Population Status and Conservation Targets for Globally Threatened Migratory Land Birds
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Population status and conservation targets for globally threatened migratory land birds Returns to Nature FOR: 1. Scientific Council of the Convention on the Conservation of Migratory Species of Wild Animals 2. Migratory Landbird Study Group of the African-Eurasian Migratory Landbirds Action Plan (AEMLAP). BY: Rael Matthew Loon © Returns to Nature, [email protected] CONTENTS: PREAMBLE SPECIES ACCOUNTS: 1 Northern Bald Ibis Geronticus eremita 2 Bengal Florican Houbaropsis bengalensis 3 Lesser Florican Sypheotides indica 4 Spotted Ground Thrush Zoothera guttata 5 Yellow-breasted Bunting Emberiza aureola 6 Basara Reed Warbler Acrocephalus griseldis 7 Southern Bald Ibis Geronticus calvus 8 Great Bustard Otis tarda 9 Blue Swallow Hirundo atrocaerulea 10 Pale-backed Pigeon Columba eversmanni 11 Marsh grassbird Megalurus pryeri 12 Bristled Grasssbird Chaetornis striatus 13 Grey Sided Thrush Turdus feae 14 Machurian Reed-warbler Acrocephalus tangorum 15 Aquatic Warbler Acrocephalus paludicola 16 Kashmir Flycatcher Ficedula subrubra 17 Dark-rumped Swift Apus acuticauda 18 Styan’s Grasshopper Warbler Locustella pleskei 19 White-throated Bush Chat Saxicola insignis 20. Denham’s Bustard Neotis denhami 21. Houbara Bustard Chamydotis undulate 22. Little Bustard Tetrax tetrax 23. Syrian Serin Serinus syriacus 24. Buff-breasted Sandpiper Tryngites aubruficollis 25. Tytler’s Leaf Warbler Phylloscopus tytleri 26. Japanese Waxwing Bombycilla japonica 27. Japanese Quail Coturnix japonica 28. Ochre-rumped Bunting Emberiza yessoensis 29. Cinereous Bunting Emberiza cineracea 30. Firethroat Luscinia pectardens 31. Derbyan Parakeet Psittacula derbiana 32. European Roller Coracias garrulus PROPOSED GENERAL ACTIONS GOING FORWARD REFERENCES Returns to Nature PRE-AMBLE During CMS COP 10 an Action Plan for Migratory Landbirds in the African Landbirds in the African Eurasian Region (UNEP/CMS) was drafted (Resolution 10.27). This Action Plan was updated by the recently formed African-Eurasian Migratory Landbirds Working Group under the auspices of the CMS Scientific Council earlier this year (2014). One of the products of this process was a document entitled “Improving the Conservation Status of Migratory Landbird Species in the African-Eurasian Region” (UNEP/CMS/ScC18/Doc. 10.7.1.) Various actions were accordingly requested of the Scientific Council, specifically the council was invited to : (1) Review and endorse the Action Plan for Migratory Landbirds in the African-Eurasian Region, including its annexes, and to agree on its submission to COP11 for discussion and adaption, (2) Provide advice on scientific and technical issues pertaining to the conservation of African Eurasian Migratory Landbirds and recommed priority researtch to fill existing gaps. This report is drafted in the above context and aims to contribute to the AEMLAP by focusing on the globally threated and near threatened species (as per Category A of Annex 3). It is also aimed at hopefully complementing this Action Plan by focusing on the research and monitoring guidelines as per Doc. 10.7.1 (pages 18-20). These include and pertain to (1) Understanding migration patterns and connectivity along flyways; (2) Monitoring of population trends; (3) Understanding causes of population change in migratory land bird species; and (4) Building capacity and improve the exchange of information, collaboration and coordination between researchers studying migratory land bird species. This document thus presents a broad summary globally threatened and near threatened bird species. Species are catalogued according to their respective IUCN Red List status (from Critically Endangered to Near Threatened). As a broad overview it is hoped that this approach may complement the work of the CMS Scientific Council and AEMLAP, while recognizing that many issues would need to be explored in greater detail. The focus in the African Eurasian flyway, as defined by the AEMLAP report. However it should be noted that there is a fair amount of overlap with the East Asian-Australasian flyway (for example Pale-backed Pigeon, Bengal and Lesser Florican, Great Bustard, Little Bustard, Marsh Grassbird, Grey-sided Thrush, White-throated Bush Chat, Derbyan Parakeet etc). It is hoped that this framework could complement the objectives of the CMS in general and within the context of COP11 and the Strategic Plan 2015-2023 in particular. As a follow-up to this report it is suggested that a similar exercize be conducted with regards to species listed in Category B (according to UNEP/CMS/ScC18/Doc. 10.7.1.) with decreasing global population trends, and that these reports complement existing efforts and form the basis of a database