Tag Archives: Orcas

Orcas and Dolphins Form ‘Friendship’ to Hunt Salmon Cooperatively

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Dolphin approaches killer whale, captured by the killer whale’s camera

University of British Columbia (A.Trites), Dalhousie University (S. Fortune), Hakai Institute (K. Holmes), Leibniz Zoo and Wildlife Institute (X. Cheng)

Killer whales and dolphins collaborate to catch salmon in the North Pacific Ocean, revealing new insights into the intricate social dynamics of marine mammals.

Using video cameras and sensors attached to nine killer whales, researchers observed four of them diving alongside a large group of white-tailed dolphins towards Chinook salmon hiding in deep waters off northern Vancouver Island. An additional three whales were tracked via drone. The killer whales consumed the salmon, leaving behind scraps that the dolphins scavenged.

“They collaborated to locate food,” states Sarah Fortune from Dalhousie University, Canada. “One might anthropomorphize this scenario and suggest that they’re hunting friends.”

Chinook salmon, or king salmon, can exceed a meter in length, making them often too large for dolphins to consume.

However, the whales off northern Vancouver Island are known for their hearty appetites, frequently tearing fish apart to share with their pod, which leaves behind blood, scales, and remnants for dolphins to eat. Researchers propose that dolphins assist whales in locating salmon.

In the video, six out of twelve whales directed their attention toward the dolphins, totaling 102 interactions. The four whales dove with the dolphins to depths of 60 meters, where it becomes dark and salmon can conceal themselves among rocks and crevices.

Though both species emitted clicking and buzzing sounds, data from the sensors indicated that the whales often reduced their echolocation activity, likely to “eavesdrop” on the dolphins. Since echolocation operates like a focused spotlight, having numerous dolphins scanning the waters could enhance the whales’ chances of finding fish, according to Fortune.

“It’s akin to turning on the high beams of a vehicle; the sound serves as the light,” she elaborates.

Prior to this, scientists have noted cooperation among various species, such as fish guiding octopuses to crustaceans and nectar birds leading humans to bee colonies. However, documented interactions between killer whales and other species have often involved predatory behaviors.

Recently, killer whales were reported to have rammed and sunk six sailing vessels around the Iberian Peninsula, suggesting they may be engaging with boats rather than attacking. They are playing with them.

Brittany Visona Kelly from the global conservation group Ocean Wise asserts that the dolphins in this study are not aiding the whales but scavenging leftovers. In a study she and her colleagues, including Lance Barrett-Leonard, revealed drone footage showing whales seemingly ignoring the dolphins, playing with them, and occasionally charging at them. Their findings suggest that dolphins primarily seek refuge from a specific group of mammal-eating killer whales, known as big killer whales, which tend to avoid resident orcas.

“We found no clear evidence that these interactions benefit killer whales,” Visona-Kelly concluded.

The study reported last month indicated that between 30 to 40 white-tailed dolphins encircled an emaciated killer whale known to researchers as “I76,” who remained submerged and did not reemerge. This suggests that the dolphins may have “exhausted I76, making it impossible for him to surface.”

Luke Rendell from the University of St. Andrews in the UK emphasized that the new research provides compelling evidence of cooperation, whether the whales are interpreting dolphin echolocation or drawn to the commotion as a potential indicator of fish.

“These animals are intelligent and possess adaptable behaviors,” he notes. “We witness a range of interactions between killer whales and dolphins, from the former preying on each other to playful interactions and collaborative efforts.”

Topics:

  • whale and dolphin/
  • animal behavior

Source: www.newscientist.com

Video Captures Orcas Preying on Great White Sharks and Consuming Their Livers

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Certain killer whales have a preference for liver, particularly that of great white sharks.

A video captured by Mexican scientists demonstrates how an astute whale targets the apex predator’s fatty organs.

Researchers documented two killer whale hunts in the Gulf of California, one in 2020 and the other in 2022. The footage reveals a group of great white sharks flipping a young shark onto its back, disorienting it, before slicing open its side to extract its liver. The findings from this video study were published on Monday in Frontiers in Marine Science.

