The Toronto Whimbrel Watch

 

At 5:30am on May 22, 2024, light breaks in the eastern sky as birders gather with anticipation at Whimbrel Point in Toronto’s Colonel Samuel Smith Park on the north shore of Lake Ontario. A short peninsula juts south, which gives observers panoramic views in every direction. We eagerly scan the lake with scopes and binoculars, watching, listening, and waiting. Suddenly, we hear the haunting musical trill even before we see a flock of large brown shorebirds with long decurved bills flying toward us from the southeast. We count the Whimbrels, 76 in the flock. They circle over us and the lake several times as if checking the contour of the land below. Then they fly north and out of sight. Next stop: Hudson Bay.

These Whimbrels have flown all night. They took off the evening before from staging areas on the east coast of the U.S., where, for several weeks, they fattened up on fiddler crab eggs in the rich coastal marshes. Toronto is another dot on their northbound migration route from wintering grounds on the east coast of South America to breeding grounds in the Canadian Arctic, a total distance of 8,000 km (4,971 miles) for the Hudson Bay population and 11,000 km (6,835 miles) for the Mackenzie River Delta population in the Northwest Territories.

The Thrill of the Count

Tired Whimbrels take a rest on May 25, 2015. Photo by © Jean Iron.

Thus begins Day 3 of the 2024 Fred Bodsworth Memorial Whimbrel Watch in Toronto, which ran from May 20 to May 26, with counter Eric Baldo keeping score. Every evening of the count, Alexandra Wilke at The Nature Conservancy of Virginia’s Box Tree marsh, Machipongo, sends Eric the number of Whimbrel that left Box Tree marsh on that evening. Each morning, Eric posts this number as the day’s forecast on our Ontario Bird Alert Discord server, followed by a summary at the end of each day.

The forecast on Day 3 was that 2,289 Hudsonian Whimbrels left Box Tree in Virginia the previous evening, and this could be a stellar day. Eric’s end-of-day summary confirmed: “Another spectacular total count of 1,547 Hudsonian Whimbrels passed by Whimbrel Point today, the majority arriving bang on schedule, right in the early morning! A massive flock of 500 Whimbrel delighted observers as they emerged out of a foggy Lake Ontario. This was truly a highlight of the morning! Our total count represents more than half of what took off from Box Tree in Virginia last night!”

Eric counts, leads, and educates the birding community and the public. Whimbrel may appear at any time during the day, though mornings have the highest numbers. Every flock delights the watchers, and some fly very close to the point. There is big excitement when a flock puts down to rest on the rocky shoreline. When this happens, we cordon off the area to give the shorebirds uninterrupted rest.

Eric reported that the 2024 season’s final tally was 5,954 flying past Whimbrel Point, making it one of the best counts. He acknowledged the contributions of birders who came out, helped spot, documented with photos and videos, posted checklists on eBird, and participated in the birding camaraderie.

The Origins of a Name

This Whimbrel sports a transmitter. May 26, 2021. Photo by © Amanda Guercio.

Whimbrel is a type of curlew. Its original name was Hudsonian Curlew (Numenius hudsonicus) in North America until the 1944 AOU Check-list Supplement, when it was lumped with the European Whimbrel and became Whimbrel (Numenius phaeopus). Hudsonian Curlew (Numenius phaeopus hudsonicus) continued as its subspecies name in the 1957 AOU Check-list, then in the 1983 AOU Check-list, the subspecies became hudsonicus group. A 2022 proposal to the American Ornithological Society North American Classification Committee to split Numenius hudsonicus (Hudsonian Curlew) from N. phaeopus (Whimbrel) did not pass.

In 2020, the International Ornithological Congress (IOC) recognized Hudsonian Curlew as a separate species, and the current IOC World Bird List, version 14.2, uses the English name, Hudsonian Whimbrel (Gill et al. 2024). At the time of writing this article, eBird recognizes the subspecies Numenius phaeopus hudsonicus with the English name Whimbrel (Hudsonian) and Numenius phaeopus phaeopus with Whimbrel (European).

History of Whimbrel Watching in Toronto

Whimbrels cruise past Whimbrel Point at Colonel Samuel Smith Park along Lake Ontario. Photo by © Lev Frid.

Whimbrel watching is a tradition in Toronto. Early Toronto ornithologists noted the impressive spring migration of the eastern population of Whimbrels, known as Hudsonian Curlews, which flew past Toronto on spring migration in a narrow time frame from about May 20 to May 28. Hunters in the late 1800s and early 1900s also knew of these concentrations, and hunted them and other shorebirds to the point of bringing their populations to critically low levels, even extinction for the Eskimo Curlew. The intense hunting also made them very wary and difficult to approach. Fortunately, the 1916 Migratory Birds Convention Act between Canada and the U.S. afforded protection to Hudsonian Curlews and other shorebirds. Today, according to The State of Canada’s Birds (2024), the Whimbrel population continues its steep decline, having lost close to 80% of its abundance since the 1980s (Smith et al. 2023).

