Nest Monitoring Program
Our Nest Monitoring Program provides vital insight into the health and behavior of Ospreys in the Severn River watershed. By conducting consistent, detailed surveys each breeding season, we’re able to track long-term population trends and better understand how these birds are responding to environmental changes across the Chesapeake Bay region.
How the Program Works
Each year, our team surveys every known Osprey nest in the watershed by boat, mapping them in Google Earth. Nests are found on navigation markers, man-made platforms, trees, and other structures throughout the area.
At each nest, we record key data points, including:
- Nest location and condition
- Return dates of resident birds
- Mated pairs and eggs laid
- Chick counts (June)
- Surviving juveniles (August)
- Migration departures to South America
To safely and accurately assess nest activity, we use a mirror pole to observe eggs and young chicks without disturbing the birds.
Results and Impact
Recent surveys have revealed concerning trends in Osprey reproduction across the Severn River watershed. Despite consistent nest occupancy, the number of chicks successfully fledging each year has declined, suggesting that food scarcity, particularly reduced availability of menhaden and other key prey species, is limiting breeding success.
Our ongoing monitoring allows us to detect these shifts in real time and evaluate the broader environmental factors contributing to them, such as changing fish populations, water quality and weather patterns.
