Tuesday, June 21, 2011

Hook-billed Kite Saga 2011

The date: May 28, 2011.
The location: Private property near La Joya, Texas.
The birds: Hook-billed Kites.
I live near the epicenter of Hook-billed Kites in the USA in western Hidalgo County, Texas. I actually go out looking for them in the summer, and I'm always surprised when I do find one.

My first observations of Hook-billed Kites this summer were of the adults carrying snails on May 29, 2011. The photo above is of the red-barred female. While small, whitish land snails in the genus Rabdotus are the common diet for the species, the kites don't usually carry them long distances unless they have a chick they are feeding in the nest. If they don't have chicks, they take the snail to a nearby stump or fence post, extract the snail, and grab another. But this female was carrying snails off to the north, and returning without a snail. She's got a chick somewhere north of me.

It's funny just how many people jump at the chance to burrow their way through thorny, dusty, tick and chigger-filled thorn forest to look for a Hook-billed Kite nest. A crack crew assembled to look for the nest on June 3. We were all around the nest but we didn't find it, though many of us gave blood to the thorn forest understory.

Here's the chick in the nest, as found on June 5, 2011. I found the nest, snapped this photo, and got out without the adults knowing I was present. That's a great feeling. The nest was actually visible from a road if you knew just where to look.

I worry about the kites being "loved to death" - they are very defensive of the area around their nest, and will follow people around if they find them too close to the nest. Instead of entertaining birders and photographers, they should be feeding their chick - no easy task in the current "exceptional" drought. The nest is in a mesquite, and if anything it is higher than the nest we found last year (see posts from June and July 2010). Here's the male, below, making a snail run - I'm not near the nest here, he's just flying overhead. The male Hook-billed Kite of this pair is a gray (normal) morph (as opposed to the rare black morph) but this individual is nearly lacking the white barring on the breast of a typical male. This unusual plumage allows this bird to be identified as an individual, especially with the very small number of Hook-billed Kites in Texas. The male makes many fewer trips to feed the chick than the female, at least in the second half of the nestling period. I've never found a nest in incubation or with a small chick. The male seems to feed the chick more than the female in the late afternoon. Here's the female Hook-billed Kite crabbing into a very strong headwind, and compensating for the wind by using her tail as a rudder. We've been getting a lot of strong winds this summer.
I wasn't so lucky trying to skulk into the nest to check on the chick a few days later. The female appeared behind me as soon as I got to the area. Hook-billed Kites often remind me of a parrot when perched, something like an African Gray. I think it's the light eye and the large head, but it is exascerbated when the bird is looking for a snail or cocking its head. After I peeked quickly at the chick - getting bigger, doing just fine - I headed straight out. The female was perched by the road on the way out, and she allowed me to walk right by her - but not without some comments. I think she's starting to recognize me as an individual. Probably better I don't know what names she's calling me. Here's the chick on June 18 - it's extensively barred on the underparts and already has the rufous collar across the back of the neck. The extent of the barring means it's a female, the males are much less barred as juveniles. The nest was empty on June 19. The birds vanished last year as soon as the chick fledged. They likely move the chick closer to the feeding area if it's not depleted, or to new areas if it is. I don't expect to see them again soon.

So just how rare are Hook-billed Kites? While they are widespread in the New World, extending well into South America, they are at their northern limits in South Texas. In South Texas there are very few birds, with 4 pair known in Hidalgo County this spring (2011). There were no territorial pairs in Cameron County where they are rare, and there were only infrequent observations in Starr County. The unique nesting habitat needs of the Hook-billed Kite includes stumps, snags, or fence posts to use as food perches, LOTS of accessible Rabdotus land snails for food, and tall trees to hold a nest. There aren't many places that have enough snails to support a nesting pair of Hook-billed Kites. The snails need natural areas with prickly-pear, yucca, or other plants that drop enough leaves, pads, and vegetation to form thick mats on the forest floor. When it gets hot and dry the snails burrow under the mats to conserve moisture.

Your best bet to see these birds is to check the Lower Rio Grande Valley Rare Bird Alert for recent sightings, or look from the tree tower at Santa Ana NWR or the Bentsen-Rio Grande Valley State Park hawk tower. Hook-billed Kites are often seen early in the morning when the Turkey Vultures are leaving their roosts. The Hook-billed Kites seem to start flying about the same time as the vultures. And remember, any day you see a Hook-billed Kite is a good day.

Observations of Hook-billed Kites in South Texas are greatly desired, please send information to rgvbirds@hotmail.com or enter them into eBird. Notes on plumage, color and extent of barring, and behavior (carrying snails, display flight, vocalizing) are of great interest. Notes on any Texas nesting attempts from years past are also desired.