Shorebird Research Group of the Americas

Welcome to the SRGA Website!

The Shorebird Research Group of the Americas (SRGA) was formed to help stimulate research on declining shorebird populations. Studies of shorebirds in North America have advanced our understanding of these remarkable birds. As reports of declining species mount, there has been a growing interest in research on what limits the populations of these species. Declines have been reported world-wide, but the reasons for the declines are largely unknown. Because studying these highly migratory birds requires work across the hemisphere, the Shorebird Research Group is helping to encourage collaborative projects and to form Working Groups focusing on limiting factors for shorebird species. We invite you to list yourself on our Bios page, to explore the links to existing groups or propose new working groups, and to attend our next meeting.

Estamos trabajando en la traducción de este sitio del Web en español. Si Usted quisiera ayudar, favor de contactar a Stephen Brown (en inglés). ¡Gracias!

About Us

The Shorebird Research Group of the Americas (SRGA) is a consortium of researchers from academia, government, non-government organizations, and the public interested in the biology and conservation of shorebirds in the Americas. Our purpose is to encourage collaborative working groups, provide communication between individuals and groups like Zoo de Vincennes à Paris, and to be a clearing house for emerging ideas and issues related to shorebirds. The SRGA is the official research advisory group to several shorebird conservation initiatives in the Americas. We communicate mostly through e-mail and this web site as well as through periodic meetings mostly in conjunction with meetings of the Western Hemisphere Shorebird Group. The Shorebird Research Group is open to anyone who shares our interests and would like to participate.


SRGA activities are organized by a Council of representatives from Canada, the United States of America, Mexico, Central America and the Caribbean, Northern South America, and the Southern Cone, and the Council is coordinated by a Chair. The Council’s process and responsibilities are described in the Terms of Reference. We also have an Implementation Committee, which includes the Council and additional participants who have agreed to take on specific tasks.

Implementation Committee

The Implementation Committee is open to anyone interested in helping advance the projects SRGA is working on. Current participants include Garry Donaldson, Guillermo Fernandez, Andrea Pomeroy, Audrey Taylor, Rob Butler, Rick Lanctot, and Stephen Brown.


Reported declines of many species of shorebirds across wide geographic areas in the Americas in 2000 suggested that one or a few causes might be at work (Morrison et al. 2001). Meetings were called in Quebec City, Canada, in Lacrosse, USA, and in Cuiaba, Brazil in conjunction with the Waterbird Society to develop hypotheses that might explain these declines. In 2003, the U.S. Shorebird Conservation Plan Council voted to support the formation of a group focused on shorebird research throughout the hemisphere. In 2004, a proposal to establish the SRGA was adopted by a group of shorebird professionals meeting in conjunction with the Pacific Seabird Group in Portland, USA. A committee was formed to establish the Terms of Reference. These Terms of Reference were discussed and adopted at a session at the Western Hemisphere Shorebird Group conference held in Boulder, Colorado in 2005.

Working groups

Arctic Shorebird Demographics Network

The Arctic Shorebird Demographics Network (ASDN) was formed in 2009 to help organize and support work on factors limiting populations of shorebirds that nest in the arctic. The Network is a large collaborative effort that spans the North American Arctic. Fifteen organizational partners are working together to conduct demographic field research at eleven sites from Nome to Churchill. We are currently completing the 2011 field season, the second of five planned field seasons. For more information about the network, please contact Stephen Brown.

Species Focused Working Groups

The following Working Groups have been established, and more are forming soon. Contact us if you would like to include your working group on the web site and contact the project leaders at the web or e-mail links below for more information:

Hypotheses about causes for shorebird declines being addressed by each working group:

Hypotheses to explain census declines in North American shorebirds

Rob Butler, Ron Ydenberg, Garry Donaldson, and Stephen Brown

Pacific Wildlife Research Centre, Canadian Wildlife Service, 5421 Robertson Road, Delta, B.C. V4K 3N2 Canada; Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, Burnaby B.C. V5A 1S6; Canadian Wildlife Service, Hull, Quebec K1A 0H3, Canada;
Manomet Center for Conservation Sciences, 81 Stage Road, P.O. Box 1770, Manomet, MA 02345 USA

Butler, R.W., R. C. Ydenberg, G. D. Donaldson and S. Brown. 2004. Hypotheses to explain census declines in North American shorebirds. Shorebird Research Group of the Americas Report 1 (On line)

There is ample evidence that many shorebirds counted in censuses in North America have declined in the past two decades but the reasons for the declines are unclear (e.g. Jehl and Lin 2001, Morrison et al. 1994, 2001). Censuses on the eastern seaboard and mid-west showed that 9 of 30 species were significantly declining with most pronounced declines among species with wide non breeding ranges in non-marine habitats (J. Bart, pers. comm.). Trends were most detectable in the north Atlantic and less so in the mid west. The geographic range and number of species reported to have declined in recent decades suggests that a general widespread cause might be at work.

