Anatomy and Biology

Elongated body

Rich brown color, grey around throat and muzzle and underside

Fully webbed feet

Sharp teeth and strong jaws

Short, dense, waterproof fur

Anteriorly positioned eyes 

Membranes cover eyes when swimming

Ears close when submerged in water

Males are on average 5% larger than females

2.5-5 ft long, 10-30 lbs

River Otters scent mark using paired scent glands (strong, musky odor) or by urinating/defecating on nearby vegetation