Another subpopulation of killer whales appears to use specialized hunting techniques to hunt the marine mammals they eat. Killer whales, or killer whales, are the ultimate apex predators and have been observed attacking great white sharks, porpoises, and even blue whales. They live in every ocean on Earth, and the particular environment they live in greatly shapes their particular food preferences. Killer whales foraging near deep underwater canyons off the coast of California may be using the sloping ocean landscape to teach them how to catch food. Regarding these survey results, The study was published March 20 in an open access journal Pro Swan.
Resident vs Temporary Resident
Orca pods can form different populations and ecotypes. They have their own social structure, food preferences, and hunting techniques. resident orcasthree endangered pods that spend the summer and fall months in and around Puget Sound near Seattle, Washington, feed exclusively on salmon and have a more rounded dorsal fin.
[Related: Orca observed hunting and killing a great white shark by itself for the first time.]
Another type of killer whale is temporary killer whale We specialize in hunting marine mammals. Temporary killer whales are typically slightly larger than resident killer whales and have more pointed dorsal fins.
The ephemeral organisms that forage in the North Pacific can be further divided into two groups. Inner coast whales feed in shallow coastal waters, while outer coast whales hunt in deeper waters. Most studies have focused on killer whales that hunt close to shore, and less is known about the foraging techniques of more offshore whales, such as near-shore whales. monterey submarine canyon In California.
“Monterey Bay provides a suitable environment to investigate ephemeral foraging ecology and behavior because it has a large, deep underwater canyon system near shore that is accessible to researchers.” said the author, a marine ecologist at the University of British Columbia. Josh McInnes To tell pop science.
Two different foraging behaviors
McInnes and his team observed transient killer whales on the outer coast foraging around the ocean floor in one of the deepest Monterey canyons in the United States.They are Data collected and analyzed The findings come from marine mammal surveys conducted from 2006 to 2018 and whale watching ecotours conducted from 2014 to 2021. The whales primarily ate California sea lions, gray whale pups, and northern elephant seals.
Killer whales were observed using two distinct foraging behaviors that appear to be unique to these more offshore transients. When foraging in the open sea, groups dispersed to search for marine mammals to feed on on their own. Each whale surfaces at a different time.
However, as pods of whales scan deep underwater canyons and shelf breaks, they follow the contours of the canyon in search of prey. Groups will also emerge at the same time.
Both foraging behaviors appear to be unique to these whales compared to other ephemeral groups that hunt in shallow waters, McInnes said.
[Related: Raising male offspring comes at a high price for orca mothers.]
“Based on our focus-tracking studies, their ability to find and track canyon contours was remarkable,” McInnes said. “We hypothesize that killer whales that temporarily hunt in underwater canyons may be listening to the sound of upwelling water along continental slopes and shelf breaks.”
Ramming or poking a sea lion
Killer whales use special techniques when they cannot easily corner prey in open waters. They subdued their prey by ramming their heads or bodies, as some killer whales do with boats. Whales also used their powerful tails to attack and launch sea lions into the water and into the air.
McInnes and his team found that these outer-coast whales different subpopulations It is in these deep-sea habitats that they developed these hunting techniques. It is also possible that these foraging behaviors are culturally passed down from generation to generation. The researchers were surprised by their affinity for moving along canyon slopes and shelf breaks, and how much time they spent foraging and foraging.
“The transient killer whales of California’s Monterey Bay spend 84 percent of their daylight hours foraging (searching, tracking, and feeding), which is a significant amount of their time,” McInnes said. “Feeding appears to be related to the size of the prey whales tackle during extended hunts involving gray whale calves and California sea lions.”
Mr McInnes also said the research team would “really appreciate” any photos or sightings of killer whales. Orca images can be sent to oceaniceologyrg@gmail.com.
