Sunday, September 23, 2012

Highlights From September 17th- 23rd

This week saw two cold fronts which brought in some later migrants such as Winter Wren (WIWR), kinglets, Brown Creeper (BRCR) and more Red-breasted Nuthatches (RBNU).  

GCKI- The kinglet with the striped head
Diversity of warblers increased over the week with 22 species being seen or heard: Tennessee, Nashville, Northern Parula, Chestnut-sided, Magnolia, Cape May, Black-throated Blue, Myrtle, Black-throated Green, Blackburnian, Western Palm, Bay-breasted, Blackpoll, American Redstart, Black-and-white, Ovenbird, Northern Waterthrush, Connecticut, Mourning, Common Yellowthroat, Wilson's, and Canada.

As predicted, an increase in the numbers of Blackpoll Warblers occurred and should only increase over the next couple weeks. In a repeat of last year, when we had several previously banded BLPWs return to the migration site, this week we had one return of a BLPW that was banded last September. Just another reminder of how important these migratory stopover habitats are to these long distance flying birds.
Just for fun here is a warbler line up for you to identify the species:

One of the difficult fall warbler species to identify is the Cape May Warbler (CMWA). If you have a nice adult male with the presence of yellow on the breast and fine dark streaks and large white wing bar identification is much easier. However, most Cape Mays in fall are not that colorful. They still have their fine streaks on their breast and a shadow of the facial disk but this can be challenging in the field. One thing that may be helpful to you is the bill shape and size in relation to the head shape for the CMWA. For example, CMWA and American Redstart (AMRE):

AMRE is a flycatching warbler which has a broad bill and lots of modified feathers called rictal bristles (whiskers). The Cape May has a fine pointed bill and small head compared to its body. CMWA's bill is often encrusted with pollen from tropical plants in the spring when we capture them.
CMWA-left and AMRE-right

Now take a look at the head and bill shape of this CMWA
and a female Black-throated Blue Warbler (BTBW):
CMWA-left and BTBW female-right
You have the fine bill of the CMWA and small head, whereas, the bill and the head shape on the BTBW is much larger in comparison. Feeding habits differ among the species and we can use body differences to aid with ID. Hope this look at bill shape and size is helpful to you in the field.

Dorsal view of a Brown Creeper (BRCR) with rufous rump

BRCR-note curved bill for probing for insects/spiders under bark
Enjoy the week! More kinglets, WIWRs, and I would expect Orange-crowned Warbler and Hermit Thrush to be seen soon!

Check out the navarre banding summary at
to see where we are at in migration this fall. We try to update this file each Friday.

Here are the answers to the warbler line-up from left to right:

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