Australasian Wader Studies Group Conference Phillip Island, Victoria
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The Stilt 35 (1999) Reports ABSTRACTS AUSTRALASIAN WADER STUDIES GROUP CONFERENCE PHILLIP ISLAND, VICTORIA. 12 TO 13™ JUNE 1999 Compiled by Rosalind Jessop1 and Peter Collins2 1RMB 4009, Cowes 3922 Vie. AUSTRALIA 2Phillip Island Nature Park, PO Box 97, Cowes 3922 Vie. AUSTRALIA Following the success of the first Australasian Wader Studies Group Conference in 1996 in Brisbane, Queensland, Australia, the second conference was held at Banfields Conference Centre, Cowes, Phillip Island, Victoria, Australia from the 12 to 13th June 1999. Over 70 delegates from Australia and New Zealand attended with participants from all states represented apart from South Australia and the Northern Territory. Abstracts of the twenty-seven papers and five posters dealing with a wide range of wader biology are given below. The organisers would like to take this opportunity to thank the committee members of the AWSG for their support and their presence during the conference. In particular Phil Straw and Jim Wilson for their numerous phone calls. The organisers also thank the Phillip Island Nature Park Board of Management for their assistance in providing access to e-mail and computer facilities, stationary and photocopying and numerous other aspects that helped to make the conference run smoothly. The Phillip Island Nature Park also sponsored visits by delegates and their families to the Penguin Parade, Koala Conservation Centre and Churchill Island. Finally we would like to thank all the people who attended the conference without whose support the conference would not have been as enjoyable or as worthwhile. MAPPING BUSH STONE-CURLEW HABITAT BREEDING BIOLOGY OF HOODED PLOVERS PREFERENCES AROUND TOWNSVILLE, ON PHILLIP ISLAND AND METHODS OF NORTH QUEENSLAND 1998-2000 INCREASING BREEDING SUCCESS Alexandra Appleman Bob Baird and Peter Dann James Cook University, Townsville 4811 Phillip Island Nature Park, P. 0. Box 97, Cowes, AUSTRALIA Phillip Island 3922 Vie. AUSTRALIA E-mail: [email protected] The breeding biology of Hooded Plovers Thinornis The non-migratory Bush Stone-curlew Burhinus rubricollis was studied on Phillip Island in Victoria grallarius, is present in reduced numbers across much between 1993-99. Breeding extended from August to of its former range. In coastal north Queensland it is March and usually peaked in December or January. A still relatively common and readily found close to total of 27 breeding sites on 17 beaches were used and urban areas. A Geographic Information System (GIS) the types of nesting site were flat beaches (43%), was used to establish the presence or absence of the stony terraces (33%) and ledges on eroding dunes bird across the urban landscape based upon 40 sites (24%). Forty-four percent of breeding attempts generated by a random number system. These sites occurred on only three of the beaches on the island. were categorized on land use and land management, The mean clutch size was 2.4 and hatching success vegetation cover, drainage patterns and disturbance was 17%. Predation by dogs and foxes, inundation by factors and compared to 40 sites where birds occurred. storm tides and trampling by sheep were the major Seasonal factors governing the movements of the causes of egg failure. Fledging success was 0.18 Bush Stone-curlew within and between suitable chicks per clutch and predation by dogs and foxes habitat are also monitored. This will help identify seemed the main cause of chick mortality. habitat preferences and generate base-line data on the local population. 59 The Stilt 35 (1999) Reports In 1995, we started an experiment to determine if in flight, but also decrease the mass carried aloft. For excluding predators and stock from nest sites would long trans-oceanic flights such organ savings may be improve hatching success and have a corresponding imperative. The implications of these findings for the effect on overall breeding success. We tested three latest models of fuel use in migrating birds will be types of exclosures and have developed what we discussed. believe to be an optimal design for excluding predators and stock as well as permitting access by the THE MOVEMENTS OF PIED birds. OYSTERCATCHERS FROM WINTERING Twenty exclosures have been deployed to date and SITES IN VICTORIA hatching success has been substantially increased as a Peter Collins1, Rosalind Jessop2 and Clive Minton3 result. So far overall breeding success has not been improved by the deployment of cages but the IRMB 4009, Cowes. 3922 Vie. AUSTRALIA combination of the cages, improved enforcement of 2Phillip Island Nature Park, PO Box 97, Cowes 3922 dog regulations and a dedicated team of volunteers has Vie. AUSTRALIA improved the plovers' breeding success substantially. 