Skip Navigation

Northern River Otter

northern_ river_otter_512x219 Although a rare sight, river otters may be seen in small family groups (also known as romps) sliding, wrestling, and somersaulting along the Illinois River at Arapaho Refuge. 

The endearing playful behavior of river otters is not only entertaining to a bystander, but this “play” is inadvertently significant and is important practice of survival skills that young otters will need throughout their lifetime. Otters inhabit riparian habitats and are dependent on high quality, permanent bodies of water, but are equally at home in the water and on land. Their favorite food is fish, but they also eat crayfish, frogs, small mammals, and aquatic insects. Otters are amazingly adapted to the aquatic environment with a hydrodynamic body-shape, short webbed feet, and incredibly dense hair containing nearly 160,000 hairs per square inch; essentially creating a waterproof barrier that keeps them warm in frigid waters. They can swim up to 12 mph and run 18 mph on land. They are known to swim beneath ice and use trapped air bubbles to breath, but when air bubbles aren’t present, they can hold their breath for up to 8 minutes! The number of otters inhabiting the Refuge is unknown. They are listed as a “threatened” species in Colorado. Most observations of otters on the Refuge occur along the bridge crossing the Illinois River on the entrance road and along the Moose-Goose Nature Trail.  

Learn more about river otters from Colorado Parks and Wildlife  

Kids:  learn more about river otters 

Last Updated: Apr 12, 2013
Return to main navigation