirds in Khor Dubai. Wader catching at night in Khor Dubai. 13 April. Count of Ras Ghanada. Feeding observations in Khor Dubai of Broad-billed Sandpipers. Samples taken at Ras Ghanada. 14 April. Bird survey of garden Jebel Ali Hotel. Feeding observations of Broad-billed Sandpipers in Khor Dubai. Samples taken for vertical distribution of macrozoobenthos. Meeting with Marijcke Jongbloed of the Arabian Leopard Trust. 15 April. Wader count and macrozoobenthos sampling at Ras Al Khaimah. Visit to Umm al Quwain. 16 April. Visit to NARC office in Abu Dhabi. Meeting with Simon. Counting and sampling at Abu al Abyadh/Dhabbiyah (Abu Dhabi). 17 April. Wader count and macrozoobenthos sampling in Khor AI Beidah (Umm al Quwain). Birdwatching at the Emirates Golf Course in the morning. 18 April. Waterbird count of Khor Dubai and feeding observations of Broad-billed Sandpipers. 19 April. Feeding observations of Broad-billed Sandpipers and sampling of faeces at Khor Dubai. Bird survey of Emirates Golf Course in the early morning. 20 April. Feeding observations of Broad-billed Sandpipers and Nereis sampling in Khor Dubai. Sampling faeces of Broad-billed Sandpipers en Lesser Sandplover. Visit to Dubai Museum. 21 April. Count of Ras Ghanada. Count of Broad-billed Sandpipers in Khor Dubai. 22 April. Visit to NARC office in Abu Dhabi, birdwatching in Bateen Wood. To Jebel Dhanna where sleeping rough. 23 April. Strong wind during night at Jebel Dhanna. Wader count and macrozoobenthos sampling in Jebel Dhanna. Bird survey of AI Wathba Camel Race track. 24 April. Count ofKhor Dubai failed due to rain and strong wind. Feeding observations of Broad billed Sandpipers in Khor Dubai. Meeting with Colin Richardson. 25 April. Successful count ofKhor Dubai. 26 April. Visit to NARC office in Abu Dhabi, meeting with Simon Aspinall. Second car rented. Meeting with Jeroen Steeghs at Dutch Embassy. Picking up second group at Dubai Airport (expected arrival 21 :30). 27 April. Arrival of Bram, Eric and Guido at 0 I :40 at Dubai Airport. Introducing second group to Khor Dubai and Wafi shopping mall. Visit to Marijcke Jongbloed and celebration of Dutch queen's birthday in Hilton Beach Club ('Oranjebal'). 28 April. Wader count and macrozoobenthos sampling in Khor Dubai. Feeding observations of Broad- billed Sandpipers in Khor Dubai. Wader catching by Guido and Eric in Khor Dubai. 29 April. Discussing programme with entire team. Visit to AI Suq, Dubai. Wader catching in Khor Dubai. The first two Broad-billed Sandpipers art' caught near the tape recorder! Guido saw a small crocodile. 30 April. Simon, Tom, Ruurd and Paul visit Khor Kalba (Fujaira) for counting and catching White-Collared Kingfishers. The catching sessions in the evening turned into a 'midge nightmare'. Guido and Eric catch waders in Khor Dubai.
