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A global threats overview for Numeniini populations: synthesising expert knowledge for a group of declining migratory birds
- JAMES W. PEARCE-HIGGINS, DANIEL J. BROWN, DAVID J. T. DOUGLAS, JOSÉ A. ALVES, MARIAGRAZIA BELLIO, PIERRICK BOCHER, GRAEME M. BUCHANAN, ROB P. CLAY, JESSE CONKLIN, NICOLA CROCKFORD, PETER DANN, JAANUS ELTS, CHRISTIAN FRIIS, RICHARD A. FULLER, JENNIFER A. GILL, KEN GOSBELL, JAMES A. JOHNSON, ROCIO MARQUEZ-FERRANDO, JOSE A. MASERO, DAVID S. MELVILLE, SPIKE MILLINGTON, CLIVE MINTON, TAEJ MUNDKUR, ERICA NOL, HANNES PEHLAK, THEUNIS PIERSMA, FRÉDÉRIC ROBIN, DANNY I. ROGERS, DANIEL R. RUTHRAUFF, NATHAN R. SENNER, JUNID N. SHAH, ROB D. SHELDON, SERGEJ A. SOLOVIEV, PAVEL S. TOMKOVICH, YVONNE I. VERKUIL
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- Journal:
- Bird Conservation International / Volume 27 / Issue 1 / March 2017
- Published online by Cambridge University Press:
- 01 March 2017, pp. 6-34
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The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
Contributors
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- By Ghazi Al-Rawas, Vazken Andréassian, Tianqi Ao, Stacey A. Archfield, Berit Arheimer, András Bárdossy, Trent Biggs, Günter Blöschl, Theresa Blume, Marco Borga, Helge Bormann, Gianluca Botter, Tom Brown, Donald H. Burn, Sean K. Carey, Attilio Castellarin, Francis Chiew, François Colin, Paulin Coulibaly, Armand Crabit, Barry Croke, Siegfried Demuth, Qingyun Duan, Giuliano Di Baldassarre, Thomas Dunne, Ying Fan, Xing Fang, Boris Gartsman, Alexander Gelfan, Mikhail Georgievski, Nick van de Giesen, David C. Goodrich, Hoshin V. Gupta, Khaled Haddad, David M. Hannah, H. A. P. Hapuarachchi, Hege Hisdal, Kamila Hlavčová, Markus Hrachowitz, Denis A. Hughes, Günter Humer, Ruud Hurkmans, Vito Iacobellis, Elena Ilyichyova, Hiroshi Ishidaira, Graham Jewitt, Shaofeng Jia, Jeffrey R. Kennedy, Anthony S. Kiem, Robert Kirnbauer, Thomas R. Kjeldsen, Jürgen Komma, Leonid M. Korytny, Charles N. Kroll, George Kuczera, Gregor Laaha, Henny A. J. van Lanen, Hjalmar Laudon, Jens Liebe, Shijun Lin, Göran Lindström, Suxia Liu, Jun Magome, Danny G. Marks, Dominic Mazvimavi, Jeffrey J. McDonnell, Brian L. McGlynn, Kevin J. McGuire, Neil McIntyre, Thomas A. McMahon, Ralf Merz, Robert A. Metcalfe, Alberto Montanari, David Morris, Roger Moussa, Lakshman Nandagiri, Thomas Nester, Taha B. M. J. Ouarda, Ludovic Oudin, Juraj Parajka, Charles S. Pearson, Murray C. Peel, Charles Perrin, John W. Pomeroy, David A. Post, Ataur Rahman, Liliang Ren, Magdalena Rogger, Dan Rosbjerg, José Luis Salinas, Jos Samuel, Eric Sauquet, Hubert H. G. Savenije, Takahiro Sayama, John C. Schaake, Kevin Shook, Murugesu Sivapalan, Jon Olav Skøien, Chris Soulsby, Christopher Spence, R. ‘Sri’ Srikanthan, Tammo S. Steenhuis, Jan Szolgay, Yasuto Tachikawa, Kuniyoshi Takeuchi, Lena M. Tallaksen, Dörthe Tetzlaff, Sally E. Thompson, Elena Toth, Peter A. Troch, Remko Uijlenhoet, Carl L. Unkrich, Alberto Viglione, Neil R. Viney, Richard M. Vogel, Thorsten Wagener, M. Todd Walter, Guoqiang Wang, Markus Weiler, Rolf Weingartner, Erwin Weinmann, Hessel Winsemius, Ross A. Woods, Dawen Yang, Chihiro Yoshimura, Andy Young, Gordon Young, Erwin Zehe, Yongqiang Zhang, Maichun C. Zhou
- Edited by Günter Blöschl, Technische Universität Wien, Austria, Murugesu Sivapalan, University of Illinois, Urbana-Champaign, Thorsten Wagener, University of Bristol, Alberto Viglione, Technische Universität Wien, Austria, Hubert Savenije, Technische Universiteit Delft, The Netherlands
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- Book:
- Runoff Prediction in Ungauged Basins
- Published online:
- 05 April 2013
- Print publication:
- 18 April 2013, pp ix-xiv
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Catatonia in present day society
- Sally A. Morgan, Dietmar Hank, Danny Rogers
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- Journal:
- Advances in Psychiatric Treatment / Volume 14 / Issue 5 / September 2008
- Published online by Cambridge University Press:
- 02 January 2018, p. 400
- Print publication:
- September 2008
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Intake rates and the functional response in shorebirds (Charadriiformes) eating macro-invertebrates
