Excerpts: "What we captured in 2001 was the loss of those mussels and implications for an entire ecosystem," said Brown University ecologist Andrew Altieri, who with biology professor Jon Witman wrote the study published in the March issue of Ecology. "That's instructive for what historic and future losses might be for the Chesapeake." Altieri calculated that the [mussel] reefs were processing the [Narragansett] bay's entire water volume once every 20 days, even though they covered less than 1 percent of the bay floor. Within days, a hypoxic episode triggered by warm weather, low wind and the usual nutrients contributed to...