Scientists who study the wolves in northern Minnesota are sharing an "incredible and rare" observation they made this week.
Warning: This story contains graphic images.
Members of the Voyageurs Wolf Project study the behavior of wolves in the Voyageurs National Park in northern Minnesota.
Earlier this week, Project Lead Tom Gable made a "fascinating observation" involving a wolf born in 2019, with a post on the project's Facebook page saying, "This is the first time we have ever seen anything quite like this in our area."
Gable discovered a wolf from the Wiyapka Lake Pack had scavenged the carcass of a wolf pup, born this year, and then buried the pup's head for later, he explained in a Facebook video posted Thursday.
While wolves are known to scavenge and cache things for later, what makes this observation "particularly intriguing" is the wolf who buried the pup skull shares the same mother as the dead pup – so the wolf scavenged the remains of his sibling, the project explained on Facebook Friday.
"We have not seen another instance like this before," the project said.
Gable said he discovered the pup skull buried under a tree after noticing a large disturbed area in the snow with cracked bones and nearby wolf tracks, where the wolf ate the pup carcass.
He followed the wolf tracks about 40 meters, where he saw another disturbed area and digging under a tree – he used a stick and found the skull, which the wolf presumably buried so he could come back and snack on it later.
Based on the condition of the skull, project members believe the pup, who was about 5-6 months old, died 1-2 weeks before its sibling fed on its carcass. They don't know why the pup died, but they believe it was likely due to starvation, which is the most common source of mortality for pups at this time of year.
The wolf likely ate his sibling's carcass because "food is food, and wolves scavenge all sorts of dead and rotting animals," the project said, including other wolves. "When wolves find dead animals, they often eat them because it is free food. It appears that wolf pups can fit that bill as well."
The project provided further explanation in a comment on Facebook;
"We have definitely documented wolves eating/scavenging carcasses of other dead wolves. What we have not seen is an adult wolf scavenging the remains of a pup from its own pack. We honestly have no idea what the motivation is for this or what triggers this kind of behavior. That said, wolves commonly eat dead and rotting carcasses they find in the woods and perhaps they view a wolf pup like this no differently when times are lean. Hard to know for sure though."
The Voyageurs Wolf Project also shared photos of the discovery on Facebook, saying "We know these photos might be off-putting for some but we think the observation is too interesting not to share, and ultimately, this is the way the natural world works."
As for the pup skull, project members collected it for their records and samples because they rarely get the opportunity to collect this type of data.
Removing the skull won't impact the wolf's survival, the project notes, but they did carve off the flesh from the skull so the remaining meat is there for him if he wants to eat it.
Bring Me The News has reached out to the Voyageurs Wolf Project for more information.