Fox froze. Inch from its paws, the rabid carp spawns and writhes in the shallows along the shore of the reservoir. In a sudden flash of movement, the fox dipped its nose first into the water, and appeared with a large carp writhing in its mouth.
In March 2016, two researchers in Spain spotted a male red fox (foxes) hunt and hunt 10 carps over the course of two hours. The event, described in a study published on August 18 in EcologyIt appears to be the first recorded case of fox hunting, the researchers say. This finding makes red foxes only the second type of dog – the group that includes wolves and dogs – known to hunt fish.
“Seeing carp hunting foxes one by one was incredible,” says ecologist Jorge Tobagas from the University of Cordoba. “We’ve studied this species for years, but we never expected anything like this.”
Tobajas and his colleague Francisco Diaz Ruiz from the University of Malaga found a hunting fox while surveying a site for a different project. The fox caught their attention first because it didn’t run away right away when the researchers discovered it. Seizing this opportunity, Tobajas and Diaz Ruiz decide to hide nearby and see what the fox will do.
Their curiosity turned to excitement after the fox caught its first fish. “The most surprising thing was to see the fox catching so many carps without making any mistakes,” says Tobagas. “This made us realize it’s definitely not the first time he’s done this.”
Rather than devouring all the fish at once, the fox hid most of its catch and seemed to share at least one fish with a female fox, possibly its mate.
Fish remains have been spotted in fox remains before. But scientists weren’t sure if the foxes caught the fish themselves, or if they were simply digging up the dead fish. This research confirms that some foxes hunt for their food, says Thomas Gabel, a wildlife ecologist at the University of Minnesota in Minneapolis, who was not involved in the research.
“I would be shocked if this was the only fox that learned how to hunt,” Gable says.
Wolves that live on the Pacific coast of North America and in Minnesota are the only other dog species known to hunt fish (SN: 2/11/20). Gabel says that the fact that two dog species live on separate continents, both fish, opens the possibility that the behavior may be more common than previously thought.
For Tobagas, the hunting fox is an example of how much scientists don’t yet know about the natural world, even for species that live close to humans. “The red fox is a very common species and in many cases it’s a bit disliked,” he says. Foxes sometimes attack domestic animals or livestock and are considered a pest in many places. But “observations like this show us that it’s a wonderful, very intelligent animal.”