20 March 2009

BCV & I




Black-capped Vireos (Vireo atricapilla) "BCVI" and I have both returned to the Lone Star State.

*The pictures in this posting were taken while I worked as Golden-cheeked Warbler Field Biologist for The Nature Conservancy at Ft. Hood. Disregard the red-headed stranger in the background warding off evil-spirits with the power of the vireo.*

The BCVI has returned from Mexico (atleast 2 have). I have returned from San Diego and San Clemente Island.

We finally met again, yesterday 19 March, in Kerr County, TX.

Great birds (aren't they all) that share some similarities in vocalization with Blue-gray Gnatcatcher (Pelioptila caerulea), the White-eyed Vireo (Vireo griseus), and even the Ruby-crowned Kinglet (Regulus calendula). (Pope, pers. communication)

The BCVI is often thought of residing primarily where Shin Oak (Quercus sinuata) exists. This belief may, in fact, bias our surveying for BCVI.

It is being discovered that the BCVI almost seem more interested in structure than species specific (Pope, pers. communication) regarding vegetation communities preferred, even for nest substrate.

I was shown several old BCVI nests in Kerr County that were, in fact, located in young-er mottes of Live Oak (Quecus viginiana).

Nests were also found last year, though infrequently, in Red Oak (Quercus texana) and Agarita (Berberis trifoliolata). Nest are almost always only 1-2 meters above the ground. (Pope, pers. communication)

The BCVI suffers greatly from brood-parasitism by the Brown-headed Cowbird (Molothrus ater). This species' female will lay her eggs in the nests of other species, in our case the endangered BCVI. All this to the detriment of the parasitized species as that species will then raise the cowbird young. The cowbird chick is usually far larger than the parasitized species' nestlings.

The other threats to the BCVI nests are predators such as Western Srub Jays (Aphelocoma californica) and other members of Family Corvidae.

One of the primary threats to the nest, though, is the Texas Rat Snake (Elaphe obsoleta lindheimerii).

All of these preceding threats are naturally occuring.

BCVIs are endangered due to the ol' faithful ... habitat destruction.

They no longer exist in Kansas. There is a small relict population in Oklahoma.

The next several months I will be working for Texas A&M University. More specifically working within a research project focusing on landowners creating, restoring, enhancing, and protecting native habitat for rare or at-risk species throughout the state. In particular for us the BCVI, a federally-listed endangered species. These land owners, with their respective private lands, are part of the Landowners' Incentive Program (LIP).




The picture on the right is not of my hand. I would never wear nail polish. Not pink anyways...

-matt

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