Research

We clarified the diet and habitat use (using GPS) of this species that urban distribution is rapidly expanding. Our results suggest that they depend on forested areas and expand their distribution by using multiple small green spaces in urban areas.

Diet analysis and body mass comparison

In cities where supplemental feedings by citizens are available, squirrels used high‑energy food year‑round and gained body mass. Feeding may be a key factor in their urban lives.

Survival rate estimation

Rural squirrels live on average about 18 months, whereas urban squirrels live about 12 months. Heavy traffic in cities may create a risky environment for squirrels.

Female reproductive conditions

Increased body mass may improve reproductive performance. In urban populations, pregnancy rates are higher, birth timing is earlier, pregnancies at young age (1 year) are common, and some females give birth twice in spring.

Genetic structure

Urban landscapes would prohibit wildlife's movement and dispersal, causing genetic isolation. Within just 30 years, squirrels living in urban and suburban areas in Obihiro city have become genetically isolated; urban populations show lower genetic diversity and larger inter‑population genetic distances.

Anti-pilferage bahavior

To protect vital winter caches, squirrels carry higher‑value food farther and hide it in places where pilferage risk is lower (i.e., effectively “safer” spots). Squirrels are smarter than we imagine.

Memory enhancement behavior?

coming soon...

Why do people feed wild animals? Semi‑structured qualitative interviews revealed the detailed motivations behind wildlife feeding, and a gap between the motivations assumed by experts and people’s actual motivations.