Dr. Richard O. Bierregaard, Jr. knows! He has been studying ospreys for over 40 years. In 2000, in collaboration with Dr. Mark Martell, he began installing GPS tracking devices on young ospreys to track their migration patterns, including several from the Chesapeake Bay region. Ospreys have been tracked to winter quarters in the Caribbean, Central and South America, as far south as Peru! His tagged birds have names and his website is updated regularly with their progress. By September 12, three birds, Penelope, Sr. Bones and Thatch (Thatch is from Delaware) had begun the long and perilous journey south. Gunny left on September 19 and arrived in Virginia Beach on Tuesday. Other tagged birds, including Neale, Sanford and North Fork Bob, should be leaving soon. To follow their progress, go to: http://www.bioweb.uncc.edu/bierregaard/migration10.htm. I have to admit that following these birds as they make their way south and, hopefully, back north again could become an addiction.
If they survive the journey and winter, they will return around mid-March to nest near the area where they were born. Ospreys begin mating at three years of age and will often mate for life. Nests consist of bulky piles of sticks on navigational markers, duck blinds, utility poles or high up in a pine tree, but always near the water. Females usually lay three eggs in mid-April to late May. By July, the fledglings fly from the nest and begin to practice their steep dives to catch fish.
Ospreys are sometimes confused with bald eagles. It’s certainly easy to do – ospreys look remarkably similar to both juvenile and adult bald eagles. Here’s a brief primer to tell them apart: ospreys are dark brown or black with white underparts, a broad black eye stripe and a black patch on the underside of the wings. Adult bald eagles have white heads and tails but dark underparts, while juvenile bald eagles are all brown or mottled brown and white all over. Ospreys are slightly smaller than bald eagles and fly with their wings "crooked" in an M shape, whereas bald eagles fly with their wings in a flat line.
We are fortunate here in the Chesapeake Bay region to have the largest nesting population of ospreys in the world, over 2000 pairs which accounts for 25% of the US population. While they are wintering in warmer climes, I hope to follow the travels of Penelope, Sr. Bones, Thatch and Gunny and will eagerly await their return in the spring!