Project Description
The National Marine Fisheries Service contributes to the management of fisheries in various ways, including information relative to advisable size composition of catches and genetic effects of size selectivity. One of the projects of the Systemic Management Studies Program involves establishing advisable size composition of catches, using empirical information on the patterns in the size composition of non-human predator diets to adhere to established principles of management requiring the complexity of systems be accounted for completely.
Issues & Justification
The management of fisheries has been plagued by the difficulty of addressing all of the relevant management questions with a full accounting of the complexity of natural systems such as ecosystems. One of the issues involved in fisheries management involves the question of appropriate size composition of commercial catches. It is now recognized that various aspects of the harvesting process affects fish populations in a variety of ways; in particular, there are genetic effects of selectivity. Thus, size selectivity is an important aspect of fishery management; managers need to know what objectives should be established for appropriate (sustainable) size composition of commercial fish catches.
Goals
- To provide management advice regarding the most sustainable size composition of commercial fish harvests so as to adhere to the general principles of management.
- Publish the results in the peer-reviewed literature.
Methods
Data on the dietary habits of marine mammals has been extracted from the published literature and examined for patterns regarding the size composition of the prey consumed. Using this as empirical information regarding what is sustainable (what is normal and works in marine systems), the integrative nature of observed patterns serve as advice in the form of size composition required of commercial fish catches to adhere to the general principles of management.