In Willapa Bay in Washington state, scientists discovered that water washing over tidal flats during high tides is largely the same water that washed over them during the previous high tide. This ‘old’ water has not been mixed with ‘new’ water and has lower levels of food for creatures in the bay. Oysters grown on flats where ‘old’ water stays longer showed a 25% drop in dry tissue weight per shell height.
Click here for original story, Tides don’t always flush water out to sea
Source: ScienceDaily