June - July 2010
Water lily in Coot Slough at Powdermill
Although we banded two Swainson's Warblers during spring migration (see spring highlights) and at least one of these seemed to be territorial for awhile, we were unable to document successful breeding by capturing young Swainson's Warblers during the summer. The most commonly captured birds this summer included the American Redstart (128), Gray Catbird (100), Cedar Waxwing (55), and Hooded Warbler (39).
During early summer we capture a lot of breeding Yellow Warblers as they establish and defend their territories around the banding area. Photographed is a SY male banded in June.
The following sequence of photographs were taken of a nestling Northern Cardinal over a period of several days and demonstrate how quickly nestlings can grow.
Cardinals grow so quickly that they are able to fledge from the nest only 9 days after hatching.
Although cardinals can lay as many as 5 eggs in a given clutch there were only 2 eggs present in this nest, and only one of those proved viable and hatched.
This Veery was captured with its halix (the toe facing backwards) claw caught in the band. This was unusual and it is not clear how the bird got the claw stuck in the band. The claw was carefully removed from the band. Although this individual was in good condition and seemed to be doing fine despite the inconvenience, it likely was quite content having full use of its halix again.
Late summer is a time when there is an abundance of fledglings moving through the area and some of these can be quite challenging to identify. For example, fledgling Swamp and Song Sparrows can look nearly identical. With practice they can be quickly identified by looking at the difference in their bill morphology. The Swamp Sparrow has the thin pointed bill compared to the wider and chunkier looking bill of the Song Sparrow. Once these birds undergo their first prebasic molt they will be easily distinguishable by their plumage alone. In the photograph, the bird in the front is the Swamp Sparrow and the one in the back (right) is the Song Sparrow.
In mid July we had some interesting captures which included our second Cerulean Warbler of the year. The bird was identified as a hatching year male, and if you look closely you can see the blue coloration beginning to come in on the uppertail coverts.
In late July we captured this adult male American Redstart. In this bird, notice the very extensive orange wing patch which extends onto the greater coverts, which are usually all black.
This hatching year Tufted Titmouse shows a very strong fault bar across its wing coverts, remiges, and retrices. In all of these feathers the fault bar is at the tip of the feather, which means that they were created just as the feathers began to grow. This indicates that when this bird was a young nestling (just a few days post hatching) it underwent a period of limited food uptake. The nutritional stress caused by this resulted in the stoppage of feather growth, which left behind the fault bar once the feathers resumed growth.
Although female house finches are usually all brown, this adult female had some red coloration on its head. In many species older females are more colorful than young ones and can begin to resemble males. This phenomenon has been documented with Hooded Warblers where the plumage of older females can resemble that of males.
It was the summer of the Timber Rattlesnake at Powdermill. Whereas this species used to be rarely encountered at Powdermill they have been spotted with increasing frequency over the last few years. We had documented a single individual in the banding area over the last 2 summers. This summer we have encountered at least 8 individuals in the banding area and they are turning up in other places across the reserve as well. Although they are truly a beautiful animal, it has us walking the banding area much more carefully these days.
Amy Amones (bioacoustics specialist) admiring an adult male Scarlet Tanager.
Gray Catbirds are one of the most commonly captured species throughout the summer at Powdermill. In the picture Mary Shidel is processing one of many Catbirds.
Carolyn (a new volunteer at the banding lab) holding a Cedar Waxwing.