In one notable scene, all members of the shark clan feasted on the pink liver fat while the remainder of the shark’s body remained submerged in the ocean depths. A sea lion was seen lurking nearby, seemingly hoping to steal a meal, but orcas released bubbles to ward it off.

Marine biologist and documentarian Eric Higuera Rivas, who filmed the hunt from a nearby boat, initially did not grasp the significance of the footage until he began editing.

“On the monitor, we noticed the shark’s liver hanging out, already dislodged. Moments later, the shark emerged with the liver in its mouth,” recounted Higuera Rivas, a co-author of the study. “I was astonished to learn it was a great white shark. I could hardly believe it.”

Heather Bowlby, a researcher from Fisheries and Oceans Canada not involved in the study, noted that the footage serves as a strong reminder that even apex predators need to stay vigilant.

“We typically view great white sharks as the pinnacle of the food chain,” she stated. “It’s always beneficial to remind them that they can also be prey.”

Higuera Rivas and his team indicated that the hunt appeared to involve members of the same group of killer whales, which they have designated as Moctezuma pods. This pod regularly patrols the Baja California coast, primarily hunting elasmobranchs, including sharks and whales. Higuera Rivas has been monitoring these pods and recording their behaviors for over a decade, noting their adaptations based on the species they target.

Previously, evidence of killer whales preying on great white sharks was limited to South Africa, where they have been known to extract livers and wash the remains ashore.

Alison Towner, a marine biologist at Rhodes University specializing in the South African phenomenon, stated that while behaviors in Mexico and South Africa are similar, they are not identical; Mexican killer whales typically target younger sharks, whereas their South African counterparts focus on adults.

Towner indicated that individual killer whale pods likely learned their hunting strategies independently.

“Observing this behavior in Mexico implies that specific groups of killer whales have developed distinct methods for hunting sharks,” she mentioned via email. “Even though the same organs are the target, the manner in which they are approached varies from what we have documented in South Africa, indicating group-specific learning.”

A new study reveals that Mexican killer whales have discovered a vulnerability in great white sharks.

“When flipped over, a shark enters a state known as tonic immobility,” explained study co-author Francesca Pancaldi, a shark researcher at the National Institute of Marine Sciences. “They become immobilized, akin to a catatonic state. They simply freeze.”

The liver, a nutrient-rich and fatty organ, comprises about a quarter of a shark’s body, delivering “a substantial amount of energy,” he added.

Researchers from both South Africa and Mexico concurred that this hunting behavior is likely not new to killer whales. What has changed for scientists is the advancement of drone technology, which has enhanced the ability to observe and document these hunting events.

“I believe this has been occurring for centuries, but it’s challenging to witness such events,” Pancaldi remarked.

However, she also mentioned that climate changes may have heightened interactions between great white sharks and the octopus pods.

“In fact, we have noticed a growing presence of great white sharks in the Gulf of California over the past decade,” Pancaldi noted, explaining that the species is particularly sensitive to changes in ocean temperatures linked to weather patterns such as El Niño.

According to Towner, scientists in South Africa began observing attacks by killer whales on great white sharks nearly a decade ago. Such predatory behavior has caused great whites to abandon their usual feeding, resting, and breeding spots, referred to as assemblages.

“As a result of repeated predation, great whites have entirely vacated their traditional core gathering sites,” Towner explained. “Many sharks may have relocated offshore or to less monitored regions, which is reshaping coastal ecosystems.”

Following the exodus of the sharks, populations of Cape fur seals and sevengill sharks have surged, leading to conflicts with the primary prey species, such as small fish and smaller sharks, according to the report. This study was published in Frontiers in Marine Science earlier this year.

Mr. Towner noted that only two adult male killer whales, referred to as Port and Starboard, were responsible for the frequent attacks on great white sharks in South Africa. This predation puts pressure on great whites, which have slow growth and reproductive rates, and a similar situation could develop in Mexico if this behavior becomes more prevalent.

Source: www.nbcnews.com

Orcas Cleansing Each Other with Bits of Kelp

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Killer whales demonstrate strong social interactions

Shutterstock/Tory Kallman

Orcas off the coast of North America have been observed engaging in a unique behavior, grooming each other with kelp—showcasing an intriguing instance of marine mammals utilizing tools.

