Collective action for the conservation of non-target species in the German Baltic Sea

The conservation of marine species not targeted by fishing is often limited to the designation of marine protected areas introduced through top-down government regulation such as the ASCOBANS treaty of 2016 or the EU Directive 2022/303. The reason for this exclusive top-down governance is that fisheries management is typically focused on managing target species, as the protection of non-target species comes with little or no economic benefit for fishers at high economic costs. Contrary to this general rule, a bottom-up voluntary agreement for the protection of harbour porpoise (phocoena phocoena) and diving sea ducks in the German Baltic Sea was signed by fisheries associations, a nongovernmental information centre (OIC), and Schleswig-Holstein’s Ministry of the Environment in 2013. Key measures include the reduction of gillnet lengths during summer, the use of the harbour porpoise warning device PAL, the establishment of an anonymous collection service for unintentionally caught porpoises, and dynamic (temporal, spatial) closures of fishing sites with high accumulations of sea ducks following a traffic-light system during winter. This research uses document analysis and stakeholder interviews to understand what motivated fishers to self-organise for the protection of non-target species and how conservation measures were enforced. It draws on a combination of the institutional analysis and development framework and social-ecological systems framework following the work of Cole et al. (2019) to trace the emergence of the voluntary scheme and assesses the performance of the agreement in terms of compliance and protection outcomes. To our knowledge, there is no research that investigates the contextual factors that allow or prevent self-organisation of actors in a common pool resource setting with the aim to protect a non-target species. This is particularly interesting because bottom-up collective action has the potential to address some of the common shortcomings of traditional, top-down designated marine protected areas, such as poor management and missing stakeholder involvement, and may thus constitute an alternative or sensible addition to existing top-down governance approaches. The research finds three major factors that shaped the protection efforts in the German Baltic Sea. First, the voluntary agreement was a reaction to avoid stricter formal coastal fishing regulations (Küstenfischereiverordnung). Second, advances in technology (PAL device) allowed the reduction of bycatch without restricting harvesting efforts, and third, fishers trusted the OIC as an intermediary between parties during the rulemaking and rule enforcement process. In terms of outcomes, we find that the agreement indeed reduces pressure on harbour porpoises and diving sea ducks in the area. Therefore, we conclude that voluntary, bottom-up schemes could be a sensible addition to existing top-down governance.