Raccoons are criminal masterminds, but which are more mischievous? Researchers now know

What personality and behavior traits make raccoons more highly skilled bandits in urban areas? That's the question a team of researchers in Wyoming set out to investigate.

Researchers trapped and tagged 204 wild raccoons in Laramie, Wyoming, between August 2015 and September 2019, according to a study published in the Journal of Experimental Biology.

As they tagged the raccoons, researchers noted their personality traits: Was the raccoon bolder and aggressive? Or calmer and more shy?

Then researchers set the stage: They placed a number of boxes in the area equipped with a two-button device. If raccoons pushed the correct button, the box dispensed food for them. After a while, the "correct" button and the wrong button were flipped, according to the study.

This experiment tested the ability of different raccoons to learn — and relearn — how the treat box worked. Researchers recorded the number of mistakes different raccoons made.

The more docile raccoons — those that were "shy, less aggressive and less active" — showed greater flexibility in learning from the treat box, researchers said.

Younger raccoons showed a similar tendency, but researchers said the study included too small a group of young raccoons to make strong conclusions.

Researchers warned that attempts to deter raccoons from mischief by killing bolder raccoons may have the opposite effect. This strategy likely leaves calmer raccoons to mate and pass on their higher human avoidance skills alongside their banditry skills.