3t65 Dalgetty Road, Beaumaris Vie. AUSTRALIA 1&2E-mail: [email protected] DIFFERENTIAL ORGAN REDUCTION In order to understand the biology of Oystercatchers in DURING BIRD MIGRATION south eastern Australia Pied and Sooty Oystercatchers Phil F. Battleyl, Theunis Piersma2, Maurine W. have been individually colour banded since 1989 by Dietz3, Sixian Tang4, Anne Dekinga2 and Kees the Victorian Wader Study Group. Birds are caught at Hulsmanl traditional winter roosts using cannon-nets, banded with stainless steel bands supplied by the Australian I Australian School ofEnvironmental Studies, Bird and Bat Banding Schemes and colour banded Griffith University, Nathan Qld 4111. AUSTRALIA with spiral darvic rings. The first phase of the study is 2Netherlands Institute for Sea Research (NIOZ), looking at movements of individual birds. Individual P.O. Box 59, 1790 AB Den Burg, Texel, THE colour banding is an essential element of the study and NETHERLANDS allows the movements of different age classes from 3centre for Ecological and Evolutionary Studies, different winter roosting sites to be followed. Zoological Laboratory, University of Groningen, P.O. Box 14, 9750 AA Haren, THE NETHERLANDS In the past it has been assumed that individuals return 4Department of Biology, East China Normal to favoured wintering areas and that generally birds University, Shanghai 200062 CHINA are 'site faithful' to that area. It has also been assumed that Oystercatchers are not 'long distance The 'aircraft refuelling paradigm', stating that travellers'. This study shows that both these migratory birds build up and deplete only their fat assumptions are incorrect. With the help of stores before and during long-distance flights, individuals and bird club members, over 4000 remained largely uncontested from its proposal in resighting have been gathered and the preliminary 1964. Recent work has demonstrated substantial analysis of this data is presented. changes in organ sizes before departure, but only one study has attempted to determine whether organs are FEEDING ECOLOGY OF EASTERN CURLEW broken down during flight. IN WESTERN PORT BAY, VICTORIA To investigate changes in organ size and fat content in Peter Dann migratory birds, we studied Great Knots Calidris tenuirostris before and after a non-stop flight of 5,400 Phillip Island Nature Park, P. 0. Box 97, Cowes, km from north-west Australia to coastal China. On Phillip Island 3922 AUSTRALIA average, birds lost 85% of the stored fat. They also E-mail: [email protected] lost 16% of lean tissue mass, with significant decreases in pectoral muscles, skin, intestine, liver, Eastern Curlew are conspicuously sexually dimorphic kidneys, salt glands and the remainder of the carcass. in bill length and have the longest bills of all the All other organs except the brain showed the same curlew species. It has been speculated that the directional change. Reduction of functional functions of both these attributes are related to habitat components is reflected in a 46% decrease in basal and sexual selection on the breeding grounds or to metabolic rate. Organ reductions free nutrients for use mechanisms of resource partitioning on the non- 60 The Stilt 35 (1999) Reports breeding grounds. In this study, the foraging ecology to 1995/96 a total of 12 Hooded Plover juveniles of curlews was examined at Rhyll Inlet on Phillip survived to fledge. In the three breeding seasons from Island for three years. Their diet was determined from 1996/97 to 1998/99 a total of 31 juveniles survived to observations of feeding birds, regurgitated pellets and fledge, a 158% increase in breeding success. The adult prey remains. The curlews foraged largely on Hooded Plover population increased by 30% from an burrowing intertidal crabs and shrimps and showed average of 33 adult Hooded Plovers in the Park in the both territorial and non-territorial patterns of 1991/92 survey year, to an average of 43 adult dispersion while feeding. Territorial behaviour was Hooded Plover in the 1998/99 survey year. Colour related to habitat use and sex. Females were much banding of juveniles fledged from the Park identified a more territorial than males. Both bill length and bill number remained within the Park to breed in length dimorphism appeared to be related to feeding subsequent breeding seasons. habitats during the non-breeding period. Management introduced by Parks Victoria aimed to Prey selection and habitat preferences were examined decrease nest trampling and decrease disturbance by in relation to their profitability in terms of energy Park visitors in breeding areas. Management actions intake. The profitability of the frequented habitats included fencing walking tracks from car parks to the varied and curlews were found to be more territorial in beaches and closing informal tracks. A small number the more profitable ones. These preferred habitats of beaches with breeding Hooded Plovers have been were limited in size and prone to be rendered unusable temporarily closed to the public using signs and by environmental conditions. The foraging of curlews regular ranger patrols. Restricted access for dogs and appeared to be consistent with the theory that the net diligent enforcement of dog regulations by parks staff rate of energy intake was being maximised. have limited the influence of dogs on the birds.