A new survey shows underwater grasses in the Chesapeake Bay decreased last year.
Researchers cited high water temperatures and poor water quality as factors in the decline.
The aerial survey conducted by the Virginia Institute of Marine Science found acres covered by the grasses last year dropped seven percent from the year before, but the researchers say the acreage is still at its third-highest level since annual surveys began in 1984.
The results were released Thursday by the Chesapeake Bay Program.
Bay grasses are a key indicator of bay health because they provide food and habitat for many species as well as helping water quality by adding oxygen and trapping sediment.
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