Big changes in the Sargasso Sea
A survey of the Sargasso Sea has found a disturbing loss in biodiversity.
Field research in 2011 and 2012 led by the Monterey Bay Aquarium Research Institute (MBARI) found that the region of the North Atlantic known as the Sargasso Sea appeared to have suffered a loss in biodiversity since in the early 1970s, which was the last time a detailed study was made of the area.
For example 13 species of animals in different groups - including crustaceans, worms and sea spiders - that had been observed in the past, were missing in recent samples.
The researchers did not have enough data to determine whether the changes were the result of long-term shifts in ocean conditions or due to natural variation.
A series of follow-up expeditions are planned.