Friday, August 22

Nocturnal migrants August 2014

The following were recorded over my home in Elkins Park, PA during August. All identifications are presumptive.
Least Bittern (3.24am, early Aug)

Upland Sandpiper (3.26am, mid-Aug).

Black-billed Cuckoo (4.32am, early Aug).

Chestnut-sided Warbler, a relatively low fine buzz (12.13am, mid-Aug).

Compare with the higher, lazier buzz of Yellow/Blackburnian/Blackpoll/Connecticut Warbler. Most likely a Yellow based on the date (3.05am, early Aug).

The Common Yellowthroat call is usually easily separable as a low electric buzz, but calls are variable and not always double banded, as here (2.55am, mid-Aug).

Here's a nice comparison between American Redstart and Black-and-white Warbler, The calls have a similar shape but the sound is quite different (mid-Aug).

Canada Warbler can sound a bit like American Redstart, but is very different on the sonogram (3.24am, early Aug).

The Cape May Warbler call is sharp, high and usually descending (5.33am, mid-Aug).

Shortly before dawn, some warblers call frequently as they descend, similar to the vocal behavior of Catharus thrushes. Ovenbirds with a Mourning Warbler calling, a few Bobolinks in the background at the end (5.41am, mid-Aug).

Mourning Warbler is the lower call

Friday, April 4

American Bittern/Black-crowned Night-Heron nocturnal call comparison

A couple of nights ago I recorded this sequence of an American Bittern and Black-crowned Night-Heron calling together as they flew over my house (2.04am, early Apr, PA).

bittern on left, night-heron on right

The night-heron can give very low calls, even lower than the bittern, but there's generally a rising element to them.
These calls from the Macaulay Library were at a breeding colony and are not typical nocturnal flight calls.

As always, nocturnal call id's are presumptive as the birds were not visible.