Northern Elephant Seal History
by Kristi West
Northern elephant seals (Mirounga angustirostris) are a remarkable species. They faced near extinction and have rebounded remarkably. Pressures of harvesting this population forced them through a bottleneck, leaving a mere 20-100 seals. Yet despite the harvesting, the northern elephant seal population continues to increase 6% per year, and now there are approximately 127,000 northern elephant seals living today (Brownell et al,2000). Below you will find a time line of their history.
Early 1800's to 1860 humans harvested northern elephant seals for their blubber to make oil.
One adult male elephant seal contained enough blubber to produce 25 gallons of oil!!!.
Every time a sealer encountered elephant seals, the seals were killed.
Late 1870's elephant seals were considered extinct due to the pressures of harvesting.
1880, 335 seals were discovered on the mainland of Baja Californa at Bahia San Cristobal, which is south of Isla Cedros (LeBoeuf and Laws,1994 Chapter 2).
Within four years, all of the seals were killed.
1883, 80 seals were discovered on Isla de Guadalupe off the coast of Baja California, allof which were killed. This species was once again considered extinct.
May 1892 two men (C.H. Townsend and A.W. Anthony) found 9 seals on Isla de Guadeloupe. They killed 7 of the 9 and took them to the Smithsonian's museum collection (Townsend 1912).
Small numbers of elephant seals continually showed up at Isla de Guadeloupe up until 1911, and museum collectors continued to kill them for their collections. 1890 believed that there were between 20 and 100 elephant seals remaining.
1890's-1920's northern elephant seals only bred on Isla de Guadalupe. Although they were still being harvested by poachers and museum collectors, the coloney continued to grow.
1922 the Mexican Government made Isla de Guadalupe a biological reserve, protecting the seals from further harrasment and poaching.
After protection from Mexican Government, the seals started to expand to new areas.
Early 1900's elephant seals obsereved migrating from San Diego to southeastern Alaska.
1918 seals first seen on Isla San Benito off the coast of Baja California breeding began here in the 1930's.
1925 seals seen on San Miguel Island off the coast of Southern California breeding started here in the early 1950's.
1948 seals seen on Los Coronados off the coast of Baja California and on Santa Barbara Island off the coast of Southern California. Breeding began on Santa Barbara Island in the early 1950's.
1949 seals seen on San Nicolas Island off the coast of Southern California. Breeding began here in the early 1950's.
1955 seals seen on Ano Nuevo Island north of Santa Cruz California. Breeding began at this location in 1961.
1957 numbers estimated to be 13,000.
1960 numbers estimated to be 15,000.91% of the 15,000 were located on Isla de Guadalupe.
8% of the 15,000 were located on Islas San Benito.
1% of the 15,000 were located on the Channel Islands (San Miguel, Santa Barbara, and San Nicolas).
Although these magnificant creatures have made an amazing come back the population bottleneck that they went through in the late 1800's and early 1900's, is still an important issue. Since all of the current 127,000 northern elephant seals are decendents of the same 20-100, they are all genetically similar (they are all brothers and sisters). This lack of genetic variation makes them very vulerable to new diseases. Very little is known about elephant seal genetics and how they will respond to a new disesase. Scientists are currently doing projects to understand how a new disease would affect this species.All statistics contained in this section were provided by (LeBoeuf and Laws, 1994 Chapter 2)
PelicanNetwork pages about the Elephant Seal phenomena
Elephant Seal Field Guide by Jane Strong
Elephant Seal Gallery by Jackie Van Riessen