Approval has been given for a controversial plan to satellite tag an endangered species of killer whale that plies the waters off the Pacific Coast. Researchers hope the tracking devices will reveal the orcas’ activities during the winter, but another expert said the tagging could harm the vulnerable whales. Killer whales are one of the most studied marine mammal species in the world, yet very little is known about where they go and what they eat during the winter months. Brad Hanson, a wildlife biologist at the National Ocean and Atmospheric Administration, or NOAA, has U.S. government approval to attach the tiny tracking devices to the dorsal fins of six whales per season. “We’re trying to get better information about what they’re doing during the winter. This is a period of time where a number of animals seem to disappear from the population,” Mr. Hanson said in an interview. “Trying to better understand what the risk factors during the winter are would potentially help management biologists … make sure we have what’s necessary to meet the recovery goals that are in the recovery plan.”
But Ken Balcomb, a senior scientist at the Center for Whale Research in Friday Harbour, Wash., has seen other killer whales that were tagged off Alaska and is concerned. “They’re heavy-duty barbs, and the only way (the tag) comes off is tearing away flesh and leaving a golf-ball sized hole.”… Mr. Balcomb, who’s been studying southern residents for decades, said his concern is the barbs could cause an internal infection, like the minor puncture wound that killed a 20-year-old resident whale a few years ago. “Because these whales live in an urban environment that has a lot of toxins and a lot of problems for their immune and reproductive system, they’re especially susceptible to these injuries.” Mr. Hanson has tagged more than 250 whales from 15 different species and said there has been no adverse impacts connected to survival.
The tag is about the size of a nine-volt battery and it would be shot from a cross bow or pneumatic gun into the dorsal fin. The tags can remain attached anywhere from three to nine weeks until they fall out, leaving the wound to heal on its own, Mr. Hanson said…The transmitter could last about six straight weeks, but in order to stretch out the life cycle, they would turn off and on the transmitter, he said.
Terri Theodore, Experts get approval to satellite tag endangered killer whales in the Pacific, the Globe and Mail (Canada), Jan. 22, 2012