Otters' Tool Use May Keep Them Fed - And Protect Their Teeth - When Their Preferred Foods Are Scarce

People are often enamored with otters because they’re an adorable animal. They’re also really smart, though. Research indicates they’ve been using tools for thousands of years, even perfecting the technique over the generations. Now new research shows the otters most skilled at tool use may also have an advantage when preferred prey isn’t available.

A study recently published in the journal Science tracked 196 tagged southern sea otters off the coast of California to see how their tool use impacted their dietary patterns and the health of their teeth. While they may be able to bite straight into some of their preferred prey, like sea urchins, other food options have shells that may be difficult to break. If they try to do so with their teeth, it can be damaging. The findings from the research show that using tools like rocks and shells can not only protect teeth but also ensure the animals get their necessary energy consumption when easier options aren’t as available.

Tool use was found to be most common in females, who showed less tooth damage than males. Females were also seemingly more adept at their usage than males, because females who utilized tools consumed prey that was about 35% larger than what male tool users were eating.

Chris Law, lead researcher and postdoctoral researcher at University of Texas Austin, says, “Sea otters vary in how often they use tools. The females are likely using tools to overcome their smaller body size and weaker biting ability in order to meet their calorie demands. Raising pups takes a lot of energy, and the females need to be efficient in their foraging. The study shows that tool use is an important behavior for survival.”

In order to survive in areas where they can’t access sufficient sea urchins or other more accessible prey like abalone, otters must turn to prey like crabs, mussels, and clams. That’s where tools come in, and when accessing this bigger prey with that skill, the higher energy consumption pays off. So does the sparing of their teeth, as teeth damage could lead to starvation.

Not having the ability to access preferred foods can also lead to substantially less energy consumption if tool use doesn’t help them get alternatives. As otters’ prey faces overexploitation, this adaptability could be key in their survival.

Sea otters play a big role in maintaining the health of kelp forests, too, which are important in mitigating climate change impacts due to their carbon storage capacity. If you’d like to join us in helping ensure the otter’s survival, and the benefits it provides, click here!