Ospreys face breeding crisis due to menhaden fish shortage

Ospreys in the Mid-Atlantic region are facing significant breeding challenges due to a shortage of their primary food source, menhaden (also known as bunker). In New Jersey, scientists report that the 2025 mating season saw a 57% nest failure rate, the worst in 30 years. Early surveys for 2026 suggest the trend may continue, with researchers observing a reduction in egg-laying by females, a direct indicator of food stress.

Experts note that when prey is scarce, females lay fewer eggs, and males often struggle to find enough food to sustain the nest. This forces females to hunt more frequently, leaving eggs vulnerable to predators, or leads to the total abandonment of nests. In some instances, chicks have been found dead from starvation.

On Long Island, observers have noted that schools of bunker are moving north, potentially due to low nutrient levels like nitrogen affecting the algae they consume. This migration of prey follows the fish and the mammals that eat them, complicating the survival of local predatory birds like the osprey.