In October the Lesser Snow Geese start arriving at the George C. Reifel Bird Sanctuary. These birds migrate from Wrangel Island, which is in the Arctic Ocean and is part of Russia. To give you an idea of the numbers, according to Reifel’s website the 2015 snow geese count was 75,000. They usually winter out in the estuary and don’t get close to the trails or ponds (or I haven’t been lucky enough to witness that) but the flocks continuously fly overhead (and are very noisy).
I have seen them congregate in the neighbouring farmers fields though.
We make a point of going to the bird sanctuary at least one every winter to witness these white beauties (not to mention all the other migrating birds).