When Captain John Smith first arrived in the Chesapeake Bay during the early 17th century, he noted such an abundance of oysters that it made it dangerous to navigate his ship. About 100 years later, Francis Louis Michel remarked, "The abundance of oysters is incredible. There are whole banks of them so that the ships must avoid them. They surpass those in England by far in size; indeed they are four times as large." But five centuries later, the oyster populations are but a fraction of those first seen by Captain Smith.
American or Atlantic oyster - is a tolerant organism able to withstand wide variations in temperature, salinity, suspended sediments, and dissolved oxygen. Found in estuaries, sounds and bays, the eastern oyster plays an important role in the health and survival of the Chesapeake Bay. Aside from the obvious economic role it has on Maryland's economy, the American oyster filters algae from the Bay improving water quality for all organisms that depend on the Bay. A paper by UMCES scientist Roger Newell in 1987 made the dramatic point that oyster populations at the beginning of the century could have filtered the entire Chesapeake in several days, while the populations remaining at the end of the 20th century would take more than a year.