SEATTLE - Seattle City Light is testing a new device built by a local osprey expert to see whether it will protect the growing population of osprey along the Lower Duwamish River by keeping them away from high voltage power lines.
Last August, an osprey started building a nest on a Harbor Island utility pole and it caught fire.
"The fear is that if they came back and tried to nest, we could end up killing a bird," City Light Wildlife Biologist Ron Tressler said. "We're trying to keep osprey happy and off our structures, so we can coexist."
The utility turned to osprey expert Jim Kaiser, a consulting wildlife biologist who owns Osprey Solutions. Kaiser and Ed Schulz, a retired electrical engineer from Everett, built a nest deterrent system by modifying and updating a design originally conceived for transmission towers in the 1980s, and offered it to City Light for testing.
The osprey prefers to nest at the tallest available structures, which used to be dead trees or live trees with broken tops, but there aren't many of those in the Seattle area, Kaiser said.
“These birds have learned to select tall man-made structures like cell phone towers and utility poles,” he said.
Kaiser built a device that blocks the ospreys' access to power lines and makes it harder for the birds to place sticks and other nest materials on the pole. Using corrugated pipe that is wider than the 4-inch spread of on osprey's talons also makes it hard for the birds to grasp it and perch, Kaiser said.
Osprey have defeated many other designs, including plastic spikes, triangles and smaller diameter pipe coverings.
"We have yet to achieve state-of-the-art in osprey deterrence," Kaiser said. "We'll see how it goes."
Seattle City Light is committed to operating in an environmentally sensitive manner. A video shows some of City Light's earlier work to help osprey.
Protecting th esprey from power lines also reduces the risk of damage to the utility's equipment and an outage.