For several years now, scientists have closely monitored a population of 80 endangered killer whales in the Pacific region between British Columbia and Washington. Researchers employed drones to capture a bird’s-eye view of these whales’ activities.

Since analyzing the footage from summer 2024, they have noted Orcas manipulating kelp chains in a peculiar manner. “It’s quite strange,” states Rachel John from the Whale Research Center in Washington, “but whales are known for their quirky behaviors.”

The footage reveals Orcas snapping off kelp stems at the seabed by using their teeth and rocking back and forth on their heads. The segments they break off are approximately the length of their beak-like snout. Remarkably, the Orcas consistently target specific parts of the kelp rather than randomly selecting pieces.

After breaking the kelp, the whales rub it between their heads and the sides of their pod mates, taking turns to groom each other for extended periods—sometimes lasting up to 12 minutes.

“What’s fascinating is that they lack appendages like hands, so they accomplish this using deliberate body movements,” adds John.

Known as “kelping,” this behavior, observed among Orcas, could be a social variation of existing grooming habits. “The social bonds in this group are exceptionally strong, and physical contact is a known way to reinforce these ties,” explains John.

This behavior was observed across all ages and genders within the pod, with the data suggesting that whales of similar ages were more likely to engage in this “kelping” behavior together. Importantly, it may serve as a form of hygiene, says John. The team found that Orcas were more inclined to scrub each other with kelp if they had any skin issues.

While it’s premature to ascertain any health benefits from this behavior, Olaf Meynecke from Griffith University in Australia expresses interest in having researchers compare the skin bacteria of Orcas with kelp properties to identify any correlations.

“It makes perfect sense that they would explore what resources the oceans provide to mitigate skin infections,” comments Meynecke. He believes this behavior may be prevalent among other Orca pods as well as various whale species.

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Source: www.newscientist.com

Orcas Might Be Capable of Tool Use with a Bit of Kelp from a Companion

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The killer whale populations in the southern regions are critically endangered and are protected under the Marine Mammal Protection Act. Currently, their population averages around 73 years. These creatures are highly social, forming close-knit family groups led by their mothers and grandmothers.

Each whale receives a tracking number from the Whale Research Center and is meticulously monitored by researchers, photographers, and whale watchers.

According to Giles, “I would argue that this is the most studied whale population globally, regardless of species, due to the extensive research conducted over the last 50 years.”

What led to this remarkable behavior going unnoticed by researchers for decades?

The issue lay in their perspective.

Weiss remarked, “This behavior is truly inexplicable. It’s predominantly underwater, with approximately two feet of kelp wedged between the two animals.”

Recently, researchers have begun utilizing drones to observe whales from the sky. As drone technology has advanced, so too has the quality of the data gathered.

“A major breakthrough during the 2024 field season was our acquisition of a new drone,” Weiss revealed.

He mentioned that researchers first noticed a whale nudging another whale’s horn in April, followed by about 15 minutes of them rubbing against each other.

Once this unusual behavior was recognized, its occurrence began to increase significantly.

“We started observing it frequently. At least one whale exhibits this behavior every day when we fly the drone,” Weiss said.

Researchers believe this behavior may have been ongoing all along.

Giles noted, “We simply lacked the appropriate perspective. This behavior may have existed since ancient times. We’ve only scratched the surface of understanding these animals.”

For years, Southern resident whales have been at the forefront of conservation efforts. The Marine Mammals Commission reports that these whales face numerous threats, such as decreased prey availability, toxic pollution, and disturbances from ship noise. Studies indicate that without urgent intervention, Southern resident killer whales could face extinction.

Weiss emphasized that these new insights highlight the necessity of protecting the species.

“Through these discoveries, I’ve realized that the later stages of our study present even more to uncover, and we must ensure their survival to learn it,” he stated. “This isn’t just a group of 73 whales; it’s a distinct culture and society. These whales possess a rich array of traditions that trace back thousands of years.”

Source: www.nbcnews.com