OREGON STATE UNIVERSITY

Freeing Willy: OSU-led team uses novel cage to disentangle sea lion

04/02/2010

NEWPORT, Ore. – Less than one month after deploying a “capture cage” in an experimental effort to catch and rescue sea lions caught in man-made debris, a team led by Oregon State University used the floating enclosure to confine and free an adolescent California sea lion from a plastic packing band that had been caught around its neck for more than a year.

The animal had become a familiar sight in Newport since first being spotted in September 2008, with area residents and tourists often calling the OSU-based Marine Mammal Stranding Network in hope of seeing it freed. Locals nicknamed the animal “Willy” and often expressed dismay at the tight, white band that over time had cut through the animal’s skin and blubber and embedded itself into muscle tissue, said OSU’s Jim Rice, who coordinates the stranding network.

“The animal was coping with the problem well, despite the ugliness of the wound, but there was the potential that it could have caused systemic infection that might have killed him,” said Rice, who works out of OSU’s Hatfield Marine Science Center in Newport. “It was a very ugly wound.”

On Wednesday, however, the animal was spotted along with six other sea lions inside the capture cage. Dan Lewer, a Newport veterinarian; Jim Burke, director of husbandry at the Oregon Coast Aquarium; Rice and several others rushed to the cage in a skiff, where they were able to close its door, confining five of the animals inside.

Though initially alarmed, the animals soon quieted enough for the tangled animal to be lightly sedated, using a syringe affixed to a pole. Team members were then able to reach through the cage with a second pole device to cut and finally remove the band. A reversal agent was administered to counter the sedation, and the animal was back in the water shortly thereafter.

“As far as I know, this was the first use of a capture cage for this purpose, so it was very exciting,” said Rice, who will present findings on the cage work at a conference next week. “Most of the work I do, quite frankly, revolves around dead animals. So this has been a wonderful opportunity to actually help an animal in distress.”

The rescue comes less than two weeks after Rice and others successfully freed a Steller sea lion from a trawl net that had trapped it on coastal rocks inside the Sea Lion Caves in Florence. That rescue, the first ever performed at the caves, attracted national media attention.

Entanglements are a significant and growing problem, with hundreds of sea lions and seals thought to be caught in debris at any given time along the U.S. West Coast. Sightings of tangled animals have become increasingly common in coastal areas from San Francisco to Alaska, where humans are in close proximity to these marine mammals.

In early March, Rice and colleagues deployed the capture cage on the Newport bayfront at Dock 1, where coastal visitors frequently see the animals sunning themselves on the floating dock. Built by Mulder Sheet Metal, Inc., in Newport, the cage is a modified floating dock enclosed on four sides by a galvanized steel structure, with sliding doors on two sides. It is designed primarily to serve as an additional “haul out” area for sea lions to use freely, with its doors locked in the open position so animals can comfortably come and go as they choose.

This project has been the result of a collaborative partnership involving OSU’s Marine Mammal Institute, the Oregon Department of Fish and Wildlife, Oregon Coast Aquarium, the Animal Medical Care veterinary practice of Newport, and the Port of Newport, which provided the skiffs and allows the capture cage at its docks.. ODFW has used capture cages for years to study and monitor sea lion populations, and its cage design was used to model the cage now in use for disentanglement purposes.

Lewer and Steve Brown of the Animal Medical Care veterinary practice landed a grant to allow for the construction of the capture cage.

Disentanglement efforts have not had formal funding so the Marine Mammal Stranding Network is soliciting donations and sponsorship to enhance the project, including the purchase of a special Web camera for rescuers to continuously monitor the capture cage.

Donations for the project may be made to the Marine Mammal Stranding Fund at the OSU Foundation (800-354-7281). To make a gift online, go to http://bit.ly/aStaCr