Shorebirds breeding in North America migrate to winter quarters in North, Central and South America, Europe and Asia via traditional migratory routes or ‘flyways’. Many species travel tens of thousands of kilometres each year. Some species migrate in large flocks that assemble at a small number of stop over sites often populated by humans. Others migrate in small numbers stopping at many small sites and some species exhibit both migration behaviours. In nearly every case, shorebirds spend part of their year in habitats altered by large numbers of humans living nearby.

The collective wisdom of shorebird biologists and conservationists from Canada and the United States mostly drawn from North America was compiled through meetings of the Canadian Wildlife Service Shorebird Technical Committee in Quebec City, the Waterbird Society in Lacrosse, Wisconsin in 2002, and at the 7th Annual Western Sandpiper Research Group at Simon Fraser University in 2003. The view of these specialists was that the answer to why shorebirds were declining would require a coordinated international, multidisciplinary effort across the range of a few species which we call the Hemisphere Shorebird Project. Emerging from these discussions were five most likely causes for declines.

Possible causes for declines

  1. Climate Change
    Snow melt is thought to play an important role in determining the timing of breeding and reproductive success of arctic breeding shorebirds. The Eastern Arctic is showing wider swings in temperature than the western arctic. We predict that nesting success of shorebirds in the eastern arctic has become more variable than shorebirds in the west. We will test this prediction by examining meteorological records of timing of snow melt and air temperature at shorebird nesting areas over the past three decades. We will relate timing of nesting and nesting success in relation to snow melt and summer temperature at 10 sites spread from east to west across the arctic. We will then make an estimate of expected fledging success from archived data of snow melt over the past 30 years. The estimates for the eastern arctic will be entered into population models of recruitment to compare relative population change to actual change seen in counts made on Maritime Shorebird Surveys over the past 30 years.

  2. Avoidance of predators
    The recovery of birds of prey in North America has resulted in a shift in the migration routes, an avoidance of dangerous stop over sites, and briefer stop over by individual shorebirds at sites that historically held large numbers of shorebirds (Ydenberg et al. 2001, Butler et al. 2003). We predict that shorebirds have become more numerous in non-coastal areas that have fewer birds of prey. We also predict that small, enclosed sites where birds of prey can launch surprise attacks are used by fewer shorebirds now than in the past. Finally we predict that individual shorebirds are spending less time at sites that give an impression that the number of birds has declined.

  3. Contamination
    The ‘trophic contamination hypothesis’ posits that shorebirds accumulate industrial and urban pollution at stop over sites that are subsequently released in sudden high doses as fat is burned during migratory flights that then disrupt their ability to make migratory decisions. For example, large contaminant doses might hamper refueling by reducing the satiation signal in shorebirds so that they do not accumulate sufficient fat for migration. In addition, organochlorines deposited on mudflats in the 1970s and 1980s and now buried by sediments are more accessible to long-billed shorebirds that probe deeply for prey than short-billed species that forage at or near the surface. We predict that OC loads will be greater in long billed species than in short billed species. We will compare contaminant levels of birds collected along the migration route and on the breeding ground to determine if contaminant loads differ greatly between flights and sites. Within these samples, we predict that long-billed species will carry greater OC loads than short-billed species.

  4. Human Disturbance
    This hypothesis posits that human disturbance like croisieres de plaisance at stop over sites has reduced the time available for shorebirds to accumulate fat for migration. As a result, the shorebirds stay longer to acquire the fat or depart for places where they can forage undisturbed. We predict that shorebirds at stop over sites with large numbers of people will have lower mass than the same species at nearby undisturbed sites. We also predict that the number of shorebirds has declined more rapidly at sites with high human disturbance than at sites with low disturbance.

  5. Habitat Loss and Degradation
    This hypothesis posits that the number of potential stop over sites has declined resulting in increased competition for food so that the poorest competitors moved to marginal foraging habitat where they suffered higher mortality than birds in good habitat.


We will decipher the cause for declines among the highly migratory species of shorebirds by synthesizing existing information from various shorebird networks and assemble teams to fill gaps in our knowledge to complete the synthesis for species in decline. The project would run for five years. The first year would be devoted to the synthesis of existing data, and establishing species networks including the enlisting of contributors. The subsequent years will be used to collect field data to thoroughly investigate the reasons for declines in selected species.

