More orcas than usual this time of year are being spied increasingly in San Diego’s coastal waters.

And it’s the job of Alisa Schulman-Janiger, lead research biologist for the California Killer Whale Project (californiakillerwhaleproject.org), and her team, to figure out why this is happening, and what it all means.

“Over the last 40 years, we’ve never had anything like this, where you’ve had orcas sticking around together (hunting) for a month or longer,” said Schulman-Janiger, who’s spent years tracking orcas and studying their behavior.

She added their most recent high-profile presence in San Diego’s water is due in part to this particular species of killer whales being of the more “boat-curious” type. She added this particular orca pod they’ve been studying has been seen approaching boats and “turning on their sides to look at people,” noting this has “added a special glow to the encounters making them super special.”

One clue as to why these orcas are here now in greater numbers may have come in the form of an endangered fin whale found washed up near Pacific Beach on Dec. 10. Originally, biologists thought wounds found on that fin whale were from sharks, as they could find no signs of ship strikes or propeller wounds. However, it was later determined that the non-fatal wounds found on the fin whale’s body were more likely caused by killer whales, according to Michael Milstein of the National Oceanic and Atmospheric Administration (NOAA).

“It’s hard for us to know (for sure),” said Schulman-Janiger about the reason for the whales increased presence in San Diego waters, while pointing out the answer might be found following the food chain. “This group of killer whales came from Mexico,” she said noting the marine mammals feed “wherever food is abundant. But we can’t possibly know why they decided to go on a ‘road trip.’ Perhaps these are (just) more adventurous whales that are more curious,” she said.

Noting orca pods can be comprised of one or more families, Schulman-Janiger said they know this particular pod has two nursing mothers with young calves, which translates into their needing to eat more to survive. She added the orca pod being studied was found in the area where the fin whale “with fresh-bleeding tooth bites” was beached just 24 hours later. “This group of killer whales could likely have been the ones that wounded that fin whale causing it to beach and later die,” Schulman-Janiger concluded.

The wildlife biologist pointed out killer whales, and their prey, are sensitive to changes in water temperature, which may also account for the orcas being present in the now warmer-than-usual waters. “El Ninos (warmer-than-average sea surface temperature events) used to happen every 5-8 years, but are happening closer together now, with shorter intervals in between,” Schulman-Janiger said. She added that another weather phenomenon known as “The Blob,” could explain why killer whales and their prey are ending up in San Diego waters more now this time of year.

The Blob is a large mass of relatively warm water in the Pacific Ocean off the coast of North America that was first detected in late 2013 and continued to spread throughout 2014 and 2015. An example of a marine heatwave is ocean water temperatures with The Blob can be between 4 and 10 degrees above average.

“During The Blob in 2014, we had waters several degrees above normal up and down the Pacific Coast from Mexico into California and we saw an uptick in birds, fish, and killer whales coming from Mexico into California waters,” said Schulman-Janiger. “That leads us to believe this change may be tied to the warming of the waters. That isn’t necessarily global warming. But it’s definitely climate change.”

Schulman-Janiger noted the dolphins may be coming here more now because of climate change as “they know San Diego is a good place (to feed).” Consequently, she surmised, killer whales may be following them to their new feeding grounds.

ORCAS

The orca (Orcinus orca), or killer whale, sometimes referred to as the “wolves of the sea,” are toothed whales and the largest members of the oceanic dolphin family. Recognizable by their black-and-white patterned body, orcas are found in diverse marine environments, from Arctic to Antarctic regions to tropical seas.

Orcas are apex predators with a diverse diet often specializing in particular types of prey including a variety of fish, sharks, rays, and marine mammals such as seals, other species of dolphins, and whales.

Killer whales are highly social. Some populations are composed of highly stable matrilineal family groups (pods). Their sophisticated hunting techniques and vocal behaviors are passed along from generation to generation.

Orcas are not usually a threat to humans, and no fatal attack has ever been documented in their natural habitat. There have been cases of captive orcas killing or injuring their handlers at marine theme parks.