129 Waders and other waterbirds in the United Arab Emirates
1 May. Second part of kingfisher census and ringing and sampling macrozoobenthos at Khor Kalba. Sleeping rough by Tom, Ruurd and Paul near the small reservoir of the Ziqt Dam turned into a 'mosquito nightmare'. Guido and Eric catch waders and observe departures of waders in Khor Dubai. 2 May. Paul almost kidnapped at gunpoint by hill tribesman near Ziqt Dam but remained cool. Large wader count in Khor Dubai. Guido and Eric catch waders and observe departures in Khor Dubai. 3 May. Count of Ras Ghanada by Bram, Guido and Eric. Wader catching and departure observations in Khor Dubai. Departure Tom, Ruurd and Paul from Dubai Airport. 4 May. Meeting with Mr. John Ward, Head of Environmental Protection Dubai Municipality, Dubai. Sampling and counting. 5 May. Macrozoobentic sampling in Khor Dubai and scoring fecding activities (06.00-11.00). Taking away mistnets (11.00-12.30). Afternoon: homework and swimming. 6 May. Feeding protocols 07.00-12.00. Telephone calls, shopping. Visiting Colin Richardson. Counting Khor al Beidah (14.00-18.30). 7 May. Shopping, visiting Joe Platt, post office, lunch. 14.00-16.00 sampling Nereis. 16.00-18.00 counting Khor Dubai. 18.00-19.15 migration. 8 May. To Khor Kalba. 9 May. Via Dibba back home. 10 May. Birding Golf Course. Failed shopping and failed visit to City Council due to Eid holidays. Sampling faeces of Lesser Golden Plovers. Sorting Nereis samples. Afternoon: counting Ras Ghanada, computerizing data. Visit to Abu Dhabi. 11 May. Counting water birds at Khor Dubai 07.00-09.30 hrs. Sampling faeces of Curlew Sandpiper, Grey Plover and Mongolian Plover afterwards. Shopping and photocopying. Visiting Marijcke Jongbloed (not at home) and Dubai Zoo. Back home: washing mist nets, swimming and fishing in afternoon. Making plans for last day. Computerizing data. 12 May. Washing mistnets and swimming. Packing and cleaning apartment, leaving at 16.30 to Abu Dhabi, where meeting Simon. Eating and discussing last things concerning project. Simon bringing us to airport, where leaving to Paris at 00.50. 13 May. Back home after trip of26 hours.
130 Waders and other waterbirds in the United Arab Emirates
List of WIWO-reports. The WIWO-report series intends to be a regular medium by which occasional reports of ornithological expeditions or journeys can be published. In this way regular distribution and availability are guaranteed.
1. Altenburg W., M. Engelmoer, R. Mes & T. Piersma 1982. Wintering waders at the Banc d'Arguin, Mauritania. Comm. 6 Wadden Sea Working Group. Leiden, The Netherlands. Sold out. 2. Kersten M., T. Piersma, C. Smit & P. Zegers 1983. Wader migration along the Atlantic coast of Morocco, March 1981 . Texel, The Netherlands. f 25,- 3. Philippona J. 1985. Waterbirds at some wetJands in Turkey and Greece. Zeist, The Netherlands. f 4,- 4. Bijlsma R.G. & F.E. de Roder 1985. Waders along the coast of Thailand during November and December 1984. Zeist, The Netherlands. f 10,- 5. De Roder F.E. 1985 . Waterbirds on some Turkish wetlands, OctoberlNovember 1983. Zeist, The Netherlands. f 8,- 6. Van den Berk V., R.G . Bijlsma & F.E. de Roder 1985 . The importance of some wetlands in Turkey for transient and wintering birds in Turkey. Zeist, The Netherlands. f 10,- 7. Piersma T. 1985. Wader studies and waterbirds in the Nakdong Estuary, South Korea, in September 1984. Zeist, The Netherlands. f 12,50 8. Chalabi B., J. Harrison & G. van Dijk 1985. Les zones humides du Nord-Est Algerien en 1984. Zeist, The Netherlands. f 10,- 9. Ens B. 1985. Tussen Sahara en Siberie. Ewijk, The Netherlands. f 5,- 9. Ens B. 1985 . Entre Sahara et Siberie. Ewijk, The Netherlands. Sold out. 10. Van den Berk V., D. van Dorp, O. van Hoom & R. Vos 1986. Cranes and waterfowl counts of some Turkish wetlands. Zeist, The Netherlands. f 7,50 11. Van Dijk A.J., K. van Dijk, L. Dijksen, T. van Spanje & E. Wymenga 1986. Wintering waders and waterfowl in the Gulf of Gabes, Tunisia, January-March 1984. Zeist, The Netherlands. f 30,- 12. Bijlsma R.G. & F.E. de Roder 1986. Notes on the birds of some wetlands in Turkey. Zeist, The Netherlands. f 7,50 13. Dijksen LJ. & FJ. Koning 1986. Mid-winter waterfowl census, Turkey 1986. Zeist, The Nether lands. f 10,- 14. Schilperoord L. & M. Schilperoord-Huisman 1986. Observations of waterbirds in some wetlands in Turkey, July/August 1986. Zeist, The Netherlands. f 7,50 15 . Altenburg W. 1987. Waterfowl in West African coastal wet1ands: a summary of current knowledge. Zeist, The Netherlands. f 10,- 16. Bennet C.A., R.G. Bijlsma & R. Stouthamer 1982. Survey of water birds on Egyptian wetlands, autumn 1981. Zeist, The Netherlands. Sold out. 17. Schekkerman H. & J.CJ. van Wetten 1987. An ornithological winter survey of Lake Turkana, Kenya. Zeist, The Netherlands. f 7,50 18 . Dijksen L.J. & P. van der Wolf 1987. Mid-winter waterfowl census Turkey January 1987. Zeist, The Netherlands. f 7,50 19. Lensink R. 1987. Notes on the birds of some wetlands in North-East Greece and Turkey. Zeist, The Netherlands. f 7,50 20. Meininger P.L. (ed.) 1990. Birds of the wetlands in North-East Greece, spring 1987. Zeist, The Netherlands. f 30,- 21. Dijksen L.J. & A-M.C. Blomert 1988. Mid-winter waterfowl census Turkey, January 1988. Zeist, The Netherlands. Sold out.
