Southern right whale: facing a history of whaling and an onslaught of modern threats

The Southern right whale is enlisted as an endangered species.  This is largely due to the commercial whaling industry.  By the 1900s, Southern right whales were being driven to the brink of extinction and were thus the first species of whale to be protected in 1935.

Photo courtesy of WWF

Photo courtesy of WWF

These 60-ton whales occur throughout the southern hemisphere from temperate to polar latitudes.  In this range, they migrate between higher-latitude feeding grounds, and low-latitude winter breeding grounds.  In South Africa, Southern right whales are mainly found along the Cape coast, between Muizenberg and Woody Cape, for their winter breeding, calving and nursing grounds.  Other major wintering areas in the Southern hemisphere include Argentina, Australia and sub-Antarctic New Zealand.  It is estimated that there are about 7000 Southern right whales worldwide.

In the 18th, 19th and 20th centuries, commercial whaling depleted Southern right whale populations throughout the Southern Hemisphere, and almost extirpated the population in some areas.  Whalers called these whales ‘right whales’, because they were the best or the ‘right’ whales to kill.  A reason for this is that the whales had large amounts of fat, which made them float after they had been harpooned, and so they were easy to collect.  These whales were also docile enough to approach, and slow swimmers.  Most importantly, Southern whales were full of highly valued oil, which is used for heating, lighting, crayons and cosmetics.

Image courtesy of the Antarctic Guide

Image courtesy of the Antarctic Guide

Southern right whales colliding with vessels, and getting entangled in fishing gear are leading causes of human-induced mortality.  Since 1983, 23 ship strikes of Southern right whales have been recorded.  However, these ship strikes often go undetected or unreported, and it is highly likely that the number of collisions is much higher than what has been documented.  Since 1963, at least 60 entanglements have been recorded in the Southern Hemisphere, the majority of which occurring in Brazil, Australia and South Africa.  Although, despite the current levels of entanglements and ship strikes, populations of these whales are recovering at three of the primary wintering grounds – Argentina, Australia and South Africa.  However, these nations may further develop their coastlines, which would increase the intensity of threats to Southern right whales.

Southern Right Whale view onto PE full format

The degradation of habitat is also a threat to these whales.  For example, In Argentina, sewage treatment facilities, industrial aluminum factories and fish processing plants are all situated along Golfo Nuevo, one of the major breeding grounds for Southern right whales.  In Namibia, three of the historic calving bays have undertaken major habitat alterations, such as coastal development, vessel traffic, marine mining and oil exploration that have increased over the last 20 years.  Climate change is recognized as a major threat to the recovery of whale populations, because it would fundamentally change ocean conditions and cetacean habitat.  This will affect food availability, migration routes and reproductive rates for whales.  Chemical pollution, increased vessel traffic and kelp gull harassment are additional threats to Southern right whales.

Conservation measures for Southern right whales occur under a variety of federal and state laws.  There are policies, regulations, strategies and plans throughout the Southern Hemisphere.  For information and details on these efforts, please see the 2007 Southern Right Whale 5-Year Review.

At an international level, conservation and protection efforts are promoted by the World Conservation Union’s Red List of Threatened Species, the IWC, and by the United Nations Educational, Scientific, and Cultural Organisation.  The IWC has designated right whales as “Protection Stock” and set their commercial catch number at zero.  Various state and national laws also prohibit commercial whaling.  However, illegal catches of Southern right whales still do occur.

Southern-right-whales-Eub-001

Photo courtesy of the Guardian UK

For more information, please see the International Whaling Commission.

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