Recently, scientists have increasingly been discussing orcas, which are bringing back into fashion "hats" made from dead salmon and terrorizing yachts throughout the Strait of Gibraltar. However, it’s important to remember that these whales are not only intelligent and social but also the largest and most aggressive predators of the ocean, according to Science Alert.
We now have another reminder that orcas (Orcinus orca) are ruthless hunters: researchers have observed a pod of orcas in the Gulf of California developing cooperative hunting techniques to catch the largest fish in the ocean: the magnificent filter-feeding whale shark (Rhincodon typus).
The researchers noted that the pod, which included a male named Montezuma, hunted the marine giants in a manner similar to how another, unrelated group of orcas on the other side of the world hunts sharks off the coast of South Africa. It’s worth mentioning that scientists previously observed that sharks had disappeared from this region, due to orcas hunting their livers.
According to marine biologist Eric Higuera Rivas, it is not surprising that orcas also hunt whale sharks. At the same time, scientists are curious to observe how these whales adapt by mastering various types of strategies for hunting prey. In the case of hunting whale sharks, this pod employs teamwork and specific hunting techniques to immobilize the sharks and extract their internal organs, particularly the liver.
It should be noted that all orcas in the world are classified as the same species, yet they are divided into different groups based on geographical regions: these whales differ both physically and behaviorally. Earlier, researchers also found that orcas from different groups do not mix, but now scientists believe that new speciation is occurring in the ocean.
0Distinct groups of orcas, also known as ecotypes, have their own unique hunting and feeding strategies. Some groups primarily feed on fish, such as salmon, while others hunt mammals like seals and large whales.
The orcas in the Gulf of California have not been assigned a separate ecotype; however, scientists consider them somewhat of generalists: the whales hunt a wide range of prey, including sea turtles and fish. Notably, one intriguing pod has been observed hunting elasmobranchs, a group of cartilaginous fish that includes sharks and rays—scientists have been observing this behavior since the 1990s.
1Researchers have been studying orca hunting behaviors for years and began to notice that among those hunting elasmobranchs, the same individuals were involved, indicating a specialized hunting strategy. In a new study, a team led by marine biologist Francesca Pankaldi from the Interdisciplinary Center for Marine Sciences in Mexico observed four hunts of whale sharks.
The results indicate that in 3 out of 4 cases, a male named Montezuma was involved, and females from his pod were also repeatedly observed—this suggests a single family group that hunts whale sharks.
Footage shows that the attack on the shark was well-planned: first, they ram the whale shark with their heads until they stun and immobilize it. Then, they flip the whale shark upside down and begin tearing at it with their teeth, causing the whale shark to bleed profusely. The main blows are aimed at the belly of the whale shark, specifically where the liver is located.
2Scientists note that they have not observed orcas eating the liver of the shark, but they suspect this occurs. The reason is that the liver stores all the fat of the shark, making it seem like a delicacy for the orcas.
It is assumed that orcas may also consume the stomach and intestines, but scientists cannot confirm this with 100% certainty. However, the bodies of sharks are primarily composed of cartilage and muscle, making them less nutritious for orcas.
Researchers do not believe that such behavior is new, prompted by low prey availability, nor does it pose a threat to whale shark populations. Whale sharks have been visiting the Gulf of California for several decades. Unfortunately, members of this species are extremely slow and defenseless, making them easy targets. Scientists suspect that whale sharks may be on the brink of extinction.