131 WIWO reports
22. Van der Have T., V.M. van den Berk, 1.P. Cronau & M.1. Langeveld (eds.) 1988. South Turkey Project. A survey of waders and waterfowl in the Cukurova deltas, spring 1987. Zeist, The Netherlands. Sold out. 23. Altenburg W. & J. van der Kamp 1989. Etude ornithologique preliminaire de la zone c6tiere du nord-ouest de la Guinee. Joint report ofWIWO and ICBP. WIWO-report 23 and ICBP study report 30, Zeist, The Netherlands and Cambridge, England. Sold out. 24. Chalabi B. & G. van Dijk 1988. Les zones hum ides dans la region de Anaba et El Kala en Mai 1987. Zeist, The Netherlands. f 7,50 25. Ens B.1., T. Piersma, W.J. Wo1ff, L. Zwarts (eds.) 1989. Report of the Dutch-Mauritanian project Banc d'Arguin 85/86. Joint report ofWIWO and RIN nr. 25, Zeist, The Netherlands. f 30,- 26. Altenburg W., E. Wymenga & L. Zwarts 1992. Ornithological importance of the coastal wetlands of Guinea-Bissau. Zeist, The Netherlands. Sold out. 27. Ens B.1., T. Piersma, WJ. Wolff & L. Zwarts 1990. Homeward bound: Problems waders face when migrating from the Banc d'Arguin, Mauritania, to their northern breeding grounds in spring. WIWO/RIN, ZeistlTexel. f 55,- 28. Van Winden A., K. Mostert, P. Ruiters, M. SIlCl & H. de Waard 1989. Waders and waterfowl in spring 1988 at Eber GoIU. Zeist, The Netherlands. f 10,- 29. Van den Berg A.B. 1988. Moroccan Slender-billed Curlew survey, winter 1987-88. Joint report of WIWO and ICBP nr. 29, Zeist, The Netherlands and Cambridge, England. Sold out. 30. keijl G.O., M.WJ. van Roomen, P.S. Ruiters & A. Wijker 1992. Migration of waders and other waterbirds along the Mediterranean coast of Israel, spring 1989. Zeist, The Netherlands. f 20,- 31. Dijksen LJ. & A-M. Blomert 1989. Mid-winter waterfowl census Turkey January 1989. Zeist, The Netherlands. f 10,- 32. Schekkerman H. & M.W.1. van Roomen (eds.) 1993. Migration of water birds through wetlands in Central Anatolia, spring 1988. Zeist, The Netherlands. f 15,- 33. Spiekman H. & N. Groen 1993. Survey of breeding waders and relations between breeding performance and lemming densities, North-East Taimyr, Siberia, 1992. Zeist, The Netherlands. f 15,- 34. Van den Berk V.M., lP. Cronau & T.M. van der Have 1993. Waterbirds in the Van Province, eastern Turkey, May 1989. Zeist, The Netherlands. f 15,- 35. Altenburg W. & 1. van der Kamp 1991. Ornithological importance of coastal wetlands in Guinea. Joint report ofWIWO and ICBP. WIWO-report 35 and ICBP study report nr. 47, Zeist, The Nether lands and Cambridge, England. f 10,- 36. Van der Have T.M., S. van der Sant, Y. Verkuil & 1. van der Winden (eds.) 1994. Waterbirds in the Sivash, Ukraine, spring 1992. Zeist, The Netherlands. f 20,- 37. Dijksen L.J. & A-M. Blomert 1993. Mid-winter waterfowl census Turkey January 1990. Zeist, The Netherlands. f 15,- 38. Spiekman H.W., G.O. Keijl & P.S. Ruiters (eds.) 1993. Waterbirds in the Kneiss area and other wet lands, Tunisia. Eastern Mediterranean Wader Project, spring 1990. Zeist, The Netherlands. f 25,- 39. Wo1ff W.J. (ed.) 1998. Waders in Guinea-Blssau, October 1992-May 1993. The end of the East Atlantic Flyway. f 25,- 40. Meininger P.L. & G.A.M. Atta (eds.) 1994. Ornithological studics in Egyptian wetlands 1989/90. FORE-report 94.0 I, Zeist, The Netherlands. f 35,- 41. Schepcrs F.J. & E.C.L. Marteijn (eds.) 1993. Coastal waterbirds in Gabon. Zeist, The Netherlands. f 30,- 42. Hirschfeld E., S.A. Mohamed & T. Stawarczyk 1992. Bahrain wader study 1991. Zcist, The Netherlands. f 10,- 43. Brehme S., T. MUller & J. Redlich 1992. Bird observations in the Danube delta and in the Dobrodgea (Romania). Zcist, The Netherlands. f 10,- 44. Spiekrnan H. 1992. Wader ringing in Tunisia 1962-1986. Zeist, The Netherlands. f 10,-