- John D. Goss-Custard, Andrew D. West, Michael G. Yates, Richard W. G. Caldow, Richard A. Stillman, Louise Bardsley, Juan Castilla, Macarena Castro, Volker Dierschke, Sarah. E. A. Le. V. dit Durell, Goetz Eichhorn, Bruno J. Ens, Klaus-Michael Exo, P. U. Udayangani-Fernando, Peter N. Ferns, Philip A. R. Hockey, Jennifer A. Gill, Ian Johnstone, Bozena Kalejta-Summers, Jose A. Masero, Francisco Moreira, Rajarathina Velu Nagarajan, Ian P. F. Owens, Cristian Pacheco, Alejandro Perez-Hurtado, Danny Rogers, Gregor Scheiffarth, Humphrey Sitters, William J. Sutherland, Patrick Triplet, Dave H. Worrall1, Yuri Zharikov, Leo Zwarts, Richard A. Pettifor
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- Journal:
- Biological Reviews / Volume 81 / Issue 4 / November 2006
- Published online by Cambridge University Press:
- 24 July 2006, pp. 501-529
- Print publication:
- November 2006
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As field determinations take much effort, it would be useful to be able to predict easily the coefficients describing the functional response of free-living predators, the function relating food intake rate to the abundance of food organisms in the environment. As a means easily to parameterise an individual-based model of shorebird Charadriiformes populations, we attempted this for shorebirds eating macro-invertebrates. Intake rate is measured as the ash-free dry mass (AFDM) per second of active foraging; i.e. excluding time spent on digestive pauses and other activities, such as preening. The present and previous studies show that the general shape of the functional response in shorebirds eating approximately the same size of prey across the full range of prey density is a decelerating rise to a plateau, thus approximating the Holling type II (‘disc equation’) formulation. But field studies confirmed that the asymptote was not set by handling time, as assumed by the disc equation, because only about half the foraging time was spent in successfully or unsuccessfully attacking and handling prey, the rest being devoted to searching.
A review of 30 functional responses showed that intake rate in free-living shorebirds varied independently of prey density over a wide range, with the asymptote being reached at very low prey densities (<150/m−2). Accordingly, most of the many studies of shorebird intake rate have probably been conducted at or near the asymptote of the functional response, suggesting that equations that predict intake rate should also predict the asymptote.
A multivariate analysis of 468 ‘spot’ estimates of intake rates from 26 shorebirds identified ten variables, representing prey and shorebird characteristics, that accounted for 81% of the variance in logarithm-transformed intake rate. But four-variables accounted for almost as much (77.3%), these being bird size, prey size, whether the bird was an oystercatcher Haematopus ostralegus eating mussels Mytilus edulis, or breeding. The four variable equation under-predicted, on average, the observed 30 estimates of the asymptote by 11.6%, but this discrepancy was reduced to 0.2% when two suspect estimates from one early study in the 1960s were removed. The equation therefore predicted the observed asymptote very successfully in 93% of cases.
We conclude that the asymptote can be reliably predicted from just four easily measured variables. Indeed, if the birds are not breeding and are not oystercatchers eating mussels, reliable predictions can be obtained using just two variables, bird and prey sizes. A multivariate analysis of 23 estimates of the half-asymptote constant suggested they were smaller when prey were small but greater when the birds were large, especially in oystercatchers. The resulting equation could be used to predict the half-asymptote constant, but its predictive power has yet to be tested.
As well as predicting the asymptote of the functional response, the equations will enable research workers engaged in many areas of shorebird ecology and behaviour to estimate intake rate without the need for conventional time-consuming field studies, including species for which it has not yet proved possible to measure intake rate in the field.