PHOTOS: Ospreys nest on crane, halting project

A pair of osprey have nested on a construction crane and halted construction in Anacostia Park. (Sarah L. Voisin/The Washington Post)

Biologists are exploring the possibility of building an elevated platform near the crane to serve as a nesting spot for the migratory birds when they return in future seasons. The 10-to-20 foot structure would have a box or basket on top capable of supporting a 200-pound nest.

In the mean time, work on the $50 million Anacostia Riverwalk Trail project has been suspended near the crane as the family apparently goes about caring for eggs in the nest. The chicks should hatch around the end of May and the parents will teach them how to fly.

“It takes quite a bit to raise an osprey — each chick requires 150 pounds of fish,” said Dan Rauch, a wildlife biologist with the D.C. Department of Environment.

The crane the ospreys have nested on. (Sarah L. Voisin/THE WASHINGTON POST)

Ospreys mate for life and the six known pairs in the District have found some interesting places to live. One pair nests on a mast-like structure on the U.S.S. Barry, a decommissioned Navy destroyer on display in the Navy Yard. Another pair have set up shop on a piling beneath the Frederick Douglass Bridge. Bird lovers can watch a nest cam of the family.

Another set was recently discovered at the Kenilworth Park and Aquatic Gardens, while others nest on channel markers.

Rauch said the osprey has made a comeback in recent decades after populations were decimated by DDT in the 1950s. The pesticide thinned the shells of the bird’s eggs and caused them to break.

A report in the Journal of Wildlife Management found just 233 pairs of ospreys in the mid-Atlantic in 1975. Today, Rauch said there about 6,000 pairs in the area.

“People ask, ‘Why stop a project for an osprey?’” Rauch said. “They are a top predator, like tigers in India. Their health is indicative of the health of the entire eco-system.”

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