Individual ospreys - tracked by satellite and ring-reads over decades - provide a unique window into the welfare of long-lived migratory raptors and the cumulative pressures they face.
Long-term monitoring of individual ospreys reveals both their resilience and their vulnerability. A bird that returns to the same nest for 20 years is demonstrating ecological fitness; the same bird killed illegally during migration represents an enormous loss of individual welfare history. The investment required to make that return - a 6,000 km round trip, twice annually - means that any mortality cause adds to a cumulative welfare burden across a long life. Reducing illegal persecution on migration routes and maintaining high-quality nesting lake ecosystems are the most direct welfare contributions for this iconic species.