Satellite tagging program could have killed orca, say researchers

An improperly inserted tag may have caused .the death of a southern resident killer whale in B.C. waters this year, U.S. researchers have concluded.

A group of U.S. scientists released a report on Wednesday that concluded the orca died of a fungal infection, which may have been caused by the satellite tag.

L95 was part of the endangered southern resident population. The 20-year-old whale was found dead in Nootka Sound in March.

Several weeks earlier, the orca had been tagged by the U.S. National Oceanic and Atmospheric Administration (NOAA) with a satellite tracking dart while it was swimming off the Olympic Peninsula in Washington State.

Chief scientist Richard Merrick confirmed several factors related to the tagging may have contributed to the animal's death.

One possible factor was the tag fell in the water during an unsuccessful tagging attempt, and it was not sterilized properly before being used again.

"The proper protocol would have been to clean it with alcohol and with bleach, and I believe the bleach step did not happen, and that was just human error," said veterinary medical officer Deborah Fauquier.

In addition, after the tagging, broken parts of the the tag remained in the wound, which was located near significant blood vessels at the base of the dorsal fin.

Furthermore, the health of the whale at the time may also have been compromised at the time of the tagging, they said.

Still, they caution the their report is inconclusive, in part because of the state of decomposition of the orca when it was found.

"It's possible this whale could have had something else, some other sort of illness we couldn't determine," said Fauquier.

The researchers say, for now, the tagging program will remain suspended while experts review the effectiveness of the program and whether tagging is still useful for research.

They will also look at changing the way tagging is done on all marine mammals and examine the health of all seven other tagged killer whales.