132 Waders and other waterbirds in the United Arab Emirates
45. Hustings F. (ed.) 1994. Bird census in the KIl.llmnak delta, Turkey, in 1992. Zeist, The Netherlands. f 25,- 46. Meininger P.L., P.A. Wolf, D.A. Hadoud & M.F.A. Essghaier 1994. Ornithological survey of the coast of Libya, July 1993. Zeist, The Netherlands. f 15,- 47. Groen N.M. & PJ. Zomerdijk (eds.) 1994. Waders and waterbirds along part of the Atlantic coast of Morocco, autumn 1991 - spring 1992. Zeist, The Netherlands. f 20,- 48. Kivit HA, H. Nijmeijer & A. Ovaa (eds.) 1994. Wader and waterfowl migration in the <;:ukurova deltas, South Turkey, spring 1990. Zeist, The Netherlands. f 25,- 49. Hagemeijer W.l.M. (ed.) 1994. Wintering waterbirds in the coastal wetlands of Albania, 1993. Zeist, The Netherlands. f 20,- 50. Dijksen L.J. & M.C.M. Klemann 1994. Wintering geese in Turkey, January 1992. Zeist, The Netherlands. f 15,- 51. Gerritsen G.J. & N.M. Groen 1995. Icelandic Black-tailed Godwit project 1993. Zeist, The Netherlands. f 15,- 53. De Nobel W.T. (ed.) 1995. Birds of the Messolonghi wetlands. Eastern Mediterranean Wader Project, spring 1990. Zeist, The Netherlands. f 25,- 54. Van der Have T.M., N. Bacetti, G.O. Keijl & M. Zenatello 1997. Waterbirds in Kneiss, Tunisia, February-March 1994. Zeist, The Netherlands. f 25,- 55. Schekkerman H. & M. Van Roomen 1995. Breeding waders at Prochishcheva Lake, Northeastern Taimyr, Siberia, in 1991. Zeist, The Netherlands. f 20,- 56. Van den Brink B., R.G. Bijlsma & T.M. van der Have (eds.) 1998. European Swallows Hirundo rustica in Botswana. Zeist, The Netherlands. f 20,- 57. Tulp 1., L.W. Bruinzee1, 1. lukema & O. Stepanova 1997. Breeding waders at Medusa Bay, western Taimyr, in 1996. Zeist, The Netherlands. f 20,- 58. Van den Brink B., R.G. Bijlsma & T.M. van der Have (eds.) 1998. European songbirds and Barn Swallows Hirundo rustica in Ghana: a quest for Constant Effort Sites and swallow roosts in December/January 1996/97. Zeist, The Netherlands. f 15,- 59. Veerman T. & H. Wessels 1998. Cranes Grus grus in NW-Russia, autumn 1996. Zeist, The Netherlands. f 10,- 60. Willems FJ. & E. de Vries 1998. Ecological aspects of Pygmy Cormorants Phalacrocorax pygmeus in Prespa, Greece, May-August 1996. Zeist. The Netherlands. f 25,- 61. Tulp I., H. Schekkerman, T. Piersma, 1. Jukema, P. de Goeij & 1. van de Kam 1998. Breeding waders at Cape Sterlegova, northern Taimyr, in 1994. Zeist, The Netherlands. f 25,- 62. Keijl G.O., P.S. Ruiters, T.M. van der Have, A. bij de Vaate, E.C.L. Marteijn & R. Noordhuis 1998. Waders and other waterbirds in the United Arab Emirates, autumn 1994 and spring 1995. Zeist, The Netherlands. f 25,- 63. Schepers FJ., G.O. Keijl, P.L. Meininger & l8. Rigolot 1998. Oiseaux d'eau dans le Delta du Sine Saloum et la Petite Cote, Senegal, janvier 1997. WIWO, Zeist, The Netherlands & Direction Parcs Nationaux du Senegal, Dakar, Senegal. f 25,-
