KEY NORTH AMERICAN MIGRATION SITES FOR
Red Knots & Semipalmated Sandpipers

Nelson River Estuary, western Hudson Bay

Country: Canada

Region: Manitoba,

Site: Nelson River Estuary, western Hudson Bay

Species/Sub-species: REKN-rufa

Total biogeographic population: 42,000

Count Method: Two-day maximum count

Count: 4,2591

% biogeographic pop. at site: 10.14

Season (primarily): Spring

Site recognition: WHSRN IBA

Site recognition (other): Wapusk National Park, Kaskatamagan Wildlife Management Area

Site description: Using the Ramsar Classification System for Wetland Type, the site habitat characteristics are coastal (intertidal marshes, including saltmarsh and extensive mudflats). Land ownership is provincialand federal. All shorebirds were observed in saltmarsh, or at the outflow of freshwater streams, suggesting the importance of these habitats in spring. The coastal area between the Nelson River and the Ontario border has been designated as a Wildlife Management Area – the ‘Kaskatamagan Wildlife Management Area’ – but only the central portion of the area, farther east from where Red Knots were detected during the aerial survey, is protected from development. Work currently underway at the site in 2016 included shorebird moniting with geolocators.

Known threats: The threat of exploitation of renewable resources is moderate due to energy production and mining in the form of renewable energy (hydroelectric development), which has the potential to influence habitat suitability. Understanding the potential impacts of threats in the area, including hydroelectric development on the Nelson River and overabundant Snow Geese Chen caerulescens caerulescens, is a critical next step in protecting the rufa subspecies from further declines.

Notes: The site boundaries are defined as the area between Churchill, Manitoba, and East Pen Island. Geolocator results also suggest that a significant proportion of the populations from both the West Atlantic and Mid-Continent flyways and from multiple stopover and wintering sites may use this area in any given year1,2.

Sources: 1McKellar, A.E., R.K. Ross, R.I.G. Morrison, L.J. Niles, R.R. Porter, J. Burger, D.J. Newstead, A.D. Dey, P.A. Smith. 2015. Shorebird use of western Hudson Bay near the Nelson River during migration, with a focus on the Red Knot. Wader Study 122(3): 201–211. 2Newstead, D.J., L.J. Niles., R.R. Porter,A.D. Dey, J. Burger and O.N. Fitzsimmons. 2013. Geolocation reveals mid-continent migratory routes and Texas wintering areas of Red Knots Calidris canutus rufa. Wader Study Group Bulletin 120(1): 53–59.