on these species going forward. An appropriate conduit for this would be via BirdLife International’s Migratory Bird Flyways Programme and it’s associated species information database (see http://www.birdlife.org/datazone/species). Returns to Nature 1. Northern Bald Ibis Geronticus eremita (Critically Endangered) MIGRATION PATTERNS AND CONNECTIVITY ALONG PATHWAYS This species only occurs in viable numbers in Morocco, specifically the Souss-Massa National Park & Tamri, a total range of only some 580 square kilometres. It is thought that birds used to winter in Yemen, Saudia Arabia, Eritrea and Sudan. It also used to occur in Turkey, but is critically endangered and possibly even extinct there. MONITORING POPULATION TRENDS In Souss-Massa National Park and Tamri, Morocco, 113 pairs (i.e. 226 mature individuals) nested, out of 319 adults in 2013, and produced 148 fledged young. In 2011, at least 100 pairs produced at least 130 fledged young, matching the breeding success of 2010, when 105 pairs fledged 138 young. After the breeding season the total number of birds in the western population may have exceeded 500 in 2011- 2012, but most recently has been evaluated as 443 individuals. Only a single mature female returned to Syria in 2013, and 2011 was the last successful breeding when a single breeding pair fledged two young. The Turkish population now numbers around 100 individuals, but these managed birds are excluded from the total estimate (BirdLife International 2014; Smith et al 2000). CAUSES OF POPULATION CHANGE Combination of factors, especially disturbance and persecution by man from hunting and also the loss of habitat, poisoning from pesticides and the construction of dams. CONSERVATION TARGETS/ RESEARCH PRIORITIES: (1): Conduct research into their habitat requirements and feeding and breeding biology (Bowden et al 2003); (2) monitor numbers and breeding success; (3) try to prevent disturbance and development near their key breeding and roosting sites; (4) establish their ecological requirements and use this information to try to reintroduce captive-bred birds into previously occupied sites (Brindley et al 1995). Returns to Nature 2. Bengal Florican Houbaropsis bengalensis (Endangered) MIGRATION PATTERNS AND CONNECTIVITY ALONG PATHWAYS There are two disjointed populations. The first is in Indian subcontinent, where it occurs in fragmented subpopulations in the region of Uttar Pradesh, Assam and Arrunachal in India as well as an isolated subpopulation in the terai of Nepal. It formally occurred in Bangladesh but is thought extinct there. The other population is in South-East Asia where it occurs in Cambodia and adjacent southern Vietnam (BirdLife International 2000). MONITORING POPULATION TRENDS The population of this species is decreasing and it is classified as endangered. The population in Cambodia was estimated at 294 displaying males or c.600 individuals in 2009, but recently an extensive survey has reported a total of only 432 individuals (95% CI 312-550). 75-96 individuals remain in Nepal. No recent estimates are known from India but the total global population for this species is likely to fall in the range 250-999 mature individuals. This equates to 375-1,499 individuals in total, rounded here to 350-1,500 individuals (BirdLife International 2014). CAUSES OF POPULATION CHANGE The primary cause of the decrease in numbers is the significant loss and modification of its grassland habitat through the conversion to agriculture, drainage, overgrazing, over cutting, inappropriate burning regimes, flooding, hunting, human disturbance and the trampling of nests by livestock (BirdLife International 2000). CONSERVATION TARGETS/ RESEARCH PRIORITIES: (1): Conduct surveys for populations, especially in Cambodia; (2) monitor current populations; (3) expand and connect existing protected areas and establish new ones; (3) promote and implement rotational burning, grazing and cutting regimes in protected areas; (4) control human disturbance and hunting; (5) facilitate the regeneration of grassland habitats; (5) promote awareness campaigns about grassland conservation; (6) integrate these efforts with existing strategies to conserve bustards in India. Returns to Nature 3. Lesser Florican Sypheotides indica (Endangered) MIGRATION PATTERNS AND CONNECTIVITY ALONG PATHWAYS This species breeds in several isolated sub-populations in India and disperses within India in the non- breeding season. It has also been recorded in Pakistan and is a summer migrant to Nepal. MONITORING POPULATION TRENDS Formally far more common, the Lesser Florican has declined in numbers throughout its range. By 1994 its numbers were estimated at around 2200 birds. It is now classified by the IUCN Red List as Endangered (BirdLife International 2000). CAUSES OF POPULATION CHANGE Pressure from hunting