STELLER SEA LION BIOLOGY
Steller sea lions eat a wide range of fish, but also consume cephalopods, crustaceans, birds and occasionally other pinnipeds. Analysis of sea lion feces has indicated that the major prey species during the 1990s were walleye pollock, Atka mackerel, salmon, Pacific cod, herring, arrowtooth flounder, cephalopods, rockfish and sandlance. Diet appears to vary between regions and has also changed through time. The causes and consequences of these changes are still under debate.
Sea lions often feed in groups and tend to feed at night between 9 PM and 6 AM. Feeding in groups may help to control the movement of large schools of fish and make them easier to exploit. Sea lions may feed close to shore or may travel 100 or more miles (>150 km) out to sea. Stomach samples and feces (scat) samples indicate sea lions prey upon a wide selection of fishes including capelin, sandlance, pollock, herring, cod, salmon, flatfishes, sculpins, squid, octopus and occasionally seal pups. Most fish are swallowed whole. Large prey are torn apart and consumed at the surface. Food requirements of adult sea lions are believed to be between ~7% of their body weight per day, while juveniles require ~14%
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