Pandion – Osprey

One of only six land-birds with a cosmopolitan distribution habituating all continents except Antarctica

The osprey is a large bird with a wingspan that can exceed 180 cm (71 in). Its body is streamlined for diving with a reversible outer toe to grip slippery fish, dense plumage that repels water, and nostrils that can close during dives. The osprey’s vision is particularly well-adapted for detecting underwater prey from the air. They possess unique angling vision and can adjust for the refraction of light on the water’s surface to accurately pinpoint the location of fish.

Ospreys hunt by flying over water at heights of 10 to 40 meters (33 to 131 feet), then plunging feet-first to capture fish near the surface. Their talons are specially adapted to hold onto their aquatic prey, with spiny scales that help grip the fish securely during flight.

Historically, ospreys were threatened by the widespread use of DDT and other pesticides that contaminated water bodies and fish, their primary food source. The chemicals caused a thinning of their eggshells, leading to a significant decline in successful hatching rates. The ban on DDT in many countries, along with other conservation efforts, has led to a notable recovery of osprey populations. These efforts include establishing protected nesting sites, improving water quality, and mitigating other human impacts on their habitats.

Ospreys are generally monogamous and highly territorial during the breeding season. They often return to the same nesting site year after year, where they perform aerial displays and vocalizations to strengthen pair bonds and deter intruders. They build large stick nests atop trees, cliffs, and human-made structures, such as telephone poles and specially constructed nesting platforms.

The recovery of the osprey from near decimation is considered one of the great conservation success stories. It underscores the importance of environmental regulations and the positive impact of concerted conservation measures. The osprey serves as an indicator species for the health of aquatic ecosystems and highlights the interconnectedness of environmental health and biodiversity.