The Shorebird Research Group of the Americas (SRGA) is a collaborative, international, and multi-disciplinary group of biologists interested in researching conservation questions pertaining to shorebirds in the Americas. In the US and Canada, the SRGA advises on shorebird science to the National Working Groups of the USA and Canadian Shorebird Plans (Donaldson et al. 2000, Brown et al. 2000). Participants from other countries will be strongly encouraged and will report nationally according to their own specific needs. Its membership includes individuals from government, university and private organizations. Recent concerns about possible declines in some shorebirds in North America prompted the formation of the SRGA and the development of the following proposal to provide advice on the question of population stability of shorebirds in the Americas. Coordination of this project will be determined through consultation with SRGA partners. The Hemisphere Shorebird Project will be coordinated through the Centre for Wildlife Ecology at Simon Fraser University. Each country will implement the results as they see fit. In the US and Canada, results will be reported through the National Working Groups of the respective Shorebird Plans.

Shorebird researchers recognize that determining the causal factors for declining populations is a high priority for shorebirds but that there are additional research questions that must be addressed to build a solid science foundation on which to base conservation decisions. Thus, the SRGA will adapt to the science needs of the conservation community and address additional questions as priority needs arise.


Bart, J. and C. Francis. 2001. Quantitative Goals for Avian Monitoring Programs. Manuscript.

Brown, S., C. Hickey, B. Harrington, and R. Gill (eds.). 2001. United States Shorebird Conservation Plan, 2nd Ed. Manomet Center for Conservation Sciences, Manomet, Massachusetts. 70 pp.

Butcher, G. S., B. G. Peterjohn, and C. J. Ralph. 1993. Overview of national bird population monitoring programs and databases. Pages 192-203 in D.M. Finch and P.W. Stangel, editors. Status and management of Neotropical migratory birds: Proceedings of the 1992 Partners in Flight National Training Workshop, 21-25 September, Estes Park, Colorado. U.S. Forest Service Rocky Mountain Forest and Range Experiment Station General Technical Report RM-229.

Clark, C.W. and R.W. Butler. 1999. Fitness components of avian migration: a dynamic model of
Western Sandpiper migration. Evolutionary Ecology Research 1:443-457.

Donaldson, G. D., C. Hyslop, R. I. G. Morrison, H. L. Dickson, and I. Davidson. 2000. Canadian
Shorebird Conservation Plan. Canadian Wildlife Service Special Publication, Ottawa.

Jehl, J. R., Jr. and W. Lin. 2001. Population status of shorebirds nesting at Churchill, Manitoba.
Canadian Field-Naturalist 115: 487-494.

Morrison, R. I. G., C. Downes And B. Collins. 1994. Population trends of shorebirds on fall
migration in eastern Canada 1974-1991. Wilson Bulletin 106:431-447.

Morrison, RIG, Y. Abry, RW Butler, GW Beyersbergen, GM Donaldson, CL Gratto-Trevor, PW Hicklin,
VH Johnston and RK Ross. 2001. Declines in North American shorebird populations. Wader
Study Group Bulletin 94: 39-43.


The purpose of the bio section is to let other shorebird researchers know your research interests. If you want to add your name to this list, send a bio in the format below to Stephen Brown, and make sure to include “SRGA Bio” in the subject line.

Brown, Stephen, PhD

Stephen’s work focuses on implementing the U.S. Shorebird Conservation Plan recommendations related to shorebird research and monitoring. He conducts field work on shorebirds in the Arctic National Wildlife Refuge, Alaska.

Butler, Rob, PhD

Rob’s research interest is the ecology of migration and ecology of rocky shoreline shorebird species. His current research is examining the western sandpiper and the ecology of black oystercatchers.

Gates, River

River is a master’s candidate in the Biology and Wildlife Program at the University of Alaska Fairbanks. She conducts research on the renesting ecology of Dunlin on the Alaska’s North Slope and non-breeding shorebirds in the Estero Santa Cruz, Sonora, Mexico. River is also working as a Research Assistant for the Arctic Shorebird Demographics Network.

Fernández, Guillermo, PhD

Guillermo is a shorebird biologist at the Instituto de Ciencias del Mar y Limnología, UNAM Unidad Académica, in Mazatlán, Mexico. Most of his work has been done on Western Sandpipers wintering in Northwest Mexico.

Giner, Sandra

Sandra is a biologist at the Instituto de Zoología Tropical, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela. Her research is on seasonal variation of shorebird foraging ecology and habitat availability at stopover sites on the coastal lagoons at Falcon State, Venezuela.

