Northern Elephant Seal (Mirounga angustirostris)
Did You Know?
- Adult males use their large, inflatable noses during the winter breeding season to resonate sound when vocally threatening each other.
- The largest colonies of Northern elephant seals are found off southern California in the Channel Islands.
|males up to 4,400 pounds (2,000 kg);
females up to 1,300 pounds (600 kg);
pups are about 75 pounds (35 kg) at birth
|males up to 13 feet (4 m);
females up to 10 feet (3 m);
pups are about 4 feet (1.2 m) at birth
|pups are black until they are weaned at about 6 weeks old, they molt and turn light silver;
adults are dark brown or gray;
males develop a large inflatable nose, or "proboscis," when they reach puberty (around 7 years old)
|13-19 years, with females living longer than males|
|mostly squid and fishes, but also rays and sharks|
|When they return to land to breed or molt, they fast.|
Northern elephant seals are the largest phocid, or "true" seal, in the Northern Hemisphere. Fully grown males can reach lengths of over 13 feet (4 m) and can weigh nearly 4,400 pounds (2,000 kg). Females are significantly smaller than males, but are also quite large growing to about 10 feet (3 m) long and weighing up to 1,300 pounds (600 kg).
Pups are born in early winter from December to January. Breeding occurs from December to March, and gestation lasts around 11 months. Northern elephant seals are "polygamous"; males establish dominance over large groups of females during the breeding season.
Northern elephant seal pups are about 4 feet (1.2 m) long and weigh about 75 lbs (35 kg) at birth. Pups are generally black until they are weaned, when they are about 6 weeks old. They then molt and turn light silver. They gradually become darker brown or gray, though they often remain pale ventrally, or on their underside.
When males reach puberty at about 7 years old, they develop a large inflatable nose, or "proboscis." The proboscis overhangs their lower lip by about 8 inches (20 cm). They also develop a robust, thick neck that is heavily creased and lighter in color--even slightly pink--compared with their dark bodies. Conversely, females maintain their smaller noses and smooth necks.
There is also a notable difference in life span between males and females. Females generally live for about 19 years, while males only live for about 13 years.
When at sea, Northern elephant seals feed mostly on squid and fishes, but they also eat rays and even sharks. When they return to land to breed or molt, they fast. During these fasting periods, they can lose up to half of their body mass!stock assessment reports with population estimates are available on our website.
- entanglement in marine debris
- fishery interactions
- boat collisions
|Stock Assessment Reports||-||various|
- NOAA National Marine Mammal Laboratory Northern Elephant Seal Information and Research
- NOAA's National Marine Sanctuaries
- Southall, B. L. R. J. Schusterman, and D. Kastak. (2003). Acoustic communication ranges for northern elephant seals [pdf]. Aquatic Mammals 29, 202-213.
Updated: January 16, 2015