There has been a startling number of killer whale sightings in the bay in June, normally an off-season month for whale watchers.
It happens rarely in Monterey Bay — perhaps a handful of times a decade at most.
Normally, the killer whales that frequent the area are familiar to marine biologists and others who track them.
So when a killer whale she didn’t recognize surfaced just 100 feet from a whale watching boat this past week, Nancy Black, a marine biologist and owner of Monterey Bay Whale Watch, was surprised.
The whale was accompanied by seven others that Ms. Black had never seen in the 30 years she has worked in the bay area.
“They were very active and social, exuberant and breaching,” Ms. Black said. “They kind of poked their head out of the water, curious of the boat. It was exciting for everyone on the boat to see.”
Researchers in California immediately contacted scientists farther north to verify the identities of these eight whales. They confirmed that seven of the whales in the pod were from the Pacific Northwest. Among them: a female with her daughter and two grandchildren, and another female with two kids. There was also a calf that none of the scientists had seen.
The sighting of the eight killer whales in Monterey Bay came during a month when there has been an unusual number of whale sightings in the bay. “We’ve seen about 35 different whales on nine different days this month,” Ms. Black said. “Normally, there would only be a couple sightings in all of June.”
But while it is normal for killer whales from California to migrate to the north and mix with the pods there, the northern pods almost never come down to the California coastline, she said.
A Monterey Bay Whale Watch photographer documented the pod of whales on Monday, the only day they were seen, as they hunted a porpoise and played in the bay.
More than 150 so-called transient killer whales frequent the California coastline, Ms. Black said, and she recognizes many of them.
“Some of the more frequent visitors are named Thumper, Ryan and Comet,” she said. “They look very distinct to someone who’s studied them. It’s like people’s faces. They have totally different marks, patterns and sometimes fin shapes.”
Not to be confused with the Southern Resident killer whales, which mainly eat amphipods and fish, transient killer whales feed on mammals, such as gray whale calves, sea lions and elephant seals. Several killer whales can binge on a single gray whale calf for days, Ms. Black said.
People are most likely to see killer whales around Monterey Bay in April and May, when their prey, the gray whales, are migrating through the area.
According to Ms. Black, the transient killer whales — including the eight from the Pacific Northwest — are most likely in the bay this late in the year because they are looking for food that never came.
Few gray whales had calves this year because they were not able to eat enough last summer, Ms. Black said. She said it was unclear whether this was because of gray whale overpopulation, melting ice caps or both.
Transient killer whales eat gray whales. Gray whales eat amphipods. Amphipods survive on algae. And this algae is found on ice. When the ice melts, Ms. Black explained, it disrupts the whole chain.
Researchers at the whale watching company saw killer whales feed on gray whale calves only twice during April and May. In some years, they witness up to 15 feedings.
“I hope it isn’t a trend, but it could be because you keep hearing reports of ice melting in the arctic,” Ms. Black said. “It does concern me.”
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