A tail-missing humpback whale spotted in the inland waters of Washington state likely lost its iconic flippers after becoming entangled, possibly in some kind of line or fishing gear, experts say. The loss of the fins, which are used for propulsion, appears to be a death sentence for the creature, which was last reported seen in late July.
Jessica Farrer, director of research at The Whale Museum on San Juan Island, Washington, was among those who responded to a July 23 sighting of the whale off the coast of a nearby island. As part of its work, the museum helps respond to reports of stranded or distressed marine mammals and educates boaters on the best methods for spotting whales. Farrer had seen injured humpbacks before, but never anything like this. She described the sight of the whale as heartbreaking.
The species was seen in the maze of inland waters between Washington State and British Columbia, the Salish Sea.
Since that day, no other sightings of the whale have been reported, she said.
“Everyone has an emotion when they see a humpback whale diving, and you see those huge fins that are over 15 feet (4.6 meters) wide, and here’s this whale, it’s just lost them. It’s like us losing our legs,” Farrer said.
Experts who were shared with photos and videos of the whale have concluded that the animal likely lost its fins through entanglement, she said. But it is not known what exactly it became entangled in.
One of the dangers humpbacks face is entanglement in fishing gear, such as mooring lines, pots and nets, according to NOAA Fisheries. Other threats include being struck or harassed by ships or boats and the potential impact of climate change on their food supply.
Evidence suggests that most humpbacks become entangled at some point, but are often able to free themselves, the agency said. The number of whales that die after becoming entangled is unclear.
There were 16 confirmed humpback entanglements off the coasts of Washington, Oregon and California last year, according to NOAA Fisheries statistics. The number of confirmed humpback entanglements surpassed 40 in 2016, a year in which a late Dungeness crab fishing season in California likely meant more fishing gear was in areas where the whales congregate, the agency said.
Justin Viezbicke, who helps with entanglement efforts and is the coordinator for NOAA Fisheries in California, said whales without fins are regularly seen along the West Coast, perhaps once a year or two. However, he said such situations are likely more common than they are seen.
Most recently, he said, rescuers off the coast of Southern California freed a humpback whale that had become entangled in fishing gear that was stuck in its flukes. Earlier this year, rescuers were able to free a humpback whale that had become entangled in fishing gear in a busy area near the port of Dutch Harbor, Alaska. NOAA Fisheries described that whale as “essentially tied up” and anchored to the line before it was cut free.
It’s unlikely a humpback whale could survive long without its flukes, said John Calambokidis, a research biologist with Cascadia Research Collective. He said one of the tragedies of entanglement is not just that animals die, but also how they die, which can be slow and involve suffering.
The actual number of entanglements could be much higher than the number of confirmed cases, he said.
In recent years, there have been increased efforts to find ways to reduce entanglement, he said. For example, California has made changes to the management of its commercial Dungeness crab fishery to protect whales from entanglement.
The humpback whale population on the U.S. West Coast is also growing and generally doing well, he said.
He contrasted that with the situation on the East Coast with entanglement of North Atlantic right whales. NOAA Fisheries calls the North Atlantic right whale one of the world’s most endangered large whale species and entanglement one of the greatest threats.