October 23, 1805, in the narrows of Columbia River, more than 100 miles (161 kilometers) from the Pacific Ocean.
Highly variable in coloration; two main color types: white, light gray, yellowish gray, or brownish, with dark spots; and black, gray, or brown with light rings. Male larger than female.
Coastal waters, mouths of rivers, beaches, and rocky shores; some northern populations permanently inland in freshwater lakes.
In the West in the southern Arctic from Yukon and northern Alaska south along California coast. In the East from southern Greenland and Hudson Bay coasts south to Carolinas.
Clark originally misidentified harbor seals seen on the Columbia River as sea otters—he later corrected this mistake in his journals.
