COVID-19 lockdown reveals tourists as seabird guardians

The widespread lockdowns put in place to limit the spread of the new coronavirus disease (COVID-19) offers a rare opportunity in understanding how human presence influence ecosystems. Using data from long-term seabird monitoring, we reveal a previously concealed guarding effect by tourist groups on an iconic seabird colony in the Baltic Sea. The absence of tourists in 2020 lead to a sevenfold increase in presence of white-tailed eagles Haliaeetus albicilla, a sevenfold increase in their disturbance of breeding common murres Uria aalge and causing 26% lower murre productivity than the long-term average. Eagles did not prey on murres, but their frequent disturbances delayed egg laying and facilitated egg predation from herring gulls Larus argentatus and hooded crows Corvus cornix. Based on our findings, we suggest that human presence could be used as a strategic measure in guarding seabird colonies, and that a social-ecological systems perspective is vital for long-term success in protected area management.

Automated summary

The lockdowns during the COVID-19 pandemic provided a rare opportunity to observe the impact of human presence on ecosystems, with a study revealing a previously concealed guarding effect by tourist groups on a seabird colony in the Baltic Sea. The absence of tourists in 2020 led to increased presence of white-tailed eagles, higher disturbance of breeding common murres, and lower murre productivity compared to the long-term average. The findings suggest that human presence could be utilized as a strategic measure in protecting seabird colonies.