Raccoons solve puzzles for the fun of it, new study finds

They raid compost bins, outsmart latches and sometimes look gleeful doing it. A new UBC study in Animal Behaviour suggests raccoons may not just be opportunistic—they may be genuinely curious.

UBC researchers Hannah Griebling and Dr. Sarah Benson-Amram from Zoology and Forest and Conservation Sciences, found raccoons continued solving puzzles long after retrieving the only food reward available. This behaviour reflects intrinsic motivation rather than hunger and is described as “information foraging,” because no additional food was given for continuing.

Nine ways in—and they kept going

Researchers used a custom multi-access puzzle box with mechanisms such as latches, sliding doors or knobs. The box had nine entry points, grouped as easy, medium and hard. In Each 20-minute trial the puzzle box contained a single marshmallow, yet raccoons often continued opening new mechanisms after eating it, a clear sign of information-seeking.

“We weren’t expecting them to open all three solutions in a single trial,” said Griebling. “They kept problem solving even when there was no marshmallow at the end.”

When risk rises, raccoons play it safe

When solutions were easy, raccoons explored broadly, trying multiple openings and varying their order. As task difficulty increased, they favoured a dependable solution—but still explored multiple solutions even at the hardest level, showing flexible problem-solving.

Griebling said the pattern reflects a classic tradeoff between curiosity and effort or potential risk. Raccoons adjusted strategy based on perceived cost and risk, mirroring decision-making frameworks in other animals and humans.

“It’s a pattern familiar to anyone ordering at a restaurant,” she said. “Do you order your favourite dish or try something new? If the risk is high—an expensive meal you might not like—you choose the safe option. Raccoons explore when the cost is low and quickly decide to play it safe when the stakes are higher.”

Built for urban life

The findings help explain why raccoons thrive in urban centres like Vancouver. Their success could be attributed to the cognitive and physical traits that suit urban life.

Their forepaws, rich with sensory nerves for foraging in streams, are well suited to manipulating latches and handles—often the same kinds used by humans. Solving problems for information, not just food, may give them an advantage in complex environments, helping them access garbage bins or other food sources. Vancouver’s greenspaces, waterways and generally tolerant public provide near-ideal habitat.

“Understanding the cognitive traits that help raccoons thrive can guide management of species that struggle, and inform strategies for other species, like bears, that use problem solving to access human-made resources,” said Griebling.

Although the experiment involved captive animals at a research facility in Colorado, previous research suggests wild raccoons show similar problem-solving abilities, though researchers caution the behaviours may not be identical. 

“Raccoon intelligence has long featured in folklore, yet scientific research on their cognition remains limited. Studies like this provide empirical evidence to support that reputation,” said Griebling.