Friday, September 17, 2010

Bentsen-Rio Grande Valley State Park - Bio Blitz - Park Still Closed

I had the opportunity to go into Bentsen September 9 as part of a bio-blitz. Special permission was required to participate in the event, and permission was only for the one day. Bentsen is still CLOSED due to flooding, but the Headquarters including the coffee shop and store are open.

Here's some pictures of the park after the flood. I am hoping that the flood will rejuvenate the riparian forest, which has been starved for nutrients since Hurricane Beulah, shortly after the construction of Falcon Dam.

The park was extremely birdy with lots of migrants, water birds, and resident species. My group saw tracks of Collared Peccary and Raccoon. Herons and egrets were flying over much of the day.

Here's the entrance road looking south near the maintenance yard.
And the drainage canal on the entrance road, full of water.
The Resaca Vieja Trailhead - the trail is still nearly blocked by a downed tree.
You can see the water level on the vegetation here, looking south to the Ebony Grove.
One of the feeding stations on the entrance road.
Kingfisher overlook.
The picnic pavilion - again, note the water line on the building.
Kiskadee Trail
Trailer loop - Acacia Loop
North end of the Acacia Loop
Roadrunner Crossing at the north end - still a lot of water over the road!
A lot of the brush was flooded, and the invasive guinea grass was dead. Northern Waterthrushes were enjoying the wet spots!
Northern Beardless Tyrannulet nest with young - note that the adult has food for the chicks in the ballmoss nest.

Tuesday, September 7, 2010

Doug Weidemann's pictures - Yellow-green Vireo - Sept. 6, 2010

Here are Doug Weidemann's photos of the Yellow-green Vireo from September 6, 2010. The Yellow-green Vireo was first found at Cannon Road (AKA Old Cannon Road Pond) on August 4, 2010 by Dan Jones Reports for the past week have been negative, and Red-eyed Vireos are migrating through now - just to complicate things!

Yellow-green Vireos are nearly impossible to locate after they quit singing (especially as the use of playback is not allowed here). Doug and Don Weidemann relocated the bird by checking each tree carefully according to their post to TEXBIRDS - and at some point the bird did start singing. Note especially the blurry face pattern in the first picture - and the full tail. When I saw this bird on August 22 the bird was in molt and the tail was but a stub - or I had a different bird; early reports were of two birds. The song is somewhat similar to a Red-eyed Vireo but more clipped and - dare I say it - House Sparrow-like. Listen a song on Xeno-canto here:

The use of playback is not allowed at this site as it is USFWS Lower Rio Grande NWR land. The use of playback is not allowed at most LRGV sites.

Wednesday, September 1, 2010

Bird Behavior - Plain Chachalaca

I was intrigued to watch this family group of Plain Chachalacas outside my new office at the Camp Thicket of Estero Llano Grande State Park and World Birding Center. This is the entire flock.

The two birds on the left picked up food and fed the small chick in front of them by picking up food (banana, milo, whatever) and holding it in the tip of their bill in front of the chick until ithe chick pecked at the food. The medium size bird on the right seems to be a juvenile - it has a narrow dull tail band and is much smaller in body size. It was also fed by the two larger birds.

In reading the Birds of North America [BNA] account for Plain Chachalaca online, they are not supposed to have more than one brood in a season - so according to that document, the two large birds here shouldn't be the parents of both the older juvenile and the young chick. The BNA states that Plain Chachalaca parents regurgitate food for their chicks, a behavior I have yet to see. Everyone can contribute to our knowledge of bird behavior in the LRGV by carefully observing birds and documenting what you see with photographs - even photos through a dirty window, (like these) help document your written observation. I'm going to try to chronicle some of my observations of bird behavior in the Lower Rio Grande Valley here.

The BNA is a wonderful series covering the breeding birds of the USA and is available online by subscription or in hard copy. The best thing about the online version is that the accounts are frequently updated. See for more information. Some LRGV specialties are not covered (e.g. Hook-billed Kite). Here in Texas, Texas Ornithological Society members can obtain access to the BNA accounts for a discounted price. American Ornithologists Union members have free access with their membership.

Wordless Wednesday - Pharr Purple Martin Roost