While reports of gray whale strandings along the Pacific coast have jumped since 2019, there’s at least one place where these whales seem to be thriving. Hundreds of gray whales migrating from Mexico to their Arctic feeding grounds are stopping in Sitka along their route.
Sitka has always been home to charismatic megafauna like humpbacks and Steller’s sea lions, but over the past few years, a new marine all-star has emerged.
“We were just going to sit down there to go to shore and go walk the beach, and these two gray whales came right up to us.”
That’s Blain Anderson, captain of the sailboat Bob, describing an encounter with a gray whale just west of Sitka.
Gray whales have often visited Sitka, but over the past few years, boaters and biologists have seen an unusual increase in gray whale activity.
“I was just talking to somebody up in the parking lot who said at one point last year, he estimated over 700 whales – gray whales,” Anderson said.
Seven hundred might be on the high end, but whale biologist Lauren Wild says the number of gray whales in Sitka Sound used to hover around 10 or 20. Since 2019, it’s been closer to 150. As Wild put it, “it’s whale soup out here.”
Most of the news about gray whales in recent years has been pretty dismal. In May 2019, the National Oceanic and Atmospheric Administration (NOAA) declared an ongoing “unusual mortality event” due to elevated strandings of West-coast gray whales. Before that, a 2015-2016 marine heat wave, sometimes referred to as “the blob,” devastated Pacific-coast fauna from whales, to seabirds.
In Sitka, though?
“If people have been seeing them, they’re seeing whales rolling around and playing with each other,” Wild said. “They’re seeing a lot of feeding behavior, a lot of social behavior. Some people are seeing what looks like mating behavior.”
Like humpbacks, which are commonly seen in Sitka Sound, gray whales use baleen to feed. Unlike humpbacks, gray whales feed in the shallows, filtering silt and sand to get to tiny critters, like shrimp. Gray whales are smaller and often covered in parasitic barnacles and long scars from rolling around on the rocks.
Wild usually studies humpbacks and sperm whales, but the gray whale influx has piqued her interest. While it’s not entirely clear what is bringing this barnacle-covered baleen bonanza to the waters of Sitka Sound, Wild has a few ideas.
“We sort of wondered if the marine heatwave maybe disrupted some of the the reliability of food in the Bering Sea and Chukchi seas in the summer,” Wild said. “And if that possibly, sort of prompted these whales to be looking for more opportunistic places to forage along their migration routes, so they weren’t relying so much on those food sources.”
The food source? Likely herring eggs along the outer coast of Kruzof island.
“If you look at a map, the tip of Cape Edgecumbe is right along the outer coast,” Wild said. “If whales are migrating by and they just happen to be there at the right time, they might sort of start seeing more of that herring spawn, and it might pique their attention.”
Pacific herring spawn each spring in the waters around Sitka, and these fish – and their eggs – are an important food source for marine organisms and humans alike. Herring roe in Sitka is already a hotly contested resource, and now these motivated mysticetes may have joined the competition.
Wild said that the timing and location of gray whale sightings correspond to areas of herring spawn. She also pointed to observations from Alaska Department of Fish and Game spawn surveys:
“They’ll be diving and see gray whales around their dive boat and stuff,” Wild said. “So they’re certainly in the same area that those eggs are. And then they’ve seen a few times, you know, kelp beds that look sort of shredded like, and they’re imagining that is probably gray whales coming through and sucking up eggs off the kelp and rolling around in it.”
Wild hopes to confirm exactly these whales are eating – even if the fieldwork gets messy.
“Obviously you don’t know when they’re going to defecate,” Wild said. “So you kind of have to be at the right place at the right time. And we’ll use a little skim, almost like a fish pond net, that’s fine mesh, to just sort of scoop it up. You can also scoop it up with water in a Nalgene or something.”
Understanding what these whales eat is one part of the puzzle. Wild is also hoping to start building a catalog to identify and track individual whales to figure out which whales are coming to Sitka, and where else they’re going along their migration route.
In the meantime, both Wild and Anderson urge boaters to be cautious around gray whales, which may be more likely to approach humans than the average Sitka humpback. In Mexico, boaters can legally approach – and interact with – gray whales.
“They get chin scratches,” Anderson said. “And you know, I’ve seen pictures of people kissing them. And it’s something that perhaps they’ve gotten used to.”
The whales may ignore political borders, but Alaska boaters are still required to follow the Marine Mammal Protection Act – to avoid harassing whales, NOAA encourages boaters to stay 100 yards away and put engines into neutral if a whale approaches.
We don’t know what will happen in the future with these new visitors, or what the implications are for the West-Coast gray whale population as a whole, but for now, it seems that this struggling population has found a haven in Sitka feeding, socializing, and even – as Anderson has observed a few times – mating.
As Anderson noted, “It was all supposed to happen down to Mexico, but it does seem like they’re continuing their frisky ways up in – as we call it – romantic Sitka Sound.”
To report a stranded, injured, entangled, or dead marine mammal, call the NOAA Fisheries Alaska Statewide 24-hour Stranding Hotline: (877) 925-7773.