Veterinarian Examines Bear Claw

Biologist Cracks the Case in Why Some Grizzly Bears Mysteriously Have Missing Toes

 “I did a number of things I never thought I was going to do as a scientist.” That’s how a Canadian biologist described his half-decade scientific quest to determine why some grizzly bears had mysteriously missing toes. Clayton Lamb is one of the premier wildlife scientists in the world. In addition to the academic research he publishes, he also does a great job sharing his work on social media.

While helping a crew tranquilize a big grizzly bear for removal from someone’s lawn in the ski resort town of Fernie, British Columbia. That’s when Lamb noticed the grizzly was missing a piece of its paw. “Grizzlies lead rough lives, brawling and biting one another. So the missing toe of one bear wasn’t necessarily a red flag for us,” Lamb told the Washington Post.

Lamb was conducting fieldwork as part of his Ph.D. program at the University of Alberta when he saw another pear with missing digits. He would go on to find two more bears with the same problem.

Clayton Lamb Sets Out To Solve Mystery Of Grizzly Bears Missing Toes

With no idea what was causing the pattern of missing toes and no leads, Lamb set out on a quest to figure out just what was going on. Grizzlies rely heavily on their claws for hunting and scavenging food and defending themselves. “Part of what makes a grizzly bear a grizzly bear is their very long claws,” Lamb said. “It’s just something essential.” Grizzly bears also use their claws to dig dens.

While monitoring live bears as part of ongoing research, X-ray images of bears with missing toes were taken. Genetic defects were ruled out, as the images showed bone fragments.

Lamb had spent time fur trapping for beavers, otters, and raccoons in his younger years. He started to suspect that the hundreds of mousetrap-like devices that fur trappers utilize for harvesting weasel-like animals called martens could be to blame. He placed 4-traps out in the woods and set trail cameras to monitor them. Sure enough, grizzly bears investigated each trap.

Lamb had heard plenty of stories from fur trappers country accidentally setting their traps on brown bears while targeting smaller mammals. So Lamb took one of the marten traps and set it on a preserved paw from a dead grizzly.

His Discovery Helping Change Fur Trapping Policies

His research showed that the traps weren’t strong enough to cut off a bear’s toe immediately. However, he was able to prove the devices were capable of cutting off blood circulation, which causes the tissue to die and the toes to fall off. “It’s fair to assume that there’s quite a bit of suffering over the weeks or months that these toes are actually falling off,” he said. “It’s not an instant thing.”

The missing toes aren’t perceived to be a threat to the overall sustainability of the species. The pain that it causes individual bears is obviously a concern though. Bears with missing toes also act differently too. They’re more likely to have conflicts with people while searching for food sources easier to grasp without their claws.

One of the ideas to mitigate the problem was to push trapping season back until after bears start hibernating. However, that idea received some pushback for various reasons. Traps being deployed in British Columbia are now required to have a metal plate attached to them. The plate makes the trap opening too small for a grizzly paw to slip into. The opening is big enough for martens though.

Since these changes started being implemented, no additional bears have turned up with more missing toes.