Female fur seals, or cows, give birth during this breeding season, then mate again just a few days later. The following year they will return to give birth to a single pup after a nearly yearlong pregnancy, and mate once again.

There are eight species of southern fur seals, all smaller than their northern relative. They include the Guadalupe fur seal of Baja California, the brown fur seal of southern Africa and Australia, and the South 

   

A 2008 survey of the main breeding ground on the Pribilof Islands found the lowest level of northern fur seal pup production since 1916. Climate change may be disrupting patterns of prey abundance in the ocean. As temperatures in the ocean rise, the fish on which northern fur seals depend have begun moving further out to sea, where the water is cooler. If fish numbers are reduced or more plentiful further offshore, seals will need to spend more time foraging, thereby expending more time and energy on feeding and less on reproduction and raising young. This reduces the survival rate of pups, leading to a reduction in the overall fur seal population.

Many seal species depend on sea ice for their survival. As global climate change reduces the extent, duration, and thickness of sea ice, these seal species are threatened with extinction.

As global warming worsens, the (un)natural mortality rate of the harp seals worsens, too. Harp seal mothers need large, sturdy ice floes to give birth to their pups since pups do not know how to swim for the first few weeks of their lives.

The 21st century has seen year after year of poor ice, sometimes leading to the drowning of almost all seal pups born in the Gulf of St. Lawrence, one of the main nurseries for harp seals.

In 2016, this ice report was provided by the National Snow and Ice Data Center (INSIDE), a U.S. agency supported by NASA, NSF, NONA, and other government agencies.

The ringed, ribbon, spotted and bearded seals, collectively known as “ice seals,” are Arctic inhabitants. The entire ringed seal lifecycle relies on ice and rapid ice loss in the Arctic causes seal pups to be prematurely separated from their mothers during the milking period. Rapid ice loss and the inability to build dens for protection leads to high pup mortality.

 

Male northern fur seals are much bigger than females being 30 – 40 percent longer and more than 4.5 times heavier than adult females.