In a new study led by University of British Columbia Ph.D. student Hannah Griebling, raccoons (Procyon lotor) continued manipulating complex puzzle boxes long after retrieving the only marshmallow reward, suggesting the animals seek information for its own sake — a behavior that may underpin their urban success.
Multiaccess puzzle box with easy (a), medium (b) and hard (c) solutions. Image credit: Griebling et al., doi: 10.1016/j.anbehav.2026.123491.
In the study, Griebling and her colleagues used a custom multiaccess 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,” Griebling said.
“They kept problem solving even when there was no marshmallow at the end.”
When solutions were easy, raccoons explored broadly, trying multiple openings and varying their order.
As task difficulty increased, they favored a dependable solution — but still explored multiple solutions even at the hardest level, showing flexible problem-solving.
“The pattern reflects a classic tradeoff between curiosity and effort or potential risk,” Griebling explained.
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,” Griebling said.
“Do you order your favorite 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.”
The findings help explain why raccoons thrive in urban centers. 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.
“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,” Griebling said.
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 behaviors may not be identical.
“Raccoon intelligence has long featured in folklore, yet scientific research on their cognition remains limited,” said Dr. Sarah Benson-Amram, also from the University of British Columbia.
“Studies like this provide empirical evidence to support that reputation.”
The team’s results were published February 27, 2026 in the journal Animal Behaviour.
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Hannah J. Griebling et al. 2026. Raccoons optimally forage for information: exploration-exploitation trade-offs in innovation. Animal Behaviour 234: 123491; doi: 10.1016/j.anbehav.2026.123491