May 24 is Victoria Day, a federal holiday in Canada. In Richard Saunders’ Flashing Wings, a 1947 book about birding in Toronto and southern Ontario, he called it Hudson Curlew Day because this was considered the peak date of spring migration (Field 2010). Continuing the Toronto Whimbrel watching tradition, in 2007, several birders conducted an unofficial watch at Colonel Samuel Smith Park and posted results on the Ontbirds listserv. This report caught the attention of Fletcher Smith, a Whimbrel researcher at the Center for Conservation Biology at The College of William and Mary and Virginia Commonwealth University. Fletcher contacted us and encouraged a more rigorous approach to Whimbrel watching.

In 2009, I and several members of the Toronto Ornithological Club organized an official watch at Colonel Samuel Smith Park with a counting protocol similar to the one at regional hawkwatches. The Toronto Whimbrel Watch now runs every year from about May 18 to May 30, from 5:30am to 5pm, and is named after Fred Bodsworth, a well-known Toronto birder and author of the award-winning Last of the Curlews, a poignant fictional account of the last Eskimo Curlew.

Also in spring of 2009, using the same protocol as the Toronto Whimbrel Watch, The Center for Conservation Biology and The Nature Conservancy of Virginia initiated an evening watch to count Whimbrels as they left Box Tree marsh during the last two weeks of May. Fletcher Smith reported: “All birds appear to leave the Eastern Shore of Virginia during the four hours before dusk. The objective of this effort is to understand the phenology for birds staging along the Delmarva Peninsula and to make comparisons with counts of Whimbrels moving through the Greater Toronto Area and on to breeding grounds” (Smith Sept.2010).

Tracking Whimbrel: Virginia

To learn more about staging areas in Virginia, migration through the Great Lakes, and breeding locations in the Canadian Arctic, in May 2009 researchers in Virginia used five satellite transmitters to track migrating Whimbrel. On June 3, 2009, all five Whimbrels with satellite transmitters were in northern Ontario (Renaud et al. 2009). That same year, the Toronto Ornithological Club and the Toronto and Region Conservation Authority partnered with The Center for Conservation Biology to place a receiver/datalogger at Colonel Samuel Smith Park. Ten of 32 Virginia Whimbrel with radio transmitters were detected at the park between May 22 and May 28 (Watts 2009; Smith Apr. 2010)!

  In 2010, two more dataloggers were placed on the Lake Ontario shore, and Ontario birders donated enough money to purchase 13–14 radio transmitters to be put on in Virginia (Field 2010). On May 23, 2010, at Tommy Thompson Park in Toronto, Mike Dizonno photographed a flock of flying Whimbrel which included one with a transmitter. Fletcher Smith, with the Virginia Whimbrel Migration Study, identified it as one of 18 radio-tagged Whimbrel in Virginia in Apr. and May 2010 (Smith Sept. 2010).

South Carolina

We considered that some Whimbrels we observe may originate in other known staging areas in the coastal marshes of Georgia and South Carolina. At the Toronto Watch on May 23, 2021, Amanda Guercio spotted and photographed a Whimbrel with a transmitter on its lower back and a light green flag with black lettering, denoting it was tagged in the U.S. Eric Baldo contacted Whimbrel researcher Maina Handmaker, who confirmed that this Whimbrel was tagged in South Carolina in May 2021. However, this Whimbrel was only tracked in 2021 during its first May stopover in South Carolina. It lost its transmitter or did not return to South Carolina for researchers to download data indicating its breeding and nonbreeding grounds, and no other returning Whimbrel passed over Toronto (Maina Handmaker pers. comm. 2025).

Fortunately, on May 29, 2021, east of Toronto at Presqu’ile Provincial Park, Doug McRae spotted a similarly marked Whimbrel with a transmitter and a light green flag EJ2. Maina Handmaker informed me that this Whimbrel was tagged in South Carolina in the same spring as the Whimbrel that was sighted in Toronto. “EJ2 traveled to their nesting site in lower Hudson Bay in spring 2021 and 2022, and both years used James Bay as a post-breeding staging area before making an open ocean flight to non-breeding grounds in Maranhão State, Brazil. EJ2 was detected by our towers again in Spring 2023.” The map shows EJ2’s movement tracks for 2.5 years.

Whimbrel with a White Rump

At the Toronto Whimbrel Watch on May 22, 2012, a Whimbrel with a white rump, a “V” up the back, white axillaries, and white underwing coverts was spotted in a flock of 55 North American Whimbrel, which have brown rumps. It likely belonged to the Old World phaeopus subspecies group breeding from Iceland to western Siberia, which infrequently occurs as a vagrant in North America, typically in the northeastern U.S. or Atlantic Canada. Another possible subspecies was the eastern Siberian subspecies variegatus. The vigilance and keen eyes of these dedicated observers yielded an exciting Whimbrel rarity amidst the Hudsonians.

Summary

We love Whimbrel and are delighted when we hear and see them in Toronto each May. We marvel at their long migrations from coastal areas in Brazil to the marshes of the U.S. East Coast and to the tundra breeding grounds of the Canadian Arctic. We recognize that international cooperation is needed to prevent further declines in Whimbrel populations and help them stabilize. We are happy that the Fred Bodsworth Memorial Toronto Whimbrel Watch contributes to knowledge about Whimbrel migration through the collection of data, cooperation with tracking and research programs, and involvement in the International Shorebird Survey.

