Dead Fin Whale And Dead Juvenile Humpback Wash Up On Unalaska's Shores
Two dead whales have washed up on Unalaska's shores in the past week: an adult fin whale — which is the second largest mammal in the world — and a juvenile humpback.
And while local biologists hoped to determine the cause of deaths of both whales, because of COVID-19, they likely won't be able to.
That's because it takes a large team of individuals to do a whale necropsy — or animal autopsy — which, in order to protect public health and adhere to social distancing requirements in the wake of the pandemic, just isn't possible, according to Melissa Good, the local marine advisory agent with Alaska Sea Grant.
"Human safety is always the number one priority," Good said. "Other places have difficulties with doing necropsies, whether the animal floats into a remote area or there's bears in the area — you're always putting human safety first and then going, 'okay, can we get a sample after that?' Right now, it happens to be that COVID-19 is at the forefront of all of our minds. And it's something that we all need to be cognizant about, and continue to protect ourselves and the community. So we just can't take those risks."
Unalaska typically sees about one dead whale wash up on its shores every year, according to Good. And when that happens, a team of biologists often perform a necropsy to determine the cause of its death.
But when the dead fin whale was discovered floating in the waters of Captains Bay near Westward Seafoods on Friday, and a juvenile humpback washed up on the shores of Unalaska Bay on Monday, Good said biologists were unable to do the necropsy because COVID-19 prevented a large enough team from coming together to perform the task.
However, with support from the Alaska Department of Fish and Game and NOAA Office of Law Enforcement, Good said she was able to collect skin, blubber, and muscle samples from both whales, as well as some fluid from the juvenile humpback's eye, to send to the state pathologist.
"We weren't able to do a full necropsy," she said. "I was able to take a tissue sample [of] skin and blubber, and we'll be able to look at the skin and get DNA work off of that, and you can get some toxins from the blubber. So we'll have a small bit of information on the whale."
Good said while the full necropsy wasn't possible, the biologists looked for signs of human interaction with both baleen whales that would indicate human involvement in their deaths. But, she said, they didn't see any fishing lines wrapped around them, or any obvious signs of scarring or cut marks due to an entanglement.
"We could have missed something because we couldn't see the whole body. But there wasn't really anything obvious right up front," Good said. "That certainly doesn't eliminate other human interactions like vessel strikes or anything like that. But we just weren't able to get that close of a picture of it."
The juvenile humpback did have a small five-inch rupture along its throat region, Good added. She said she's not sure if the rupture was caused by gas buildup as the whale decomposed, or whether it was caused by human interaction, like a vessel impact.
Although they chose not to in these cases, the Qawalangin Tribe often harvests meat and blubber from whales that wash up on shore, which Good said could have provided a great opportunity to get samples to see if Paralytic Shellfish Poisoning (PSP) or other toxins were a factor in the whales' deaths.
"We could have gone in with a very small team and possibly gotten some samples that could have been telling," she said. "I would have been really interested in fecal samples or urine or stomach samples to see if PSP was an issue in this case. That would have been some information we would have looked for and sought after, but we just didn't have that opportunity."
In July, Alaska state and local health officials started warning of dangerously high levels of toxins in shellfish, after a person died of PSP from mussels and snails in Unalaska. And, Good said, larger mammals like whales can die from ingesting algal toxins.
So, she said she would have some concerns with people harvesting these two whales for subsistence because they don't know when or how they died. And, she added, because they were unable to perform a necropsy, they probably never will.
And Good considered it a missed opportunity. While a dead humpback generally washes ashore once a year, she said she hasn't seen a dead fin whale in Unalaska since she took her position with Alaska Sea Grant six years ago. Although Unalaska is within their natural range, she said fin whales tend to stay offshore and don't generally come into the bay.
"Outside of COVID times, we could have flown in a very experienced veterinarian team that would really help us get down and make sure we're collecting the right samples," Good said. "And I know there's a lot of willing people here in the community that would step in and help out with the necropsies — the Qawalangin Tribe would certainly step in and help with that. And so we have the people here that can do it, and it's definitely a missed opportunity. But no matter what we do, human safety is always the number one priority."
Although this marks two dead whales that have washed up in Unalaska in the past week, Good said she can't speculate if the two deaths are related.
According to the state pathologist, they will process the samples from the two dead whales to confirm things like species and sex, but they will likely be unable do determine cause of death without a necropsy.