Cormorant Departure Restores Bird Diversity on Estonian Sea Islands

The cormorant, selected as Bird of the Year 2024, has significantly reduced other bird populations on Estonian sea islands in recent decades. Research shows that where cormorants depart, the bird world gradually begins to recover.

The cormorant — a large, dark-feathered and fish-eating bird — has become a serious challenge for the nature of Estonia's sea islands. In recent decades, this noisy bird has significantly reduced the diversity of other bird species on sea islands, causing concern among naturalists about the balance of local ecosystems.

Cormorant nesting sites affect the surrounding environment drastically: birds destroy vegetation with their droppings, eliminating shelter and nesting opportunities for many other species. Densely populated colonies make islands essentially uninhabitable for other birds, as plant cover dies and the ground becomes bare.

Recovery After Departure

The encouraging news, however, is that nature's capacity for recovery is surprisingly strong. In regions where cormorant colonies have departed or have been successfully relocated, rapid improvement in bird diversity has been observed. Plant cover begins to regenerate, and with it return other bird species that had previously retreated from the area.

Estonian ornithologists stress that regulating cormorant populations is a complex issue requiring careful consideration. On the one hand, it is a naturally occurring species; on the other, its excessive numbers cause serious damage to both fisheries and the diversity of other birds. Last year's bird of the year title brought greater public attention to the cormorant and helped fuel debate over managing this species.