Poor pigeons. The threat of man, who has come to think of shooting them in some cities, is not enough. Now the enemy is also hiding in the water. Julien Cucherousset, a French researcher at the University of Toulouse, dubbed the catfish of the Tarn River "freshwater killer whales", which on its banks began to prey on pigeons, developing an effective hunting technique similar to that used by dolphins and killer whales.
He is about to end up run over, his mother saves him
Pigeons. The threat of man, who has come to think of shooting them in some cities, is not enough. Now the enemy also hides in the water. Julien Cucherousset, French researcher at the University of Toulouse, nicknamed “freshwater killer whales"I Catfish of the River Tarn, which on its banks have begun to prey on pigeons, developing an effective hunting technique similar to that used by dolphins and killer whales.
In fact, by swimming for a short time, the fish are able to catching birds approaching the water, then drag them under and drown them. In a study published in PlosOne, scientists investigated this unusual predator-prey relationship between the invasive species, originating from Eastern Europe and the River Rhine and introduced into the River Tarn in 1983, and European pigeons from southwestern France. . The researchers observed the fish from June to October 2011, lurking on a bridge near a gravel islet on the river.
During that time, they recorded 54 pigeon hunting attempts. In 28% of these cases, iThe catfish has successfully captured its prey by dragging it into the water to eat it. These attacks have almost always been triggered by active pigeons, while immobile pigeons have never been attacked. This evidence suggests that the catfish used the water vibrations to hunt rather than visual cues.
In addition to finding that not all catfish feed on pigeons, biologists have also identified a common feature in individuals who do, which are small in size. This could mean that one has been established competition within the catfish population caused by the shortage of prey.
But for now, the cause of this unusual behavior is still unknown. The fact remains that these new findings could bring us closer to understanding the behavioral implications of a species introduced into a new ecosystem.
Roberta Ragni
