Killer whales from Mexico are spotted off Oceanside; photos via ©Jonathan Hoover

Earlier this month, beachgoers in Tijuana enjoyed a rare sighting of killer whales just beyond the surf.

They were believed to be Eastern Tropical Pacific killer whales, or orcas, which rarely travel that far north.



Now, however, it seems as though the ETP killer whales are taking a liking to U.S. waters.



Eight killer whales were spotted Sunday off San Diego, and at least that many were spotted Monday and Tuesday off Oceanside, near the pier.

On Tuesday afternoon, killer whale researcher Alisa Schulman-Janiger matched two of the killer whales photographed Monday with killer whales photographed Sunday off San Diego.



“I just looked at additional images from the San Diego sighting Sunday, and from [Monday’s] Oceanside sighting; 2 of the 8 San Diego orcas match two of the Oceanside orcas!” the researcher stated on Facebook. “Hopefully the orcas seen off Oceanside this morning will continue to head up the coast!”



Orcas can be matched based on distinctive markings on their dorsal fins or saddle areas.



The images accompanying this post were captured Monday by Jonathan Hoover. The Oceanside pier is visible in the second image.



Not a lot is known about ETPs, versus transient orcas that occasionally visit Southern California waters from the Central California region. Schulman-Janiger said the ETPs are opportunistic feeders that will sometimes prey on other marine mammals. (The killer whales spotted off Tijuana killed a dolphin.)



The ETPs, which are more common off Central America and mainland Mexico, have been documented in U.S. waters, as far north as Catalina Island. But very few sightings have been documented over the past several decades.



NOAA has identified about 240 individual ETPs.



Their presence off Southern California comes toward the end of a summer-fall season that has been unlike any in recent history, in terms of rare visits by marine critters.



Wahoo, yellowfin tuna, mahi-mahi, and blue marlin are among species of fish that have been caught off Southern California, far north of their typical range.



False killer whales, Bryde’s whales, and pilot whales are among marine mammals that have been spotted in the region.



The odd catches and sightings were attributed to a band of unusually warm water that extended from southern Baja California to Southern California.