Environment Counts | East coast humpback whale population recovers from near extinction – Australia
Author: Rick Higgins – Published At: 2011-10-17 03:08 – (1848 Reads)
Since 1963 the humpback whale population on the east coast of Australia has risen from as low of around one hundred (100) whales to 8,000 in 2006 and the most recent survey indicates the population in 2010 at approximately 11,000. Surveys indicate the east coast humpback population is increasing at around 11% annually.
Whaling in Australia, mainly targeting sperm whales, continued until 1978, by which time the entire whaling industry was no longer viable.
Since 1963 the east coast humpback population has risen from as low a one hundred whales to 8,000 in 2006, and the most recent survey indicates the population in 2010 at approximately 11,000 and growing steadily at around 11% annually.
The above table summarises population increases throughout the long series of humpback surveys conducted since 1984 to the most recent survey in June – July 2010. Abundance estimates of the east Australian humpback whale population
The annual migration of the Australian east coast humpback whales covers some 10,000 km north from the Southern Ocean in June to August and back south in September to November. In the Antarctic waters they feed on krill (an adult humpback consumes up to 1.5 tons of krill daily) before their migration north to sub-tropical waters off Queensland where they mate and give birth. The timing of the migration period can vary from year to year depending on water temperature, sea ice, predation risk, prey abundance and the location of their feeding ground. Groups of young males typically lead the migration while pregnant cows and cow-calf pairs bring up the rear. Adult breeding animals form the bulk of the migration in the middle stages.
Beginning in Australia shortly after European colonisation, whaling and the export of whale products became Australiaâ€™s first primary industry. Australian whalers of the early 19th century hunted from small boats, towing their catch back for processing at shore stations. The development of harpoon guns, explosive harpoons and steam-driven whaling boats later that century made large-scale commercial whaling so efficient that many whale species were over-exploited in the 20th century and came very close to extinction.
When southern right whales and blue whales became scarce, Australian whalers began to target humpback whales, killing approximately 8,300 off the east coast between 1949 and 1962. Whalers from the Soviet Union continued to whale illegally throughout much of the Southern Ocean, killing 48,700 humpbacks between 1947 and 1973. More than half of these were taken in the two whaling seasons of 1959â€“60 and 1960â€“61. The net result of all the Southern Ocean and Australian east coast whaling of humpbacks was the total collapse of the humpback population to near extinction.
The Australian Government notes “the recovery of the humpback population has contributed significantly to the rapid growth of Australiaâ€™s whale watching industry. The Australian National Guidelines for Whale and Dolphin Watching 2005 have been developed to minimise impacts on whales, dolphins and porpoises and to give people the best opportunity to enjoy and learn about them.” Australian Government Humpback Whale Factsheet
Source: Abundance estimates of the east Australian humpback whale population: 2010 survey and update Michael J. Noad et al.
The International Whaling Commission (IWC) provides extensive information and access to whale population surveys.The International Whaling Commission