Linked from
The 20 pages that link to Sea otter, each with the reason it gives.
PredationBroader topic: Sea otter predation can limit urchins and affect kelp forest structure.
MustelidaeBroader topic: This species is a distinctive example of mustelid adaptation to ocean life.
MolluscivoryBroader topic: Its use of stones as tools helps it open hard-shelled mollusks.
Webbed footBroader topic: Webbing on its hind feet helps it swim and maneuver.
OtterBroader topic: It is the most fully marine otter and uses tools to handle prey.