The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Friday, May 05, 2006

Cross Timbers Wildlife News
The Bird With The Golden Slippers
Jim Dillard, Wildlife Biologist, Texas Parks and Wildlife Department, Mineral Wells

Although this title may sound like something right out of a James Bond movie or a children's storybook character, the "bird with the golden slippers" is alive and well here in Cross Timbers Country. You won't see them at the movies or in the library, but come spring, they'll return from their wintering grounds along the Texas coast and points south to grace our north Texas lakes, ponds and wetlands.

That wasn't the case between 1880 and 1910 in the United States when the future of the snowy egret (a.k.a. bird with the golden slippers) was uncertain. Their delicate nuptial plumes (aigrettes) were worth $32 an ounce which was more that twice the value of gold back then. They were a fashion statement and used to adorn ladies hats and bonnets. As a result, plume hunters along the Atlantic and Gulf of Mexico coasts dealt a devastating blow to their population and nearly wiped them out. Not only were adult birds killed, the resulting unattended nestlings also died. Only through the efforts of early conservation organizations and enactment of laws to protect them did the slaughter stop.

The snowy egret (Egretta thula) is one of a dozen species of herons in the Family Ardeidae found in Texas. The range of this partially migratory species extends from Chili and Argentina in South America to the northern United States and southern Canada. During the fall months, northern birds move south to the coast or into Mexico, Central and South America and the West Indies. Most snowy egrets nest in coastal regions but others venture northward during the spring to inland lakes and wetlands. Here in Northcentral Texas, I've found them nesting in numerous urban rookeries along with other colonial waterbirds such as cattle egrets, great egrets, little blue herons and black-crowned night herons.

Their snow-white feathers, long slender black bill, black legs and bright yellow feet (golden slippers) make identification easy. The bare patch of skin at the base of the bill (lores) and their eyes are also yellow. During the breeding season, foot coloration changes to a more reddish orange tone. Long, graceful aigrettes on their head, back and neck can be erected and displayed to greet and flirt with prospective mates or intimidate other egrets near their territory. Snowy egrets stand about two feet tall and have three foot wingspans. Their flight pattern is direct and buoyant with steady, fast wing beats. Body weight is somewhere around 12-13 ounces. They can live up to 17 years but most don't: the record is 22 years 10 months.

For most of the year, snowy egrets are silent. During the breeding season, however, they do a considerable amount of squawking and croaking around their nesting site or when quarreling with other birds. They'll also make a rattling sound by bill nibbling; gently opening and closing their bill to greet their mate and reduce aggressive behavior.

Snowy egrets wade in shallow water areas of salt and freshwater marshes, ponds, lakes and other wetlands searching for aquatic insects, shrimp, earthworms, crayfish, snails, small fish, frogs, toads, lizards, snakes and just about anything else that wiggles. They usually move about quickly with their wings slightly elevated and use their golden slippers to stir up the bottom to flush out anything in hiding and then grab it with jabs of their bill. Other strategies are to just stand still and wait for something to swim by or stick out one foot and vibrate it to startle prey. They'll also feed in fields and pastures on grasshoppers and small rodents or drop to the water from hovering flight on their prey - whatever works. Snowy egrets are often seen feeding with other heron or egret species.

During their spectacular courtship ritual, the beautiful lacy plumes are quickly raised and lowered to gain the attention of a mate. He'll point his bill to the sky and pump his head up and down, fly circles around the nest site and fly high in the air and then suddenly drop, all to demonstrate his prowess to the opposite sex and advertise his territory.

Snowy egrets are monogamous and raise only one brood per year. They nest along with other heron and egret species in large colonies. The male selects the nest site in a tree or shrub five to ten feet tall and brings nesting materials to his mate. Together they construct a flimsy platform nest where three to five pale blue-green eggs are laid. They both incubate the eggs for 20-24 days and then begin bringing food to the young. Egg hatching is asynchronous; consequently, the last of the young to hatch usually gets little food and starves. Young that do survive clamber around on limbs near the nest site and are fed by the parents for another month or so until they're able fly off and dance with their own golden slippers in the shallows.

I've conducted surveys on many rookeries here in Cross Timbers Country over the years to estimate how many birds were nesting there and which species were present. Some of those rookeries had 20-30,000 or more birds in them on about a half acre of land. Those were days I had serious reservations about by career choice as a wildlife biologist as I waded through several inches of "you know what" and was showered from above by irate birds with "you know what." Looking up was not an option. I quickly learned to count by the thousands: one-thousand, two-thousand, three- thousand.. finished! Rookeries sites are often used for many years and the resulting accumulation of "you know what" eventually kills the trees.

The snowy egret is one of the most elegant and graceful birds you'll ever see here in Cross Timbers Country. As with other species of wildlife, water and wet places on the landscape are fundamental components of their habitat. Without it, there'll be no birds with the golden slippers to see from a Cross Timbers Country road. Until next time - I'll see you down a Cross Timbers Country road and God Bless America!


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