Brazos Bend

Last Brood of the Moorhens?

Common Moorhens may raise up to three broods per breeding season, especially in their southern range, but I was a bit surprised to find a pair of Moorhens with young chicks on the autumnal equinox, September 22, 2012. It got me thinking that these chicks, seen near the end of September, are most likely the last brood of the season at Brazos Bend State Park, Texas. Day-length, or photoperiod, along with temperature changes, govern many seasonal changes in animals including changes in the coloration of fur/feathers, hibernation, migration, and mating behavior. Here, along the gulf coast, our seasonal changes are gradual – permitting longer growing seasons and, happily, longer baby bird watching as well!

Common Moorhen with chick exhibiting begging behavior.
With their bald patches and what look like bad hair-plugs, Common Moorhen chicks could easily win a “so-ugly-they’re-cute” contest. This little one is begging for food by “flapping” its stubby wings.  Moorhens with young can be found throughout the long, hot summer at Brazos Bend State Park, Texas.

New Additions to Collections

Although being in the field regularly is always preferable, bad weather and the threat of bad weather have kept me indoors of late. Birding time has been transformed into computer time: additional images have been added to the Stalking the Hunters: Additional ImagesTexas Ducks, and Galveston Island Birds collections. Expect more in the near future.

Loggerhead Shrike with snake at Brazos Bend State Park, Texas.
This Loggerhead Shrike has just seized a snake. Shrike numbers increase significantly during the cooler months at Brazos Bend State Park. Shrikes, like other birds with black masks are challenging to photograph: the light has to be just right to capture a catchlight and a well-defined eyeball. Photo taken near water’s edge, Pilant lake.
Thermoregulating Great Blue Heron at Brazos Bend State Park, Texas
Thermoregulating Great Blue Heron? at Brazos Bend State Park, Texas. Herons and egrets can be seen occasionally in this sort of pose on hot, sunny days. It has been speculated that this is related to thermoregulation, but to my knowledge the details remain obscure. On the sweltering days when I see this sort of behavior, it would seem that warming up in the sun would be the last thing a bird would want to do–unless they are sterilizing parasites or pathogens thermally while employing gular fluttering or “panting” to keep their brains from frying. Photo taken at Pilant Lake.

 © 2012 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Instinctive Behavior in a Green Heron, Brazos Bend State Park, Texas

What a book a devil’s chaplain might write on the clumsy, wasteful, blundering, low, and horribly cruel work of nature! –Charles Darwin

Usually when one sees a wader grab a prey item, the prey is subdued, perhaps by a few pecks, then manipulated into position and swallowed. Today at Brazos Bend State Park, however, I observed a Green Heron grab a large American Bullfrog tadpole. The bird picked up and then dropped the tadpole a few times after intermittently pecking it. Finally the bird discarded the tadpole and walked away. I thought this strange given that waders of all species at Brazos Bend eagerly consume amphibians in all stages of development. Perhaps (although it seemed unlikely) the bird considered the tadpole to be too big to swallow?

I continued to watch the Green Heron fully expecting the bird to reconsider and return to the tadpole and eat it. Instead, it caught a juvenile frog and repeated the whole process! After pecking the poor frog a few times, the Green Heron just walked off without eating it. I have only seen this sort of thing once before when a Little Blue Heron captured and then discarded a crawfish. Do these waders hunt and kill (or at least maim) instinctively without being hungry, and without lardering the prey–just like well-fed house cats? If so, stone cold killers, these fellows!

Green Heron with juvenile frog at Brazos Bend State Park, Texas
Bad Day at Elm Lake: this Green Heron captured, subdued, beaked, and then discarded without eating this unfortunate frog. Canon EOS 7D/500mm f/4L IS (+1.4x TC). High-speed synchronized fill-flash.

©2012 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Declining Yellow-billed Cuckoos

The eastern subspecies of the Yellow-billed Cuckoo, like many birds of North America, is in decline due in part to habitat loss. This neotropical migrant was once common to abundant during summer in appropriate environments across much of its historical range (the eastern U.S., essentially from Texas to the Canadian border) but now has stable populations only over about 2% of that range.  A shy bird more often heard than seen, the Yellow-billed Cuckoo prefers forests near water with a mix of openings and thickly vegetated areas. We catch glimpses of Cuckoos from time to time, but getting a clear shot of one at close range is not an everyday occurrence.

Yellow-billed Cuckoo at Pilant Slough, Brazos Bend State Park, Texs
A cooperative Yellow-billed Cuckoo at Pilant Slough, Brazos Bend State Park, Texas

Summer Birding at Brazos Bend State Park, Texas

Many birders take the summer off in the Gulf Coast region. This is understandable given the low diversity of avian species relative to migration and the blistering sun, sweltering humidity and biting insects. Brazos Bend State Park, however, does offer some interesting possibilities in July through September if you’re willing to put up with a little pain. Family life of several species can easily be observed. At least two cohorts of juvenile Purple Gallinules, Common Moorhens, and Black-bellied Whistling-Ducks can be seen on Elm Lake during summer. In some places, the plants nearshore are literally alive with ducklings and baby rails. The first of the fall migrants also generally begin to show up in late July/early August as well. Even if you can’t get out there this summer, keep it in mind for next year–and don’t forget your hat!

Juvenile Purple Gallinule at Brazos Bend State Park, Texas
Juvenile Purple Gallinule: the huge feet of this young rail allow it walk easily across floating marsh vegetation. Photo taken at Elm Lake.

New Article and Collection: Stalking the Hunters

Stalking the Hunters: Observing and Photographing the Predatory Water Birds of Brazos Bend State Park, Texas explores the hunting activities of waders and other birds at one of the Texas Gulf Coast’s finest birding sites.

Little Blue Heron with American Bullfrog Tadpole at Brazos Bend State Park, Texas
This Little Blue Heron has just captured an American Bullfrog tadpole. Photo taken at 40-Acre Lake.