American Red Squirrel vs. Eurasian Red Squirrel

Attribute	American Red Squirrel	Eurasian Red Squirrel
Scientific Name	Tamiasciurus hudsonicus	Sciurus vulgaris
Native Range	North America	Eurasia
Size	Small, about 12-15 inches long	Similar size to American Red Squirrel
Coloration	Reddish-brown with white underbelly	Reddish-brown with white underbelly
Habitat	Coniferous forests	Deciduous and mixed forests

Physical Appearance

American Red Squirrels are small rodents with a body length of about 7 to 8 inches and a tail length of 3 to 6 inches. They have a reddish-brown fur coat with a white underbelly and a bushy tail. Eurasian Red Squirrels, on the other hand, are slightly larger with a body length of 8 to 10 inches and a tail length of 6 to 8 inches. They also have a reddish-brown fur coat but tend to have a more pronounced ear tuft compared to their American counterparts.

Habitat

American Red Squirrels are primarily found in North America, ranging from Alaska to the Appalachian Mountains. They prefer coniferous forests and are commonly found in pine, spruce, and fir trees. Eurasian Red Squirrels, on the other hand, are native to Europe and parts of Asia. They inhabit a variety of forests, including deciduous, coniferous, and mixed forests. Eurasian Red Squirrels have also been introduced to the United Kingdom, where they have thrived in woodlands.

Behavior

American Red Squirrels are known for their territorial behavior and will aggressively defend their territory from other squirrels. They are also known for their vocalizations, including chattering and scolding calls. Eurasian Red Squirrels, on the other hand, are more solitary and less territorial. They are known to be more adaptable and can coexist with other squirrels in the same area. Eurasian Red Squirrels are also known for their agility and are excellent climbers.

Diet

American Red Squirrels have a varied diet that includes seeds, nuts, fruits, fungi, and insects. They are known to cache food for the winter months and have been observed stealing food from bird feeders. Eurasian Red Squirrels have a similar diet, feeding on seeds, nuts, fruits, and insects. They are also known to cache food for the winter and have been known to raid bird feeders as well. Both species play an important role in seed dispersal and forest regeneration.

Reproduction

American Red Squirrels typically breed once or twice a year, with females giving birth to a litter of 2 to 5 young. The gestation period is around 36 days, and the young are weaned at around 70 days. Eurasian Red Squirrels have a similar breeding pattern, with females giving birth to a litter of 2 to 4 young. The gestation period is slightly longer at around 38 days, and the young are weaned at around 70 days as well. Both species reach sexual maturity at around one year of age.

Conservation Status

American Red Squirrels are considered a species of least concern by the International Union for Conservation of Nature (IUCN). However, they face threats from habitat loss, forest fragmentation, and competition with invasive species. Eurasian Red Squirrels, on the other hand, are listed as near threatened due to habitat loss and competition with the introduced North American Grey Squirrel. Conservation efforts are underway to protect both species and their habitats.