Breeding and Pupping
River otters have delayed implantation, meaning that the egg in the female does not immediately fertilize after breeding. Instead, fertilization does not occur until after the summer, allowing the female to store enough calories to allow the young to develop in the womb during the winter. In the Sierras, river otters usually have their young in March and April, according to the California Department of Fish and Wildlife biologists. Males and females do not interact except for the breeding season, which in the Sierras is between mid-March and April. Litters average two to three young, called pups.
Distribution in the Sierras
River otters in the Sierras live most often in the foothills and lower elevations. Look along river banks, lake shores and other water sources for dens. When swimming, otters leave a serpentine wave pattern along the shore. Look along river banks on steep banks for slide tracks, sure signs of otter activity; they enjoy running up the steep banks and then sliding down into the water on their self-made mud slides. Look around the drainages of Alpine, Mono and Inyo counties, and the Sacramento-San Joaquin drainage areas, according to the website California Animal Facts.
Viewing Etiquette
River otters, like all wildlife, require space. When you see river otters in the water or on shore, do not approach. Use binoculars or a spotting scope to get close views. If the river otters approach you, stand still and silent. Let them go about their business; they are not a threat. If taking photos, use natural camouflage such as shrubs, trees and grasses. Never feed wild animals, including river otters. You can be ticketed and fined for feeding river otters in California.
Article Written By Eric Cedric
A former Alaskan of 20 years, Eric Cedric now resides in California. He's published in "Outside" and "Backpacker" and has written a book on life in small-town Alaska, "North by Southeast." Cedric was a professional mountain guide and backcountry expedition leader for 18 years. He worked in Russia, Iceland, Greece, Turkey and Belize. Cedric attended Syracuse University and is a private pilot.