NEW : Watch CNN.com Live CNN : Live at 4 p.m. , 7 p.m. , 9 p.m . ET . Development in United States ' largest estuary has reduced fish , crabs and oysters . Chesapeake Bay project aims to grow millions of . ` ` moms and dads '' Oysters can help crabs and fish flourish by removing poisons from the water .
NEW : Watch CNN.com Live Earth Day coverage at 4 p.m. , 7 p.m. , 9 p.m . ET . Pollution in United States ' largest estuary has reduced fish , crabs and oysters . Chesapeake Bay project aims to grow millions of oyster `` moms and dads '' Oysters can help crabs and fish flourish by filtering poisons from the water .