Because sea otter’s don’t have insulating fat, their reddish brown fur consists of two layers and is the densest of all mammals with about 100,000 hairs/cm².
The sea otter’s pelage is brown or reddish brown.
Sea otter fur is the densest of all mammals, with about 100,000 hairs per square centimeter. Because sea otters do not have any insulating fat, the fur is responsible for heat maintenance. The fur consists of two layers: a dark undercoat and longer, lighter-colored guard hairs, which trap a layer of air next to the skin to keep it dry.
Sea otters diligently groom and clean their fur to maintain its insulating ability. Female sea otters groom their pups extensively for 3 months as their coat develops.
• Image | ©️ Andrew Smarius, Some Rights Reserved Unsplash
• Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Lockwood, 2006; Nowak, 1999; Paine, 1993)