Dolphin off Topsail Island, NC

Concluding a health assessment of Pinfish

Building the foundation for future health monitoring

Previously we posted about our collaborative field efforts to collect baseline data for future health assessments of pinfish in North Carolina . Led by Veterinary student Sara Collins and Dr. Greg Lewbart at NC State College of Veterinary Medicine, with the assistance of NCSM's Dr. Dan Dombrowski and our own intern Joe Flores, we are happy to announce that this project is now completed! The full manuscript can be read here.

Why this matters

Collecting baseline data for monitoring the health of populations of fish like pinfishes is incredibly important at this point in time. The oceans are changing rapidly, and we don’t know how every species will respond to changes in temperature, pollution, the spread of non native species, and changes in ocean acidity. But how do we know when fish populations are stressed or unhealthy? Blood chemistry and hematological parameters are incredibly useful for monitoring the health of wild populations, in particular populations of marine animals. The same way that your doctor uses counts to check for your “baseline levels”, we can rapidly survey physiological changes in a minimally invasive manner in marine fishes. Simply catching a sample of fishes and doing a small blood extraction before release holds incredible promise for marine conservation efforts.

The catch? You need to know what healthy values are. Enter our study.

We establish new baseline data for pinfishes, building on prior research that was begun over 4 decades ago. Why pinfish? Believe it or not, these little fish are of high importance in nearshore marine food webs. They can occur at densities so high that they alter the invertebrate community across entire estuaries. Pinfish also make up a large portion of the prey base for several larger game fish and sharks. Therefore, changes in the health of fish like pinfish could cause cascading effects across an ecosystem.

Pinfish are also fairly interesting in their own right. A study by another research group found that these fish come in two types or “ecomorphs”: (1) a sand specialist with a downward facing mouth and (2) a seagrass specialist with a forward facing mouth. We compared our baseline data between these morphs to assess whether feeding mode changes baseline health data values. The short answer is that it doesn’t appear to. Now the caveat is that our study was restricted to adults in one mixed habitat area where both morphs occur. Further work will be needed to see if there isn’t fine scale variation, but overall our study provides a wealth of new data that can be used to further refine new baseline data and will aid in monitoring the health of these very important coastal fishes.

Dialogue & Discussion