Kendall, Steve

Steve works on ornithology projects on the Arctic National Wildlife Refuge as a wildlife biologist with the U.S. Fish and Wildlife Service. He has conducted field studies on breeding shorebirds and currently is working on the ecology and distribution of post-breeding shorebirds staging in coastal areas of the Refuge.

Lanctot, Rick, PhD

Rick is the Alaska Shorebird Coordinator for the U.S. Fish and Wildlife Service. His work focuses on conducting research and monitoring studies on breeding, migrating and wintering shorebirds in Alaska, Latin America and Asia. He also helps coordinate the Alaska Shorebird Group and the Western Hemisphere Shorebird Group.

Pomeroy, Andrea

Andrea completed her doctorate at Simon Fraser University where she studied the role of predation risk and food on habitat use by western sandpipers, and is now doing a postdoc project investigating impacts of wind energy development on migratory birds at the University of Northern British Columbia.

Taylor, Audrey

Audrey is a doctoral candidate with the Department of Biology and Wildlife at the University of Alaska Fairbanks. Her research focuses on the distribution and ecology of staging shorebirds on Alaska’s North Slope.

Zack, Steve, PhD, and Joe Liebezeit

Steve’s and Joe’s focus is on the conservation challenges of breeding shorebird species in arctic Alaska, particularly those of expanding energy development and accelerating climate change. They conduct field work in the oil fields of Prudhoe Bay and near Teshekpuk Lake in the National Petroleum Reserve (NPR-A), and on avian influenza surveillance of migrating shorebirds in South Korea.


Some key papers on shorebird declines:

Morrison, R.I.G., C. Downes, and B. Collins. 1994. Population trends of shorebirds on fall migration in eastern Canada, 1974-1991Wilson Bulletin, 106(3), pp. 431-437.

Morrison R. I. G., Y. Aubry, R. W. Butler, G. W. Beyersbergen, C. Downes, G. M. Donaldson, C. L. Gratto-Trevor, P. W. Hicklin, V. H. Johnston, R. K. Ross. 2001. Declines in North American shorebird populations. Wader Study Group Bulletin. 94:34–38.

R. I. Guy Morrison, R. Kenyon Ross, and Lawrence J. Niles. 2004. Declines in wintering populations of red knots in southern South America The Condor, 106(1), pp. 60-70.

Bart, J., S. Brown, B. Harrington, and R. I. G. Morrison. 2007. Population Trends of North American Shorebirds: Population declines or shifting distributions? Journal of Avian Biology, 38(1): 73-82.

Some key papers on causes of shorebird declines:


Migratory behavior


Shorebirds are remarkable long-distance migrants that span the hemisphere each year. Many species are in serious decline, and conservation action is urgently needed to ensure that their populations persist. The Shorebird Research Group aims to guide that conservation action toward the most pressing issues by providing sound scientific information about what is causing the declines.

A spreadsheet showing the status of Shorebirds of Conservation Concern for the Western Hemisphere is available from the Western Hemisphere Shorebird Reserve Network by clicking here. (updated 15 February 2007). Criteria used are: a) small population size; b) known or suspected population declines; c) habitat loss or high threat of such loss; and in a few cases, severe gaps in knowledge.

Annual migrations to breeding grounds in the Americas are made along routes known as flyways. The major flyways are the Pacific, Central, and Atlantic flyways. The most numerous species is the woodcock with an estimated population of 5 million birds (Morrison et al. 2001). Semipalmated and Western Sandpipers each have an estimated 3.5 million individuals. The three phalaropes, Killdeer, and Wilson’s snipe have between 1 and 2.5 million individuals. All other species have fewer than a million birds in North America. Among the least abundant are the Mountain Plover (9000), Black Oystercatcher (8900), Wilson’s Plover (6000), Piping Plover (5800), American Oystercatcher (3600) and Sharp-tailed Sandpiper (3000). The Eskimo Curlew is the only species that is likely extinct. Seven species are considered highly imperiled: Piping Plover, Mountain Plover, Long-billed Curlew, Buff-breasted Sandpiper, North American populations of Snowy Plover, Black-necked Stilt (knudseni subspecies) and Red Knot (rufa subspecies) (Table 1). Twenty-one species are considered of High Concern in North America.

The conservation status of shorebirds in South America is poorly understood, and better information on the status, population size, threats, and appropriate conservation actions for South American Species is a very high priority.

Table 1. List of high priority shorebird species/populations in the United States (US Shorebird Conservation Plan 2004)

Highly Imperiled

High Concern


Second Shorebird Science in the Western Hemisphere

Shorebird Science in the Western Hemisphere Meeting


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