These reports can be ordered by paying the mentioned amounts for each required copy, vlus f JS. administration costs for each separate order of WIWO-reports, to postal giro account 2.666.009 or to ABN bank account 57.02.16.613 of Stichting wrwo, van Stuivenbergweg 4, 6644 AB Ewijk, The Netherlands. It is important to mention the numhers of the required reports. Postage for surface mail is included in the prices. The administration costs are required to cover the bank costs for payments from abroad. They are not due for payments from Dutch accounts, for payments by Eurocheque, provided that {he bank vassnumber is filled in on the reverse side, or for cash payments.
133
WIWO Foundation Working Group for International Waterbird and Wetland Research
WIWO, a fmmdation under Dutch law, was established in 1983 to form a unifying c~ntre for Dutch ornithologists participating in ornithological expeditions to West-Africa. The aims of WIWO are to initiate, stimulate and organise scientific research on waterbirds and wetlands worldwide and to transfer the gathered knowledge for the protection of the habitats and bird popuIations involved. WIWO is an organisation exclusively working with unpaid volunteers with a miscellaneous scientific background. The data collected in the field during WIWO-projects often require laborious efforts at home to evaluate, analyse and report them. Up to J998 over 60 projects have been carried out in J 8 different countries.
During the expeditions much information has been collected on waterbirds in a large number ofwetlands along the entire East Atlantic Flyway, along the Mediterranean Flyway, and in the Eurasian Arctic. Furthermore, information has been collected on function, importance and extent of protection and threats to the wetlands visited. WIWO's main role is to gather information that will provide a sound basis for the protection of the populations and areas concerned. The results are made available to all organisations and individuals active in nature conservation through a series of reports, as well as through scientific: and popular papers. Up to 1998 over 60 reports have been published. WlWO does not act as co-ordinating organisation such as Birdlife International or IUCN. The main strength of WIWO is its capability to mobilize volunteers with a professional attitude for ornithological research expeditions.
All correspondence should be sent to WIWO, P.O. Box 925, 3700 AX Zcist, The Netherlands. WADERS AND OTHER WATERBIRDS IN THE UNITED ARAB EMIRATES autumn 1994 & spring 1995
In autumn 1994, winter 1994-1995 and spring 1995 coastal wetlands in the United Arab Emirates were surveyed for waders and other waterbirds. Special attention was paid to waders in Khor Dubai, a shallow lagoon near Dubai city. In this area, about 4,000 waders were counted in autumn and spring, and about 12,000 in winter. Up to 100,000 waders can be present in the UAE at a single moment during migration, Kentish and Lesser Sandplover, Dunlin and Bar tailed Godwit being the most numerous wader species. The UAE holds internationally important numbers of Socotra Cormorants, Grey Heron, Western Reef Egret, most wader species, Sooty Gull and several tern species for most of the year. Numbers of Broad-billed Sandpipers were found to be very low compared to numbers counted in Khor Dubai during the mid-1980's. In this report data are presented on migration, biometry, and on food intake of waders feeding on ragworms.
WIWO-report 62
1998