Identifying priority areas for conservation to promote connectivity and mitigate the impacts of anthropogenic disturbance.

As nations seek to expand protected area (PA) networks to cover 30% of land and seas by 2030 (30×30), there is an urgent need for systematic conservation planning and spatial prioritization that considers the broad range of ecological and socioeconomic factors influencing the persistence of biodiversity. A remaining challenge in spatial prioritization is identifying areas that not only contribute to ecological connectivity but also are vulnerable to isolation and connectivity decline caused by anthropogenic disturbance. We devised an approach to assess PA networks and prioritize areas for conservation action and applied it to the Swedish coastal Baltic Sea area as an example. We developed connectivity models for 16 key fish species to identify habitats that provide the greatest contributions to maintaining network connectivity. We then incorporated spatial data on anthropogenic disturbance into the connectivity models to identify habitats for which human activities may hinder dispersal and recruitment, making them vulnerable to local population declines. We assessed the adequacy of the marine protected area (MPA) network in protecting these biodiversity features. Using spatial prioritization with explicit objectives to protect these biodiversity features, we then identified important areas for future protection. Although the Swedish MPA network provided a reasonable level of protection for these key habitats, their protection in stricter MPA categories (International Union for Conservation of Nature categories Ia, Ib, and II) was poor. Expanding the MPA network from its current coverage (10.5% of the study area) to 11%, the mean protection level across features increased from 25% to 48%. Expanding to 15% coverage increased mean protection across features to over 90%. Our approach to conservation planning incorporated not only biodiversity data (e.g., habitats and connectivity) but also the pressures these elements of biodiversity are susceptible to from human activities.