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Greenpeace Southern Oceans Tour (1999/2000): Greenpeace tries to stop 
a minke whale from being hauled onto a Japanese whaling vessel.

Greenpeace Southern Oceans Tour (1999/2000): Greenpeace tries to stop a minke whale from being hauled onto a Japanese whaling vessel.

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Whales face a number of human threats such as commercial whaling, climate change, pollution, over fishing, ozone depletion, noise, being struck by ships and commercial whaling.

Over fishing threatens whales’ food supply, and whales can become entangled in fishing gear.

Climate change

The devastating impacts of climate change are already being felt across the globe and the oceans are not immune.

In particular, species that inhabit polar regions are likely to be impacted more acutely because the temperature rises predicted for polar regions are significantly higher than global averages.

The Southern Ocean around Antarctica, where a large proportion of the world's great whales feed, is already being affected, as observed by the substantial melting and collapses of the Larsen A and B ice shelves.

Higher temperatures reduce sea ice and impact the entire Antarctic marine food web. Sea ice forms a highly productive environment, with single celled plants known as phytoplankton growing in high densities under the ice.

Phytoplankton feed small crustaceans including krill, which in turn feed most Antarctic species including the great whales. A reduction in sea ice implies a reduction in krill and therefore, food for whales.

Toxic contamination

Ocean pollution is contaminating whales. In some areas, whale blubber has been found to contain high levels of pesticides and organochlorines such as polychlorinated biphenyls (PCBs).

The levels are so high that the blubber would be classified toxic waste.  PCBs are highly toxic chemicals that are linked to damaging children’s development and affecting reproduction.

Despite all of these threats, some nations, particularly Japan, want to resume commercial whaling.

Commercial whaling

An increasing number of nations in the International Whaling Commission (IWC) are voting for an immediate resumption of commercial whaling. This is a NOT a result of a changing world opinion; it is because the Fisheries Agency of Japan is operating what it calls a 'vote consolidation program'. This gives fisheries aid to developing countries in return for their vote at the IWC.

When the IWC agreed the moratorium on whaling in 1982 it had 37 active members, of which seven supported continued whaling. At the meeting during 2005 in Ulsan, Korea, it had 66 active members and 23 of them voted for an immediate resumption of commercial whaling.


At the most recent IWC meeting on the Caribean island of St Kitts, the pro-whaling nations were able to pass the non-binding but dangerously worded St Kitts and Nevis Declaration by a vote of 33 to 32 with one abstention. This document urges the IWC to resume management of commercial whaling. This was the first vote the whaling nations have won since the moratorium on commercial whaling came in to effect. It was a purely symbolic victory for the pro-whalers, but it still has set a dangerous precedent at the IWC. The IWC is now on a knife's edge as to whether it will continue to protect whales or begin exploiting them once again.

Disappearing species

Expectations for the recovery of whale populations have been based on the assumption that, except for commercial whaling, their place in the oceans is as secure as it was a hundred years ago. Sadly, this assumption is no longer valid.

The blue whales of the Antarctic are still at less than 1 per cent of their original abundance despite 40 years of complete protection.

Some populations of whales are recovering but some are not.

Only one population, the east pacific grey whale, is thought to be near its original abundance but the closely related west pacific grey whale population is the most endangered in the world, hovering on the edge of extinction with just over 100 remaining. The number of Antarctic whales is less than 10 per cent of what it was before whaling began.

Recent DNA evidence shows that the impact of commercial whaling may be even worse than previously thought. Most estimates of historic whale population size have been extrapolated from old whaling figures, but this method is often very inaccurate, argues marine biologist Steve Palumbi of Stanford University's Hopkins Marine Station in California, US.

In 2003 Palumbi and his colleagues used DNA samples to estimate that humpback whales could have numbered 1.5 million prior to the onset of commercial whaling in the 1800s. That number dwarfs the figure of 100,000 previously accepted by the IWC based on 19th century whaling records. Humpback whales currently number only 20,000.

IWC figures fail whales

Japanese delegates to the IWC constantly refer to a 1990 estimate of the Antarctic minke population of 760,000. But that figure was withdrawn by the IWC in 2000 because recent surveys found far fewer minkes than previous surveys. The new estimates are approximately half the 1990 estimate in every area that has been resurveyed.

The IWC’s scientists do not understand the reasons for this and so far have not been able to agree a new estimate.