On my way out of the park today, at dusk, I heard a strange buzzing call that sounded very similar to this:
http://www.youtube.com/watch?v=Ub6A_hh7_r8.
I heard the call three or four times, always just one buzz. I didn't get a visual, as it was already getting dark and the call was coming from the large scrubby baselands area. It doesn't seem like there are any other birds that sound remotely like this, but I'm not ruling out some sort of insect (although apart from a few clouds of gnats, there don't seem to be many insects around yet). Anyone know any bugs around that might be causing this confusion?
Other observations from today:
Canada Goose 24
Mute Swan 4
Trumpeter Swan 2
Gadwall 26
American Wigeon 2
Mallard 54
Canvasback 16
Greater Scaup 9
Lesser Scaup 4
Greater/Lesser Scaup 11
Long-tailed Duck 121
Bufflehead 53
Common Goldeneye 2
Common Merganser 80
Red-breasted Merganser 50
Double-crested Cormorant (Dark-crested) 70
Killdeer 12
Ring-billed Gull 5000
Herring Gull 9
Iceland Gull 1
Rock Pigeon 2
Mourning Dove 1
Downy Woodpecker 1
Northern Flicker (Yellow-shafted) 1
Eastern Phoebe 1
Tree Swallow 3
Black-capped Chickadee 6
Brown Creeper 3
Golden-crowned Kinglet 11
American Robin 56
European Starling 65
American Tree Sparrow 7
Song Sparrow 56
Dark-eyed Junco (Slate-colored) 15
Red-winged Blackbird 71
Common Grackle 9
Brown-headed Cowbird 3
House Sparrow 2