The endangered killer whale was found dead off the coast of British Columbia on March 30, a month after researchers tagged it with a satellite tracker the size of a 9-volt battery.

The adult male they called L95 had been healthy then, swimming with its pod just north of the Columbia River. But its corpse was emaciated. A closer inspection showed signs of a fungal infection.

A necropsy and an ensuing review released on Oct. 5 determined the exact cause of death, which could have a ripple effect on efforts to study the whales’ ecosystem and movements in the Pacific Ocean. The tracking dart provided a highway for the fungus to get into the whale’s bloodstream.

L95 was killed by scientists’ efforts to protect his species.

The review notes that the whale already had signs of a compromised immune system. Still, it says, “a fungal infection entered the animal’s bloodstream at the tagging site, and … this fungal infection contributed to the animal’s death.”

According to The Associated Press, the fungus may have been introduced by a contaminated tag. Or the two-inch darts on the prong may have brought fungi deeper when it struck near significant blood vessels. A first shot at the whale missed, and the tag fell into the sea, the AP reported. The darts may not have been properly sterilized when the tagger took aim again.

The satellite tagging program is suspended while the National Oceanic and Atmospheric Administration conducts its review, according to the AP.

“It’s devastating to think this could have happened,” Brad Hanson, the biologist who heads the orca tagging program, told the AP. He said he was in charge and “completely responsible” for not ensuring that the tag was properly sterilized.

“We’re trying to take stock of the report and comments and figure how best to move forward,” he said.

According to the NOAA, “the Southern Resident Killer Whale population is currently estimated at about 80 whales, a decline from its estimated historical level of about 200 during the late 1800s.”

L95’s death angered whale-protection activists who called the tagging program “barbaric and defective.”

“At least seven other satellite tagged whales are still carrying hardware embedded in their tissues from the attachment fixtures,” wrote Kenneth Balcomb, a senior scientist of the Center for Whale Research. He said the whale was named Nigel.

In my opinion, the tag attachment methodology was overly barbaric and defective from the get-go, and the entire tagging program should be rethought and evaluated for efficacy. The NOAA/NMFS tagging program is certainly injuring and disfiguring these Endangered icons of the Pacific Northwest.

The activists said scientists should use things such as underwater acoustic monitoring to track orcas.

Hanson noted the program has produced a tremendous amount of data about the whales in a relatively short period. The insights may lead regulators to expand habitat protections for orcas as far south as Northern California.

But in the wake of L95’s death, NOAA is considering new restrictions on tagging other whales and dolphins, not just orcas.

In February, researchers aboard the NOAA ship Bell M. Shimada were conducting a 20-day-survey to better determine where killer whales go during the summer, according to a blog post of the survey.

Three shifts used an array of methods to try to locate the whales. The boat towed an acoustic rig behind it, to monitor the sounds the orcas made. Crews on two decks watched for signs of whales blowing water out of their blow holes or breaching.

They stuck a dart into L95 on the third day of the journey, but it stopped transmitting a few days later.

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