Monday, June 29, 2009

More on the Frozen Shorebirds

Since I posted on this once already, I would like to post an update on the breeding conditions in northern Canada. First, the BSI blog has posted some additional photographs from frozen areas. Most come from the Northwest Territories, but there are also a few from northern Quebec. Secondly (again via the BSI blog), some Ontarian ornithologists emailed a summary of breeding conditions via a birding listserve. Conditions are not uniformly bad. Spring across the Arctic was 2-3 weeks late, so that breeding will likely be reduced, but not a total washout. The worst conditions appear to be in Manitoba and the Northwest Territories.

I am reproducing the location summaries below:

Ontario: Ken Abraham reports that conditions in the Hudson Bay Lowlands were about 10 days late from Attawapiskat south on James Bay, including Akimiski Island, with Canada Geese and Snow Geese hatching in mid June, more like the 1990s average than the 2000s average and within the overall norms. Other species on Akimiski Island were correspondingly late. His guess is that for those species that require shorter time there will be some reduction but not huge. Perhaps the predation effect will be somewhat greater if alternate species are less available. Because coastal snow, ice and water inundation conditions were similar from Cape Henrietta Maria to the Manitoba border, Ken expects that for Canada Geese nesting within 40-60 km from the coast, a much reduced effort and productivity will be the norm. Snow Geese at Cape Henrietta Maria were greatly down and the suggestion of a 90% reduction seems to fit what they saw on their survey. However, beyond 40-60 km inland, he thinks conditions will be different. Mark Peck said that species nesting away from the Hudson Bay Coast in boreal bogs and fens such as yellowlegs should not be severely impacted because much of the freeze took place near the coast.

Manitoba: The situation is worse in northern Manitoba at Churchill where temperatures were well below normal until recently and the snow cover melted late. However, Erica Nol reports that birds have started to nest, just very late, and it won’t be a complete bust for shorebirds if there are enough bare spots. Whimbrels and Hudsonian Godwits are nesting, but overall nesting success should be below average for most shorebirds in northern Manitoba.

Nunavut: Snow melt was up to three weeks late in mainland Nunavut north of Manitoba. Recent temperatures have been close to normal. Much of Baffin Island is now snow free and conditions there and on Bylot Island are about normal. High Arctic breeders should have a good breeding year.

Northwest Territories: Vicky Johnston suspects it will be a poor breeding year in parts of the Western Arctic. Spring was roughly three weeks late in Yellowknife on Great Slave Lake based on leaf-out. The Mackenzie Valley and Delta warmed early but then cooled off again. The Delta flooded slowly and the water receded slowly, so some prime shorebird breeding areas were subject to heavy predation.

Yukon: Cameron Eckert reports a late spring, but once the heat came, everything shifted into high gear.

Alaska: Declan Troy reports from the North Slope that the snow on the tundra is long gone. It was much warmer earlier in the month and his guess is that the breeding season has been early there.