Pedernales Falls State Park Prothonotary Warbler Nest Box Study: Lazy Summer Day & Breeding Birds

Prothonotary Warbler Occurrence In Texas

Central Texas draws the western line for the Prothonotary Warbler range. This species occupies much of eastern North America up to the southern boarder of Ontario Canada.
Prothonotarys' nest in natural cavities but also readily use nest boxes located on or near water. Flooded swamps represent ideal habitat but they will also nest along rivers or small bodies of water.
In May 2007 I saw a brightly colored male Prothonotary Warbler at Pedernales Falls State Park bird blind. After some research I learned male birds have been seen building nests in neighboring counties to Blanco County. Further research revealed a pair of Prothonotary Warblers successfully nested at Heard Wildlife Sanctuary in McKinney, Texas.
In December 2007 I decided to undertake a nest box study at the park. January through February 2008 I hiked the entire Pedernales River and tributaries within park boundaries, in an effort to choose the best sites. Habitat selection proved a challenge do to high flood levels along the river.
Five sights were eventually selected where two nest boxes each were placed. Most boxes were attached to trees however two were attached to metal poles. These boxes were monitored from March through June 2008 on a weekly basis. A Breeding Bird Study was conducted at each nestbox location in 2008 and will be continued in 2009.

Saturday, May 31, 2008

Lazy Summer Day & Breeding Birds

Six A.M. 67 degrees with overcast skies as I biked to East Park Boundary. I wish I camped overnight as it would have been perfect sleeping weather out here. The Common Nighthawks were doing their display dive.
Though many birds have fledged young, like the year round residents, there are a fair number of late migrants who are still on eggs or feeding nestlings at this time. I saw a Summer Tanager Thursday carry a large white grub away to the nest. Today I saw a female Golden-cheeked Warbler eating insects rather urgently. I believe she left the nest with eggs to fuel herself.

There are three vireo species nesting along the river: the White-eyed Vireo, Yellow-throated Vireo, and Red-eyed Vireo. The White-eyed Vireo arrived a couple weeks earlier than the other two species so one can see and hear many family groups moving around. The Yellow-throated Vireo really likes to hang out in the Bald Cypress trees along the river. Painted Bunting males on territory can be heard just about everywhere in the park, and Indigo Buntings can be found in lesser numbers along the river. The Blue Grosbeak female was adding her finishing touches to the nest I found on Thursday.
The Acadian Flycatcher finally made its appearance to the Tobacco Creek Seep half way through my survey there. It sang and made a twittering sound while flicking its wings. I believe this male

has a mate sitting on eggs somewhere. This individual has been sited here the entire month of May.
The flower photo is the Twisted Leaf Yucca which is blooming abundantly throughout the Hill Country right now. I added the second Yucca photo to show when the blooms fall off of the tall flowering stalk they get impaled on the pointed leaves below. At the end of every survey I settle down to writeup my field notes. When my last site is Hackenburg Creek I take advantage of the Bald Cypress shade along the river.