Pacific Northwest marine biologists had some grim news on Friday, as at least one more orca death was confirmed in the Puget Sound area in Washington state, further gutting a killer whale population that is edging toward historically low levels.
According to the Seattle Times, a mother whale codenamed J28 had gradually become sicker over the past several months, before vanishing from her “J-Pod” family group on or around October 19. She was about 24-years-old at the time, an age normally considered ideal for breeding, and was instantly recognizable due to a nick on her dorsal fin. Her carcass has yet to be spotted by whale watchers, but the orca may have died in the Strait of Juan de Fuca sometime last week.
An obituary for J28 written by Center for Whale Research director Ken Balcomb was published by the West Seattle Blog, and details the specifics of what may have led to her death.
“J28 was noted to be losing body condition in January 2016, presumably from birthing complications, and by July was clearly emaciated. If her carcass is ever found an examination of her ovaries may reveal how many ovulations/pregnancies she actually had, as well as her proximate cause of death (probably septicemia).”
The Seattle Times report quoted Orca Network spokesman Howard Garrett, who believes the death of J28 may have also led to the death of her 10-month-old calf, codenamed J53. He said that the calf was still in the nursing stage, and that his 7-year-old sister, J46, went through a “heroic effort” to save him and their mother.
Garrett also observed nicks and scratches on J53’s skin, which had most probably been a result of his sister and aunt trying to keep him on the surface by using their mouths to hold on to him. He believes J53 may have already been in a state of malnourishment, as the calf’s mother may not have had enough milk to feed him with “for quite a while.”
Balcomb’s documentation of the mother orca’s death included some passages on the steps J46 took to care for her relatives.
“(J53’s) sister, J46, had been catching and offering salmon to her mother and little brother for several months while mom was ill, but that was simply not enough nutrition provided to three whales by one little female no matter how hard she tried.”
All in all, there are only about 80 orcas following the death of J28 and the uncertain fate of J53. Balcomb says that’s close to the lowest population counts in decades, which is a big concern considering the lack of population growth in the two decades preceding the current decline.
Southern resident killer whales can be found in Puget Sound, the Strait of Juan de Fuca, and in the vicinity of the San Juan Islands, the Seattle Times wrote. The animals were classified as an endangered species in 2005, as a result of a sharp downtick in population count from about 100 whales in the late-1990s to approximately 80 in 2001. Despite a mild increase in killer whale count in the years that followed, their numbers were back down to about 80 as of 2014.
Following that decline, nine calves were born between December 2014 and January 2016, with J53 being among the more recent births. But that positive development was negated by seven deaths, including three calves (J53 presumably included), and four adults, with J28 being the latest casualty.
In a report from KOMO News, Balcomb said that that certain measures need to be taken in order to prevent further orca deaths and to ensure existing populations receive enough food. And that may be facilitated by breaching four dams on the Lower Snake River in order to allow enough salmon availability for the surviving killer whales.
[Featured Image by NOAA Northwest Fisheries Science Center/AP Images]