Fish sandwiches may be skimpier in the future as the planet's oceans continue to warm.
Biologists measured progressively smaller average lengths of edible fish in the northern Atlantic Ocean between 1970 and 2008. Six economically-important fish species - haddock, herring, Norway pout and plaice - declined in length by an average of 23 percent.
The fish lived in different environments from bottom-dwelling plaice to surface-skimming herring. The range of habitats suggested that some common factor was altering the entire ocean community in the North Sea, a section of the Atlantic rimmed by Scandinavia, Great Britain and Germany.
ANALYSIS: Climate Change Could Shrink Animals
During those same 38 years, the average seafloor water temperature increased by 0.2–0.6 degrees Celsius per decade, for a total of one to two degrees C, in the North Sea. Besides the increasing water temperature, no other factor, such as commercial fishing, affected the fish universally, noted the authors of the study published in Global Change Biology. The biologists concluded that climate change may be shrinking economically important fish species.