The current management of the blue crab stock in Chesapeake Bay is a case study of the application of the Bay Program’s Decision Framework.
Officially adopted by the Program in 2012, the framework is designed to implement effective adaptive management for all Bay Program activities. The process of setting explicit goals, developing well-informed management strategies, carefully monitoring and assessing system response to those strategies, and then adapting management based on what is learned is exemplified by the present crab management.
The blue crab abundance outcome statement in the new draft Bay agreement is the current goal of Bay crab management. As explained below, present and future efforts to achieve the outcome follow the basic outline of the decision framework.
Blue Crab Abundance Outcome
Maintain a sustainable blue crab population based on the 2012 target of 215 million adult females and continue to refine population targets through 2025 based on best available science.
- Articulate Outcome: Important characteristics are that the goal be explicit, measurable and time bound. This goal provides two performance metrics: maintenance of a sustainable population and continued refinement of the population target. Both of these are measurable/observable, and they are time-bound in the sense that “sustainable” and “continue” imply immediate and constantly iterating efforts.
- Describe Factors Influencing Outcome Attainment: The science behind the outcome recognizes that in addition to fishing pressure, habitat quality, recruitment success and predation all potentially affect the maintenance of a sustainable population.
- Assess Current management Efforts: At present, the primary management effort is controlling fishing pressure. While the Chesapeake Total Maximum Daily Load is aimed at increasing habitat quality — more SAV and less hypoxia — there are no other specific efforts aimed at blue crabs.
- Develop a Management Strategy: The current strategy is refined management of fishing pressure, specifically fishing pressure on overwintering female crabs. Further efforts to manage commercial and recreational fisheries may be necessary to achieve the outcome. Additional habitat management efforts may also be necessary (e.g. sanctuaries).
- Develop a Monitoring Program: The current monitoring of the overwintering population of females is excellent. Monitoring of the commercial and recreational fisheries’ pressure is less robust. The current population drop occurred despite the existence of ample female crabs. This is evidence that other factors (e.g. habitat quality, recruitment, predation) are also very important for sustaining the target population. It will be necessary to monitor those factors to learn what additional management efforts might be necessary.
- Assess Performance: Managers have already concluded that the current management effort, in terms of a minimum of 215 million female crabs, is obviously insufficient to ensure a sustainable population.
- Manage Adaptively: The assessment that the current management strategy is insufficient will motivate a reassessment of the understanding of critical factors and the management strategies designed to address those factors. Revised strategies and targets should be the adaptive response.
The challenge confronting the Bay Program as it moves to articulate new goals and desired outcomes is to structure those statements and the supporting management strategies so they reflect the same basic logic evidenced in the crab management effort.
A key to establishing the framework for learning and improving management is to make explicit the reasons for undertaking any action.
When the outcome, in terms of the change in existing conditions or procedures, is clear it becomes possible to assess management efforts and determine whether continuation is justified. The important question is not “what are we doing?” but “why are we doing it?”
Once the work under the new agreement is framed in this way, the Bay Program will be positioned to continually improve its efforts to improve the Bay and provide increased transparency and accountability for the public.