Effects of Climate Change

The northern hemisphere  is undergoing tremendous change and the arctic areas, which the Hooded seal inhabits, are expected to undergo the most rapid change. Changes in temperature, ocean circulation, pH balance, ice cover, and sea level are expected due to the warming climate. An additional warming of several degrees Celsius is predicted in much of the Arctic marine environment by 2050 (Walsh, 2008). The sea ice that the Hooded seals use for breeding is expected to deteriorate, causing it to become thinner, less stable and more susceptible to storms and wave action which is bad for the Hooded seal that prefer large heavy ice floes. The actual condition of the ice varies among years making it difficult to predict how seals will respond to future changes (Stenson and Hammill, 2014) and causing great variability in pup mortality (Kovacs et al., 2011).

The Hooded seals extremely short lactation period may help them to withstand the changes of global warming as Stenson and Hammill (2014) predict that it may allow the mothers to ween their pups even in years when ice breaks up earlier than usual. In 2010 however, there was a complete lack of ice in the southern Gulf which probably resulted in either a high mortality of Hooded seal pups or, whelping females moving to the Front. If warming continues, more years like 2010 will be seen more regularly, with lack of ice and poor ice conditions where it is present. This may cause the Hooded seals to move their whelping areas further north and it is likely that the southern Gulf of St Lawrence will be the first area to go (Stenson and Hammill, 2014).

In the early 1920’s there was a significant decline in a short period of time in the number of Hooded seals breeding off the coast of Newfoundland. It has been suggested that climate change, and the subsequent reduction in breeding habitats, may have caused the Hooded seals of that area to relocate eastward and a general decrease in ice condition could mean that Hooded seal breeding areas are moving closer to the Greenland coast (Oigard et al., 2014). The thinner, smaller ice sheets and the movement of the breeding areas towards Greenland may have made Hooded seal pups more vulnerable to predation from predators such as polar bears, and because there is more open water between the ice floes, they may be more vulnerable to killer whales (Kovacs et al., 2011).

As well as affecting the pups, and in turn possibly the population size of the Hooded seals, the decline in ice may also have lasting affects on the adults of the populations. This is because as well as breeding on ice floes, the Hooded seals also only normally haul out on ice (Kovacs et al., 2011). The decreasing ice may mean we will start to see more Hooded seals hauling out on land which may even alter their distribution.

 

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