Hello, This sounds like a great project. Before providing specific answers to your questions, I need a little more information. You mention waterfowl. Are your students studying multiple species of waterfowl, or are they focusing the project on a single species such as Canada Goose (Branta canadensis)? If the students are studying Canada geese populations they might find this webpage helpful:
http://web.extension.uiuc.edu/wildlife/directory_show.cfm?species=canadagoose It provides information about distribution and abundance of Canada geese in Illinois, as well as information about public health and safety issues and measures that can be taken to prevent and control nuisance geese issues. Once I know which species the students are studying I can provide more specific information. Thanks for writing.