What did they eat? The Bald Eagles in this study mostly ate fish - over 95% of the prey we identified were different types of fish. Small mammals, reptiles, and birds made up the other 5% of their diet. Does it surprise you that the eagles ate so much fish?

Click here to view a list of the specific animals we identified in the diet of Bald Eagles. Are there any species that you wouldn't have thought an eagle would eat? See if you can learn to identify each of the species on the list by looking in field guides or on sites like www.enature.com.

Were there differences in diet between salinity zones? We did not find any major differences in the diet of Bald Eagles nesting in different salinity zones. One reason could be because the eagles in our study ate a lot of catfish, shad, and herring. Catfish are mostly a freshwater fish but they are tolerant of saltier water and can be found in several salinity zones. Many types of shad and herring are anadromous fish. Based on the size of the fish we saw the eagles deliver to their nests, the shad and herring they caught were adults. These adults were on migration from the open ocean up to the freshwater portions of the rivers where they lay their eggs. To get from the ocean or Bay to the freshwater, the fish pass through several salinity zones. These characteristics of the catfish, shad, and herring suggest that Bald Eagles could catch the fish anywhere along the river.

What next? Another question we asked in this study was whether or not there were differences in the amount of food available to Bald Eagles nesting in different salinity zones. How is this question different from looking at differences in diet? How would you look for differences in food availability?