This map shows that many fish stocks have shifted to the north and northeast off northern states in recent years.

Atlantic sea-surface temperatures off the U.S. Northeast coast during the second half of 2012 were the highest recorded in 150 years, according to a report released on April 25 by NOAA’s Northeast Fisheries Science Center.

A deviation in average temperature by more than a degree is uncommon; this increase, from the average of 54.3 degrees F. over past 30 years to 57.2 degrees F. in the second half of last year is the highest jump measured. It is also an amount of warming not seen in any other ocean.

Warming ocean temperatures off the Northeast have meant changing distributions of some fish populations; black sea bass and summer flounder are among the species shifting northeastward.

One NOAA scientist said while it’s not yet clear what these findings will mean for the Northeast Shelf ecosystem and its marine life, that ecosystem is changing.