Corals Moving North
Some Pacific corals have done the equivalent of moving from sunny Atlanta to Detroit, possibly in response to rising ocean temperatures.
A new study of reefs around Japan reveals that a handful of coral species have migrated from the balmy subtropics to temperate climate zones over the last 80 years. The study is the first to track coral reefs for such a long time and over several latitude lines, a Japanese team reports in an upcoming Geophysical Research Letters.
The team, led by geographer Hiroya Yamano of the National Institute for Environmental Studies in Tsukuba, Japan, analyzed maps of corals from four time periods starting in the 1930s. They found that of nine common coral species, four had expanded northward, and two went as far as temperate waters. The study confirms what marine biologists and fishermen have speculated for years. “There were eyewitness accounts of the occurrence, but the data wasn’t so reliable,” says Yamano. “Now we can show very solid evidence.”