Newly released surveillance footage captured the moment a vicious animal decapitated a baby seal in California. 

For approximately ten years, headless bodies of deceased seal pups have been discovered on California beaches, puzzling experts as to the cause of these disturbing killings. However, recent findings have shed light on this mystery.

In 2015, the alarming trend began when numerous dead baby seals were found along the coast, as reported by Sarah Grimes, the stranding coordinator at the Noyo Center for Marine Science in Mendocino County, according to an article by SF Gate.

The distressing video, captured in the early hours of April 30, 2024, showed the culprit in action – a coyote. 

The carnivore was seen placing its paw on the body of a seal as it bit the animal’s head and ferociously tugged at it. 

Subsequent investigation and footage were made possible through the collaboration between Grimes and Frankie Gerraty, a UC Santa Cruz Ph.D. student studying the interaction between marine and terrestrial species.

‘What she told me was compelling enough that I was like, “OK, we need to get cameras out there and see what’s going on”,’ Gerraty told the outlet. 

He said a Browning Strike Force HD Pro X camera was set up on a piece of driftwood in the sand. The device is designed to capture movement during the night. 

Although he anticipated capturing footage in time, Gerraty was surprised to see movement just two days after mounting it. 

He was stunned to learn that the mystery attacker had finally been found, but was also equally as shocked that it was the first time coyotes had ever been caught hunting harbor seals in the state. 

Gerraty quickly informed Grimes of the news, and the pair, along with others, have gone on to study exactly why and how this is happening. 

‘One of the most exciting things about studying these animals, especially coyotes, is that they continue to surprise us,’ he said. 

‘They live in our backyards, and we interact with them pretty regularly. Yet we’re realizing that they do so much more than we had ever anticipated.’ 

Grime and Gerraty and other co-authors – Sue Pemberton, Sarah G. Allen and Sarah A. Codde – published a study on February 12, 2025 to the Ecological Society of America on their findings from 2016-2024. 

Their research found that there were 59 instances of baby seals being attacked by coyotes, a majority of which were recorded at Bolinas Lagoon, Drakes Estero in Marin County, and at MacKerricher State Park – also known as the site of ‘serial pinniped predation.’ 

In Drakes Estero, footage caught two coyotes tag teaming a group of seals that were resting along the edge of a sandbar. 

‘They were being sort of sneaky, trying to approach larger groups of harbor seals and then pretty much grabbing the slowest or most accessible ones and killing them with bites to the back of the head and neck,’ Gerraty recalled, adding that the mammals were also going for the marine animal’s flippers. 

After pouncing on the seals, the coyotes would then drag their bodies back higher up on the beach to eat in peace and save for later. 

A majority of the coyote’s victims were just less than two weeks old, weighing approximately 29-33 pounds – about the same weight as the predators. 

Gerraty said that although it might seem odd that the coyotes chose to go for the seals’ heads, carnivores have used that tactic before. 

For the harbor seals on the shore of Northern California, Gerraty said that ‘it’s likely’ that coyotes go for the heads first ‘because it’s not only the easiest part of the body to access with the thinner layer of blubber, but the brain also has the highest nutritional value.’ 

He further explained that the skull of a seal pup is slightly thicker than an eggshell, making it easier for a coyote to crack it open during its attack. 

The power of the animal’s bite also exposes more of the pup’s flesh when it tugs on its head. 

‘The fact that some of the skulls are going missing could be because they can easily carry them back to their dens for their young to consume. 

‘Much of this is happening during peak pupping season for coyotes in the spring,’ Gerraty added. 

Camera footage also revealed that coyotes weren’t the only animals feasting on the young pups, as turkey cultures, ravens, gulls, rodents, and even bald eagles, which are endangered in California, got their hands on them. 

‘I think it goes to show that coyotes are often vilified in the media for doing the things that coyotes do, which includes hunting,’ he said. 

‘But sometimes we don’t appreciate the ways that coyotes can serve our wildlife habitats.’ 

Coyotes are known for their hunting skills, and along with seals, they have been known to prey on seabirds, fish and intertidal invertebrates, which include sponges, shrimp, sea urchins, and more. 

Gerraty believes the number of incidents will only increase in the coming years. In 2019 alone, he suspects that more than 30 percent of baby seals at MacKerricher State Park were hunted down by the wild canines. 

In reality, he thinks that number is actually higher, adding: ‘I definitely think that coyote predation of harbor seal pups is more common. It’s just gone largely undocumented.’ 

He also thinks that the seal population could turn to other areas to rest and give birth in an effort to avoid the predators. 

‘It could also be a sign that they’re going to become more vigilant, and maybe they’ll get better at avoiding predation,’ he noted. 

Gerraty didn’t release the footage back then because they were in the process of conducting more research for the study. 

One of the first sightings of headless seal pups was made in 2016 by Steveston resident David Stuart, who was walking his dog on the beach.

Stuart noticed the body was without cuts, and the one around the neck was ‘surgical,’ he said.

‘The seal’s rectum has been removed and cauterized; it makes no sense,’ Stuart told the Richmond News in 2016.

‘This was a crime scene as far as I was concerned; this needed to be looked at.’

He notified authorities who believed the wounds were ‘consistent with that of a large propeller.’