Keep an eye out for ospreys
If you see a channel marker that appears to be wearing a large hat, it’s probably an osprey nest. Ospreys are among the easiest and most fun birds to watch because they nest in the open and are active all day.
“Most other birds of prey hide their nests from view, making them difficult to find, but ospreys nest right out in the open and are easily seen by folks on the reservoirs,” says Hill Henry, TVA biologist.
Because they feed almost exclusively on fish, ospreys prefer to nest where they have a clear view of the water. In addition to channel markers, they favor barge moorings, boathouses, bridges, and dead trees.
Like eagles, ospreys maintain the same nests from year to year, building and repairing them with large sticks. Unlike eagles, they rarely seek privacy, so you’re more likely to witness the construction of their nests and observe their daily routines.
Ospreys were once considered endangered, primarily due to the unregulated use of pesticides, but environmental laws and endangered species programs have restored the population throughout the United States.
TVA biologists report that 130 active osprey nests were recorded on Watts Bar Reservoir last year, which is the highest concentration of nests along the reservoir system.
“Watts Bar was the site of a very successful osprey reintroduction project performed many years ago by TVA and the Tennessee Wildlife Resources Agency,” Henry explains. “Their numbers continue to increase throughout the Tennessee Valley but are highest on Watts Bar and Kentucky reservoirs during spring and summer.”
Ospreys are very entertaining hunters, hovering 50 to 150 feet in the air and then plunging up to three feet into the water to capture a fish. Specialized talons and tiny impaling spikes on their footpads help the birds grasp their slippery catch. A hunting osprey always turns the fish forward, making the load more aerodynamic as the bird carries it back to the nest.
Two interesting behaviors distinguish ospreys from bald eagles, which also feed on fish. After pulling out a fish, ospreys fly up into the air, hover, and give a characteristic midair shake of their feathers to remove excess water. After eating, they often clean their feet by flying just above the surface while dragging their feet in the water.
The osprey has a short, hooked beak, white cap, dark-brown back and wings, and a white throat and breast. Females often have a prominent necklace of dark streaking across the upper portion of the breast area. The adult female’s wingspan averages five feet, the male’s about four feet.
Only the chicks and fledglings are hard to see. When the adults are away, young birds flatten themselves against the bottom of the nest.
“Watts Bar has numerous breeding pairs of osprey, usually with two or three young in the nest,” Henry says. “The adults are quite vocal and will circle your boat if they think you’re coming too close.”
The birds breed in warm weather, and migrate to warmer climes in winter.
“Our ospreys spend their winters along the southernmost portions of the Gulf Coast, Cuba, and South America,” Henry says.
Most chicks leave the nest by mid-July. But if you missed the show this year, Henry suggests checking the same location next spring. “Osprey pairs will come back to the same nest year after year, so you can expect a return engagement.”