A federal program that uses satellite transmitters to track killer whale movements has been suspended after pieces of a metal dart associated with a transmitter were found embedded in the fin of an orca discovered dead two weeks ago in British Columbia.
The whale, L-95, a 20-year-old male named “Nigel,” was found dead floating near Nootka Island along the west coast of Vancouver Island. He was the same whale who was tracked for three days off the Washington Coast by researchers with NOAA’s Northwest Fisheries Science Center after they attached a satellite transmitter on Feb. 23.
The attachment, which involves the use of a dart with sharp metal prongs, was routine in every way and has not been directly implicated in the death of the animal, according to a statement from NOAA officials.
Still, finding pieces of metal still embedded in the dorsal fin of the whale has already sparked a reaction from opponents of the darting procedure, including Ken Balcomb of the Center for Whale Research on San Juan Island. I expect further expressions of sadness and anger from others over the coming days.
“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,” Ken said in a prepared statement.
“The NOAA/NMFS tagging program is certainly injuring and disfiguring these endangered icons of the Pacific Northwest, and it is my subjective opinion that it is adversely altering their behavior toward benign vessel interactions to approach them for photo-identification,” he said.
Ken noted that the cause of L-95’s death has not been determined, so the relationship to tagging could be coincidental, but two transient killer whales also went missing after tags were attached. Those deaths could be coincidental as well, he added, but other tagged whales are still carrying around pieces of embedded darts.
The 20-year-old male orca was found dead and in an advanced state of decay on March 30 by researchers from Canada’s Department of Fisheries and Oceans. A necropsy revealed “fair to moderate body condition” and no clear sign of death. See the DFO news release for a few other details.
Although there was no sign of infection where the satellite tag pierced the dorsal fin, “veterinarians are investigating whether the tag attachment penetration sites may have provided a pathway for infection,” according to the NOAA statement. “Additional tests are underway to determine presence of disease agents such as viruses or bacteria that will provide further details as to the cause of death.”
When the satellite transmitter was first attached, the researchers “noted the outline of the ribs were slightly visible on several members of L pod, including L95, but observed nothing suggesting a change in health status.”
The satellite tracked L-95 for three days and then stopped. Researchers assumed the transmitter had fallen off, but they were not able to meet up with the whales before the research trip ended.
Expressing extreme sadness, agency officials say they are concerned that parts of the dart were found imbedded in the fin.
“These tag attachments are designed to fully detach and leave nothing behind,” says the NOAA statement. “Of 533 deployments, only 1 percent are known to have left part of the dart in the animal upon detachment, although several of these have been in killer whales.
“The team has halted tagging activities until a full reassessment of the tag design and deployment is completed to reduce risk of this happening again.”
Ken Balcomb recalled that he had complained about the tagging program several years ago as officials were debating whether the endangered Southern Resident population should become involved. Ken says he was assured that previous problems had been fixed and that he should simply document any problems he sees.
I remember the controversy well, as NOAA researchers were convinced that the data gathered would be worth what they considered an insignificant amount of risk. Check out “Orca tagging raises questions about research” from Dec. 8, 2010, and “Orca researchers divided over use of satellite tags” from Dec. 28, 2010.
“Clearly with L95 still retaining tag hardware in his wound site, the hardware attachment issues have not been fixed,” Ken says in his latest statement. “I suggest evaluating the cost efficiency and data already gathered from sighting reports, photo-ID, and tagging to determine whether any additional studies of SRKW distribution are justified.”
The tracking studies have been used the past few years to document not just the areas where the killer whales travel but also areas where they linger and forage for food.
NOAA’s explanation of the tagging program, its benefits and potential changes to the “critical habitat” protections for the killer whales are outlined in a question-and-answer format, including specifics about the death of Nigel, L-95.
Meanwhile, a young female orca, estimated to be two weeks old, has been identified as a Southern Resident by DFO scientists. Cause of death was not determined, but it was likely that the animal died from birth complications, officials said. The calf was found March 23 near Sooke, B.C.
Analysis of blood and tissue samples are expected in three to four weeks for both the calf and L-95, according to the DFO statement.