Not East Coast but you should definitely take a look at Texas A&M Galveston. About 2500 students and the entire school is dedicated to Marine Studies and has tremendous resources as it is considered an Auxiliary of the College Station campus (you even can get football tickets and an Aggie Ring). Large Marine Biology and Marine and Coastal Environmental Science Departments with a broad variety of majors and specialties (for instance you can have a Diving Minor) and is a research monster. The Sea Turtle Research center there is pretty awesome. Outstanding faculty as well.