Sunday, December 6, 2015

The Water Witch and the Snakebird (The Pied-billed Grebe and Double-crested Cormorant)

(Picture: A Pied-billed Grebe wintering inside Steele Creek Municipal Park)
One of the strangest birds that I look forward to seeing during the migration of waterfowl in East Tennessee throughout winter is the Pied-billed Grebe (Podylimbus podiceps). It is a tiny, goose-like bird and is seldom seen flying. The reason is that it migrates at night. Instead, it paddles in lakes and rivers during the day, diving underwater quickly to escape predators. They can stay underwater for quite a while, only to pop up in another place that may be in dense cover. In more detail, the bird resembles a gosling more than an adult goose; their feathers are soft and downy for their whole lives. More grebes also flock to Tennessee; the Eared, Horned and Red-necked Grebe, but the Pied-billed is the only common resident, with the exception of the Red-necked Grebe spike of March 2014. But yes, the Pied-billed Grebe does breed and nest in Tennessee. The pair of birds call with monkey-like yodels and join in secluded marshes. There, they build a floating nest that they anchor in the water under the dense cover of cattails and sedges. After incubating the eggs, the parents carry their young atop their backs and will feed them their own feathers. But this charming bird, possessing names such as Carolina Dabchick, for its resemblance of a baby bird, and Dive-dapper or Dipper for its underwater swimming abilities, is also thought of as shy and secretive, earning it names such as Hell-diver, Devil-diver and Water Witch for its abilities to seemingly disappear while swimming. All in all, however, the tiny grebe is a harmless migrant bird that eats minnows, crayfish, dragonfly larvae and other small aquatic creatures.
(Picture: A glossy male water turkey flying over a reservoir in Northeast Tennessee.)
The Double-crested Cormorant (Phalacrocorax auritus), or "Shag" is a bird that's not all that well-known. It is falsely accused of damaging sport fisheries, though they impressively do eat some large game fish. They are large with shiny blue-black feathers and a bare yellow face, complete with beady blue eyes and two crests. Cormorants are large birds as well, earning them the name "Water Turkey". This bird is a member of the heron family, customarily nesting in rookeries with Great Blue Herons and Great Egrets. The young birds are often exposed to direct sunlight, so the parents will shield them with their wings. Also during the breeding season, the adults make deep grunting sounds which can startle one into thinking that they are confronted by a feral pig. Another name, "Snakebird", originated in its serpentine methods of swimming: only the cormorant's large neck is at the surface, while the body drags along underwater. They also have impressive deep dives. However, after several of these dives, the cormorant becomes waterlogged. You see, unlike the ducks that have waterproof feathers, the heron-related cormorant does not. Instead, the birds have to spread their wings like a sail and expose their body, sliding in slight breezes over lakes to sun and wind dry. This display is often seen, especially on cloudy days where little sun is present. Another very unusual habit of this bird is also commonly seen in vultures. They make roosts in a certain tree, and many adult birds flock there to sleep. After a while, the processed-fish droppings coat the leaves so badly that it kills the roost tree. The white marks from droppings, or "chalk", helps you locate a roost.

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