TOPIC 'Environment' on Jan 20, 2009 (CET)
Humboldt Squid Is Another Casualty Of Climate Change
The changing environment of the Pacific Ocean is causing the Humboldt squid to be a more sluggish swimmer, thereby becoming easier prey for its enemies. Studies have shown that due to the rising levels of carbon dioxide in the environment, ocean levels also rise. Working harder to traverse the ocean’s waters due to the rising levels and increasing lack of oxygen will cause the squid to slow down and tire faster, allowing sperm whales an easier meal.
Humboldt squid can currently be found from Patagonia to Alaska, swimming at 20 kmh. During the day, the squid must hunt at lower ocean levels to feed on lantern fish. However, the oxygen-deprived deeper waters force a return to the surface during the night for the squid to recuperate from the day’s journeys.
A researcher at the University of Lisbon, Rui Rosa, took squid specimens from the water and placed them in tanks aboard a research vessel to determine how the increased levels of carbon dioxide in the water affected the species. Different levels of carbon dioxide were approximated in each tank.
Rosa discovered that the squid must slow their metabolism by 80 percent to survive in waters where there is no, or very little, oxygen. With the carbon dioxide levels increased in the experimental tanks to what is anticipated for the end of the century, the squid became half as active. Their metabolism will drop further when more carbon dioxide is in the water. Carbon dioxide levels found in the atmosphere are currently at 380 ppm (parts per million), as opposed to the pre-industrial era of man where the carbon dioxide levels were at 280 ppm. The oceans absorb much of this atmospheric carbon dioxide and marine life suffers for it.
One scenario foreseen as the end result of this difficulty in coping by the Humboldt squid is that they will have to migrate to other waters to survive. Owing to the fact that the squid is the primary diet of sperm whales, this transition could begin a domino effect that includes the entire marine food chain.
Sherry Irvin
on behalf of the
BascoTec Internet Limited
Technologie Park 13
33100 Paderborn
Germany
