Killer whale, female predation

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The killer whale that roamed the Seine on Monday finally died. Marine mammals are one of the top predators, at the top of the ocean food chain.

His ordeal lasted several days to its tragic end. The killer whale that roamed the Seine He was finally found dead on Monday, when the decision was made to euthanize the very weak animal. But why did these marine mammals end up in a river far from their natural habitat? The first hypothesis put forward after the discovery of the animal in the Seine: the killer whale is sick, he would have been rejected by his family. A theory disputed today by many specialists contacted by RFI. “There is great solidarity among the orcas, Confirms the head of the NGO Sea Shepherd France, Lamia Essemlali. Remember these photos were taken in British Columbia [sur côte ouest du Canada] Orc’s mother had carried the carcass of her calf for several days. »

Sea Shepherd France refers to human activities and in particular noise pollution in this area of ​​Le Havre, at the mouth of the Seine. Killer whales communicate with each other by whistling and locate each other by echoing by broadcasting clicks. Perceptible signals up to 10 km. But after that, it is impossible to find his family. “There is a lot of marine traffic, massive noise pollution, Lamia Al-Asmali confirms. So it is possible that the orca lost their group by accident and that they once had trouble feeding themselves, which explains why they are so emaciated. »

whale killers

Because killer whales hunt in groups with remarkable intelligence. These predators, weighing several tons, at the top of the food chain, for example, can violently bang their tail on a piece of ice to knock a seal into the water. We’ve also seen an orca emerging from the water, its mouth wide open, when the penguin threw itself into the water from the top of an ice pack. Killer whales, found in all oceans, are also able to attack sharks and even whales. This is also the name orca in English: killer whalesWhale killer.

In French, orque is a female name, because with this dolphin’s cousin, it is the female who leads the dance, who knows where the prey is and how to catch it. Maternal organization is undoubtedly due to the longevity of the female, which exceeds 80 years, even if the orca is no longer able to reproduce in the middle of its life. “What is the point of surviving so long when you are no longer contributing to the reproduction of the group? He interrogates Christophe Jeanette, director of research at the National Center for Scientific Research and a specialist in marine mammals. we IHe explained through the effect of this experience. Dominant killer whales will raise their own young, of course, but they will also be involved in raising their grandchildren and daughters. This could explain the role of dominance, due to this experience, within orca families. »

mother power

Thus, females live nearly twice as long as males. “The moment the mother, the founding institution, dies, the daughters tend to separate and leave with their immediate grandchildren, their sons and daughters, Christophe Genet continues. And what we also noticed was that in the two years following the mother’s death, her sons would die because their sisters rejected them. » Nature is cruel sometimes.

At the top of the food chain, killer whales have only one enemy: humans, especially fishermen who shoot them when they get too close to their nets. Or that, through overfishing, are depleting orcas’ food resources. Even major predators are at risk.

Question of the week

Are humans super predators?

Homo sapiens is even an excessive predator. The only animal that kills more than one reason, just for fun, and the largest of prey, the adults, when other predators are feeding on weaker prey. Apart from humans, responsible for the extinction of many species, major predators contribute to the balance of nature. This is the case of the wolf, for example, which was reintroduced in Yellowstone Park in the United States. Its return helped organize the dens that had devoured the vegetation. The birds are back, as are the scavengers and the beavers.. There is no need for the wolf to cry!

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