This is the ASCOBANS species action plan for what is called Baltic harbour porpoise population primarily inhabiting the Baltic Proper. The population’s abundance has recently been estimated at only 497 individuals (95% CI 80 –1091) and it has a wide overall distribution range. During the winter season, it stretches from the Åland and Archipelago Seas in the north, to the Southern Baltic Proper in the southwest, and perhaps even further west thereof. In the summer season, however, when calving and mating take place, the majority of the population aggregates at and around the Hoburg’s and Northern and Southern Mid-sea banks in the Baltic Proper. Thus, this area should be considered essential and probably the main breeding area for the Baltic harbour porpoise population. The population’s current status calls for immediate conservation actions. Bycatch in gillnet fisheries has been recognized as the primary threat for the survival of the Baltic harbour porpoise population, although high contaminant levels are also of serious concern. Continuous and impulsive underwater noise and possibly also reduced prey quality are further contributing factors.
The Jastarnia Plan serves as a framework for international collaboration towards achieving ASCOBANS’ interim goal of restoring the population to at least 80per cent of carrying capacity, and, ultimately, a favourable conservation status for Baltic harbour porpoises. The plan lists a number of actions, of which the following should be carried out as a matter of urgency:
1.Involve stakeholders, use alternative fishing gear, apply available technology such as pingers, and reduce or eliminate fishing effort to reduce the number of bycaught harbour porpoises in the Baltic towards zero.
2.Designate marine protected areas for harbour porpoises together with management plans and monitoring schemes for efficient contribution to the protection and monitoring of the population.
3.Minimize the impact of anthropogenic underwater noise through the use of available mitigation measures and implementation of internationally harmonized national threshold limits and guidelines.
The outline of the Plan is as follows:
1.Introduction: An outline of the scope, context and policy setting of the Plan, including information on previous conservation management actions, as well as overall objectives.
2.Legal frameworks: A list of relevant legal frameworks, including international conventions and agreements, European and national legislation and management arrangements.
3.Governance: An outline of the management structure identifying the roles, responsibilities and interactions between the key stakeholders, as well as the timeline from the development stage through the implementation and review stages.
4.Scientific background: Information on biology, status, environmental parameters, critical habitats, and attributes of the population to be monitored.
5.Threats, mitigation measures and monitoring: A summary of the known or suspected threats together with a discussion of their evidence of impact, and the mitigation measures for the key threats and how they will be monitored.
6.Actions: Descriptions of actions including information such as concise objective, rationale, activity or method, timeline, actors and priority.