The Nature Writers of Texas

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

Friday, June 02, 2006

Cross Timbers News
A Little Bit Blue
Jim Dillard, Wildlife Biologist, Texas Parks and Wildlife Department, Mineral Wells

I’ve been a little bit blue lately as I contemplate retirement after working 40 years as a wildlife biologist with Texas Parks and Wildlife. The miles are beginning to catch up with me. The thrill of spotlighting deer from the back of a bouncing pickup truck after midnight on some remote, rough Cross Timbers backroad isn’t nearly as much fun as it used to be. Be that as it may, I’ll always enjoy observing wildlife around me whether I’m at the beach or in my own backyard.

Like the other evening as I sat out under my favorite shade tree in the backyard reflecting on some past experience, a little blue heron quietly and gracefully floated overhead, flying north to roost somewhere for the night. I hadn’t seen one since last October when they moved out to spend the winter down along the Texas coast. Within a few weeks it will be busying itself with nesting and trying to raise more little blues in a rookery along with several other species of colonial waterbirds.

The little blue heron (Egretta caerulea) fared better than other heron and egret species during the market hunting days around the turn of the century when feathers in ladies hats was the craze. Since little blues didn’t have white feathers or long, showy aigrettes, they weren’t in the crosshairs of the plume hunters.

The little blue heron ranges from the Atlantic and Gulf states to the interior of the eastern United States. After the breeding season, birds wander widely throughout the eastern two-thirds of the country and as far north as Canada before heading south for the winter. In Texas, they nest primarily in the eastern one-third of the state and winter along the Gulf coast. Here in Cross Timbers Country, they’re commonly seen around area lakes and wetlands or nesting in rookeries with cattle egrets, snowy egrets, great egrets and black-crowned night herons. In these large aggregations of nesting birds, little blues tend to nest on the periphery of the colonies somewhat away from all the hustle and bustle. They may also nest in small colonies with only their own kind.

Their plumage is dull slate-blue except on their neck and head where it’s maroon: sexes are similar. Legs and feet are dark bluish-green and eyes yellow. Their long slender gray bill bends slightly downward and is black tipped. They stand about two feet tall, have a 40 inch wingspan and weigh less than a pound. Young little blues are white and are often confused with snowy egrets since they don’t take on adult plumage until their second spring. In molt transition, their coloration appears mottled with a combination of bluish and white feathers. They’re usually quiet, but at the nest site they make considerable racket squawking, clucking or croaking.

Little blues prefer freshwater over saltwater areas where they wade in the shallows or along shorelines searching for crayfish, small fish, crabs, aquatic insects, tadpoles, frogs, turtles, spiders, snakes and other crustaceans. On land, they’ll feed in open fields on lizards, small rodents, grasshoppers and other insects. I once found a florescent orange plastic fishing worm under a little blue heron nest that apparently failed to pass the taste test of a nestling. They’ll also follow farm tractors cultivating fields to feed on exposed insect larvae, worms and small rodents. Over in Louisiana and Southeast Texas where they’re often seen feeding along the dikes and levees of rice fields, they’re called “levee walkers.” Other common names are blue cranes or little blue cranes.

Courtship may involve a variety of nuptial displays including neck-stretching and bill-snapping by the male, mutual nibbling of each other’s feathers and crossing or intertwining necks. Males also display in their territory to discourage other suitors from getting too close to their little blue darling.

As with other heron and egret species, their nest is a flimsy see-through platform of sticks and twigs with a slight depression in the middle. It’s built by both parents in only three to five days during April or early May in a tree or shrub 3-15 feet above ground or water. During wind storms, eggs are often blown from nests and crack on the ground.

The female will lay three to five light blue eggs that they both incubated for 20-23 days. Egg shells are discarded from the nest as soon as the young are hatched. Eggs hatch over about a five day period and hatchlings are then fed regurgitant by both parents for two to three more weeks. Young will then begin to climb around on limbs near the nest. At four weeks they can make short flights and by six or seven, they’re off to fend for themselves.

Little blue herons are very shy and hard to get close to. They’ll feed in small groups with other heron species, often walking slowly through shallow water or standing still waiting for something to move. Prey is caught with a quick jab of their bill and then swallowed whole. When in flight or resting, their neck is held in an “S” shaped curve.

My theory is that our population of little blue herons has increased during recent years, largely due to the expansion of the breeding range of cattle egrets. Where they’ve established nesting colonies, little blue herons and several other species of herons and egrets have followed. Consequently, the skies here in Cross Timbers Country are a little bit bluer these days than they used to be. Until next time, I’ll see you down a Cross Timbers country road and God Bless America!

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