'Striking' footage captures the moment a red fox preys on a wolf pup — a behavior never seen on film before

Striking first-of-its-kind footage has captured the moment a red fox preyed on a 1-month-old gray wolf pup at a nature reserve in Italy.

Scientists monitoring gray wolves (Canis lupus) in the Castelporziano Presidential Estate, a nature reserve about 15.5 miles (25 kilometers) from Rome, had noticed a female with a swollen abdomen. GPS monitors showed her repeatedly visiting a secondary den, suggesting she had already given birth.

Strategically placed cameras revealed two male pups exploring outside the den just days before the attack. Then on May 16, 2025, a red fox (Vulpes vulpes) was filmed entering the den. The first pup escaped, but within seconds the fox exited the den with a pup in its mouth.

At this point the clip cuts out, so the footage does not show the fox or pup leaving the den, but researchers believe the fox likely ate the wolf pup.

The study documenting the observation was published Feb. 13 in the journal Current Zoology.

Mortality rates in wolf pups are high, approximately 40% to 60% of wolf pups die every year. They usually die from starvation, disease, extreme weather and poor body condition. But this video shows predation may also play a small role in their high mortality rates.

The paper is part of a long-term project led by study co-author Marco Apollonio, a researcher at the University of Sassari, to understand more about wolves in Italy.

Tracking wolf pup birth and survival rates is important to help researchers better understand longer-term population dynamics, said study lead author Celeste Buelli, a doctoral student at the University of Sassari, who led the fieldwork and den monitoring. But it isn't easy.

Direct observations of wolf pup deaths are rare as they spend their time in hard-to-monitor dens, she said. The footage is "striking" as it shows an "intense event with a very young animal," she told Live Science.

Study co-author Rudy Brogi, a researcher at the University of Sassari, told Live Science it is likely that the fox ate the pup, as foxes are typically opportunistic feeders — meaning they do not rely on one specific type of prey and adapt their diet depending on availability. In later footage, only one pup can be seen.

It could also be that the fox was simply removing competitors from the area. But Brogi thinks this is unlikely given that foxes sometimes benefit from wolves by scavenging on their leftover kills.

David Macdonald, a zoologist at the University of Oxford in the U.K., has spent decades researching foxes and was not involved in the study. He told Live Science that competing species can kill or prey upon one another, but this behavior "generally involves larger canids harassing or even killing smaller ones."

Whether this behavior is common is unclear from a single video. Brogi said it is "plausible" that it occurs more often than is reported, but more research from "multiple dens and contexts" is needed.

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