Winging It

 

While most of us have seen birds splashing in water to find relief during hot weather, other cooling techniques are available to them. Lifting or spreading their wings, allowing the flow of air across unfeathered or less-feathered body parts, also helps to dissipate the heat of summer.

Because I’ve usually been at work and without a camera at hand when I’ve seen great blue herons engaging in the behavior, I was especially pleased to find this pied-billed grebe with raised wings at the Brazoria Wildflife Refuge near the end of July.

Despite their reputation for being a bit skittish and camera-shy, this grebe continued its behavior for nearly fifteen minutes. Raising and lowering its wings in a slow, repetitive pattern allowed body heat to escape, and keeping its wings raised for as much as a minute at a time might have caught a bit of breeze as well.

 

Comments always are welcome.

Home, Sweet Nest

Nesting black-necked stilt (Himantopus mexicanus) ~ Brazoria Wildlife Refuge

Whether calling in flight, searching for food, or patrolling their territory on long, improbable legs, black-necked stilts always bring a smile. Their delicate, even fragile appearance is belied by their preferred habitats: fresh and saline marshes, mudflats, flooded agricultural fields, ponds, and drainage ditches.

During their mating season, which lasts from April through August, they construct ground nests near water, adding sticks, mud, grass, or shells to simple scrapes in the ground.

Both parents incubate three or four tan-colored eggs for 22-26 days; females often incubate by night, while both sexes take turns by day. Because even birds have to cope with the heat, on very hot days the parents will go to the water to wet their belly feathers before returning to the nest to cool the eggs.

After hatching, chicks run, walk, and swim as soon as their down has dried: usually within twenty-four hours. Their parents remove any tell-tale eggshells from the nest, and the chicks begin hiding in the water at night; both actions help to prevent predation by disguising their scent.

Nesting Pied-billed grebe (Podilymbus podiceps) ~ Brazoria Wildlife Refuge

Like the stilt, pied-billed grebes forgo trees for nesting purposes, but they prefer water instead of land. Shallow water will do, but depths greater than nine inches are best, since they allow the bird to approach or escape the nest underwater.

Usually found singly or in pairs around ponds and saltwater marshes, pied-billed grebes tend to dive at the slightest provocation, but they also possess the ability to squeeze air from their feathers and sink beneath the water’s surface without leaving so much as a ripple. Once underwater, they can stay submerged for some time,  swimming great distances to the safety of the reeds, or they can remain just below the surface, with only their eyes or nostrils visible.

Their tremendous swimming skills have a downside, of course. Barely able to walk on land, the grebes prefer to dive and swim when they sense danger, instead of flying to escape.

The water that protects them also facilitates construction of their nest platform: a dense mass of plant material that either floats or is anchored to standing vegetation, like the stems of bulrushes and water lilies. Both male and female participate in selecting the site and building the platform and nest, a bowl-like structure four to five inches in diameter and about an inch deep.

Eventually, both also join in incubating four to seven eggs for about twenty-three days, covering the eggs with nest material when they leave to feed. The young are able to swim almost immediately upon hatching, although I was surprised to learn that they sometimes ride on their parents’ backs like loons; adult pied-billed grebes have been known to swim underwater with their chicks on their backs. 

Ground-nesting birds are quite common, of course, but the black-necked stilt and pied-billed grebe are remarkably public about their nesting process. The next time I glimpse a nice, round clump of floating vegetation, or see a stilt just sitting around, I’ll take a closer look. There might be a new family waiting beneath the wings.

 

Comments always are welcome.