Least terns seek rooftop refuges

The least tern has turned to rooftops for nesting, adding new threats to the threatened species.

The tiny, whirling least tern is a spectacular bird on the fly. A wooing male will dart, dance and hover in the air with a fish in its mouth, then feed it to the female.

The gull-like shorebirds like to nest on the edges of flat, pebbly rookery islands and isolated beaches -- the kind of habitat that's disappearing along the developing coast. So more and more, they're nesting on the edge of flat, pebbly roofs near the water. That's a problem. The chicks can slip off the edge or be washed down the drain spout in a rain. The tar sticks to them.

And flat, pebbly roofs are disappearing too, replaced by more modern building standards and codes.

Wildlife biologists are trying to figure out if there's something they can do about it. The S.C. Department of Natural Resources is asking anyone who finds the terns on their roof to report it to the department as part of an ongoing count and study.

Least terns are considered a threatened species in the state. Like other shorebirds, they were nearly wiped out in the early 20th century when their feathers became prized for hats. Now, like a lot of other shorebirds, they're threatened simply because there are fewer and fewer places for them to nest.

Rookery islands like Crab Bank or Bird Key Stono are getting less and less isolated, and on top of that, the birds seem to be avoiding the islands that remain.

"They're one of the most imperiled shorebirds. They're getting squeezed from their natural areas by human disturbance and dogs and from the rooftops by building codes," said Nathan Dias, of the Cape Romain Bird Observatory.

A few birds were sighted on roofs in 1975. By the 1990s, seven of every 10 least terns sighted in DNR surveys were nested on roofs. "I think everybody was really surprised," said Felicia Sanders, DNR wildlife biologist. "But it's a large, flat, pebbly area where they feel safe."

DNR has attempted to lure the birds back to rookery islands by setting out decoys and other means. But so far, they seem to prefer the roofs. At the least, biologists would like to work with property owners to make rooftop nesting a little safer for the chicks and to keep people away, Sanders said.

Manatees headed our way

Water temperatures have hit 70 degrees -- the magic number for a magical creature to emerge.

Manatees will be making their summer appearance in the Lowcountry. Some 100 or more migrate from Florida to South Carolina, and many show up near dock water faucets in the Charleston Harbor area. They apparently like to drink the drip.

They have been spotted as far up the Cooper River as Tail Race Canal. Wildlife biologists are encouraging boaters to be careful, particularly coming in and out of docks. Boat propellers are considered the biggest threat to the slow-moving, ponderous marine mammals.

Manatees, or sea cows, can grow to 10 feet long and weigh a ton. They are bulbous, walrus-like sea mammals with bulldog snouts. Like other sea mammals, they surface to breathe. The Florida manatee is an endangered species. About 3,000 are known to exist.