Acknowledgments

I thank fellow birders for their involvement: Wayne Renaud, Mark Cranford, Don Barnett, Timothy McCarthy, Eric Baldo, Nancy Barrett, Garth Riley, Marc Lichtenberg, Terry Smith, Bruce Wilkinson, and David Creelman. The Toronto Ornithological Club sponsors the watch, and Friends of Sam Smith Park give their support. Fletcher Smith of The Center for Conservation Biology in Virginia provided valuable input and established the relationship that continues today. Maina Handmaker, researcher in South Carolina, provided information about tagged Whimbrel and her research. Christian Friis of Environment Canada, Canadian Wildlife Service, provided population information and registered the Toronto Whimbrel Watch for the International Shorebird Survey. I also thank all the birders who come to the watch, bringing their enthusiasm and passion for Whimbrel.

Literature Cited

American Ornithologists’ Union (AOU). 1957. Check-list of North American Birds, fifth edition. American Ornithologists’ Union. Baltimore, Maryland.

American Ornithologists’ Union (AOU). 1983. Check-list of North American Birds, sixth edition. American Ornithologists’ Union. Lawrence, Kansas.

American Ornithological Society Classification Committee: North and Middle America. 2022, p. 73–78. https://americanornithology.org/wp-content/uploads/2022/04/2022-A-final.pdf.

Chesser, R. T., S. M. Billerman, K. J. Burns, C. Cicero, J. L. Dunn, B. E. Hernández-Baños, R.
A. Jiménez, A. W. Kratter, N. A. Mason, P. C. Rasmussen, J. V. Remsen Jr., D. F. Stotz, and K. Winker. 2022. Sixty-third supplement to the American Ornithological Society’s Check-list of North American Birds. Ornithology 139 (3). https://doi.org/10.1093/ornithology/ukac020.

Environment Canada and Birds Canada. 2024. The State of Canada’s Birds 2024. https://naturecounts.ca/nc/socb-epoc/report/2024/en/.

Field, M. 2010. Hudsonian Curlew Day. Toronto Ornithological Club Newsletter 205: 3–4.

Gill F., D. Donsker, and P. Rasmussen (eds). 2024. IOC World Bird List (v14.2).

Handmaker, M. C., F. J. Sanders, A. D. Smith, E. P. Shealy, N. Fontaine, M. B. Kaplin, J. M. Thibault, M. C. Martin, C. Duquet, A. V. Sterling, and N. R. Senner. 2024. Individual foraging site fidelity persists within and across stopover seasons in a migratory shorebird, Numenius phaeopus (Whimbrel). Ornithology 141: 1–14.

Iron, J. 2010. Tagged Whimbrel. Toronto Ornithological Club Newsletter 207: 9. https://www.jeaniron.ca/articles/TOC_Newsletter_2010-09%20(2).pdf.

Renaud, W., M. Cranford, and J. Iron. 2009. Whimbrel Watch: Colonel Sam Smith Park, Etobicoke. Toronto Ornithological Club Newsletter 196: 10–11.

Smith, F. 2010. Migration ecology of the Whimbrel. Toronto Ornithological Club Newsletter. 204: 11–12.

Smith, F. 2010. Overview of spring 2010 Whimbrel Migration Study. Toronto Ornithological Club Newsletter 207: 6–8. https://www.jeaniron.ca/articles/TOC_Newsletter_2010-09%20(2).pdf.

Smith, P. A., A. C. Smith, B. Andres, C. M. Francis, B. Harrington, C. Friis, R. I. G. Morrison, J. Paquet, B. Winn, and S. Brown. 2023. Accelerating declines of North America’s shorebirds signal the need for urgent conservation action. Ornithological Applications 125 (2). https://academic.oup.com/condor/article/125/2/duad003/7031074.

Watts, B. 2009. Whimbrel Connections. The Center for Conservation Biology. https://ccbbirds.org/2009/05/07/whimbrel-connections/.

Watts, B., and F. Smith. 2010. Hope the Whimbrel Returns. The Center for Conservation Biology. https://ccbbirds.org/2010/03/05/hope-the-whimbrel-returns/.

Watts, B. D., F. M. Smith, C. Hines, L. Duval, D. J. Hamilton, T. Keyes, J. Paquet, L. Pirie-Dominix, J. Rausch, B. Truitt, B. Winn, and P. Woodard. 2021. The annual cycle for Whimbrel populations using the Western Atlantic Flyway. PLoS ONE 16 (12): e0260339. https://doi.org/10.1371/journal.pone.0260339.

Wetmore, A., H. Friedmann, F. C. Lincoln, A. H. Miller, J. L Peters, A. J. van Rossem, J. Van Tyne, and J. T. Zimmer. 1944. Nineteenth Supplement to the American Ornithologists’ Union Check-list of North American Birds. The Auk 61 (3): 441–464.