Project Proposal Title: Developing Biochemical And Physiological Predictors Of Long Term Survival In Released Blue Sharks

For catch-and-release sports fishing and non-retention of commercially caught fish to be justifiable management options, there must be a reasonable likelihood that released fish will survive long term. At present, there is no scientific basis for making this prediction for any large pelagic fish. Therefore, even when recreational anglers and commercial fisherman practice good catch-and-release fishing, high rates of delayed mortality are a distinct possibility. Tag-and-release programs are important tools to assessing post-release survival, but they can be difficult and expensive to implement. Conclusions from tag-and-release studies are rarely extrapolated to other species because of the many factors (e.g. size, water temperature, fight time and fishing gear) that may influence survivability or mortality. We propose a novel approach to study the basis of post-release mortality. Rather than assessing how many fish survive, we try to understand why fish die. We are developing a set of diagnostic tools to assess the biochemical and physiological status of sharks caught by long line on scientific cruises. These tools are being developed in combination with pop-off satellite archival tag (PSAT) data to establish predictors of survival. We have focused on assessing the extent of tissue damage arising from capture using comprehensive analyses of ions, metabolites and proteins found in the plasma (discussed in detail in our proposal). For example, the damage to myocardial tissue upon a heart attack causes release of proteins such as creatine phosphokinase and troponin I into the plasma. We are also using the properties of blood cells themselves to assess the extent of systemic oxidative damage. Under stressful conditions, a series of genes are induced leading to synthesis of mRNA and protein corresponding to the heat shock proteins (hsp). We have used hsp70 induction in a number of fish models as an index of cellular damage. 2. Progress during FY 2003. Provide a thorough discussion of accomplishments and problems