Pedernales Falls State Park Prothonotary Warbler Nest Box Study: Mothers Day Morning Bird Blind

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.

Sunday, May 11, 2008

Mothers Day Morning Bird Blind

Most holidays I like to visit a favorite park to observe Nature. Today I visited the Bird Blind at the park. This blind is really a great place to see birds up close. It did not appear the park received the downpour that SW Austin did last night. So many of the birds were enjoying a bath this morning.

A small flock of warblers took advantage of the drip water baths and mister. There were 4 Yellow Warblers, a Wilson's and an Orange-crowned Warbler. I had the best look ever of an Ash-throated Flycatcher. I also saw my first Gray Catbird of the season. Three Lark Sparrows were the only sparrow species reported this morning. They have a striking facial pattern.

I later walked down to the river near the Falls. Soaring west along the river were two juvenile Red-tailed Hawks. One was carrying a Rock Squirrel in its talons. Back at the bird blind again I discovered this Pipevine Swallowtail Butterfly inside the blind and released it. Lucky for this species it is distasteful to birds.