Dead porpoises on Whidbey raise interest

Navy sonar use under suspicion

May 21, 2003 8:00 am
Volunteers with Whidbey Island Marine Mammal Stranding Network wrapped the body of a dead female porpoise in a shower curtain and weighted it with rocks and driftwood . Eagles scavenged the head of the porpoise before volunteers could haul the body up the bluff trail at Fort Casey State Park.Researchers in Seattle will try to determine cause of death
Volunteers with Whidbey Island Marine Mammal Stranding Network wrapped the body of a dead female porpoise in a shower curtain and weighted it with rocks and driftwood . Eagles scavenged the head of the porpoise before volunteers could haul the body up the bluff trail at Fort Casey State Park.Researchers in Seattle will try to determine cause of death

Marine researchers and environmentalists are wondering if dead marine mammals washing up on area beaches were killed by intense, mid-frequency sonar that was projected May 5 by the Navy guided missile destroyer USS Shoup into Haro Strait between San Juan and Vancouver islands.

The sonar waves from the Shoup were strong enough to be heard by people on whale watching boats who reported seeing porpoise, orcas and minke whales in the area acting strangely.

This incident comes as the U.S. House of Representatives is discussing a proposal to exempt the Department of Defense from the Marine Mammal Protection Act and Endangered Species Act. Critics argue that it could free the Navy to use sonar more often, regardless of its effects on whales and porpoises.

Since then, three dead harbor porpoises have washed up on Whidbey Island beaches: Fort Casey, West Beach and Greenbank.

A dead Dall’s porpoise has been reported on Fidalgo Island. A marine mammal’s body has been reported floating near Camano Island. And several dead marine mammals have come ashore in the San Juans.

Are these marine incidents related?

“Maybe none are,” Susan Berta of Orca Network said. “But it’s enough of a coincidence that we have to take a look.”

Thursday night, Brad Hanson, a researcher with Northwest Fisheries Center in Seattle, collected the harbor porpoise carcass from the beach at Admiralty Head in Fort Casey State Park. Volunteers with Whidbey Island Marine Mammal Stranding Network had secured the body after collecting data and taking digital photos. Sunday, May 18, researchers collected a harbor porpoise from Greenbank

The porpoise at Fort Casey State Park had no external signs of injury but was bleeding from the eye and blowhole.

Although eagles had scavenged the animal, Berta said necropsy tests could reveal possible causes of death from pressure trauma to pathology. “They’ll be looking for all types internal trauma plus pathogens, bacteria and parasites,” she said.

Berta said looking at biological contaminants is important because May 3, a cruise ship discharged 40 tons of raw sewage into Admiralty Inlet about four nautical miles off Whidbey Island.

Cmdr. Karen Sellers, public affairs officer for Navy Region Northwest, did not immediately return phone calls. However, in a statement Sellers stated that “neither visual lookouts nor the ship’s instruments detected the presence of marine mammals in the immediate area.” The sonar sweep ended when Canadian authorities reported complaints from small-boat operators.

Berta thinks Seattle researchers will finish testing all the collected dead animals within the month. Another dead harbor porpoise has been reported on West Beach but has not been found. Neither has a dead Dall’s porpoise around Fidalgo Island. Berta encourages people to report all marine mammal strandings.

“Even decomposed bodies have clues to cause of death,” she said.