Why is collecting blood from pinfish important? Glad you asked! Monitoring the health of wild populations is of essential utility if we are to assess the impacts of factors such as pollution, changes in fishing practices, or habitat alteration. Unfortunately, health assessments of marine fish populations are severely lacking, particulary for fishes of limited commercial importance. This is problematic since these fishes often form an important part of the diet of commercially important fishes or animals of conservation concern. In the case of the pinfish, these bait stealing fishes are a favorite food item to our lovable friends the dolphins. Hematology represents a useful tool for the monitoring of the health of a population. However in order for these values to actually be useful, species specific values have to be established to assess potential changes. This is where we come in.
Hosted by Greg Harms at CMAST , we joined Sara Collins and Dr. Kim Thompson in a rapid effort to collect enough pinfishes to complete this study. We initially headed out east of Morehead city attempted to collect fishes using a large 50’ seine. We encountered a pretty impressive diversity of fishes, including halfbeaks, tonguefishes, stingrays, oyster toadfishes, and blennies. However, seining proved to be problematic in yielding fishes of sufficient size from which to obtain blood values. Not to be discouraged, we returned to Morehead City, switched to angling, and managed to obtain enough fishes to complete the required sampling for the study.
In addition to collecting blood samples, we are also following up on a study that by Ruehl et al. who found differences in pinfish morphology corresponding to habitat type . The area we collected in has two types of habitat, suggesting that we may also have two different ‘morphs’ of pinfishes. Ruehl et al. suggest that these morphs have different levels of activity which could influence our hematological values. To account for this possibility, each specimen we collected will be digitized and assessed for morphological changes as in Ruehl et al. From this we will be able to test whether potential changes in morphology are correlated with changes in hematological values. Stay tuned for more updates as the study progresses!