South Atlantic MPA: pre-closure evaluation of habitat and fish assemblages in five proposed reserves

The South Atlantic Fisheries Management Council (SAFMC) has proposed implementation of nine marine protected areas (MPAs) between Cape Hatteras, NC and the Florida Keys to protect seven species of grouper and tilefish, all members of the deepwater snapper-grouper complex. Based on recent stock assessments, four of these are considered to be overfished including snowy grouper (Epinephelus niveatus), warsaw grouper (E. nigritus), speckled hind (E. drummondhayi), and tilefish (Lopholatilus chamaeleonticeps). Yellowedge grouper (E. flavolimbatus) are not considered overfished, and the status of misty grouper (E. mystacinus) and blueline tilefish (Caulolatilus microps) is unknown at this time. Life history characteristics of several of the targeted species make them more vulnerable to overfishing. Many are protogynous hermaphrodites with highly female-skewed ratios, even in unfished populations.

Aggregate spawning with strong interannual site fidelity is also common, offering knowledgeable fishermen the possibility to harvest large numbers of reproductively active fish in a short period of time. Dominant males aggressively defend these spawning aggregation sites and are more easily caught than during non-spawning periods, leading to further skewing of the sex ratios. The National Marine Fisheries Service has volunteered to conduct preliminary investigations of the proposed MPAs and then to evaluate the efficacy of the closures once they have been made. A project was designed to examine five of the proposed MPAs with three main objectives:

1) establish baseline estimates of species composition and fish abundance, especially for species of grouper and tilefish

2) describe habitat features

3) document the relationship between habitat and species assemblages

Four of the nine proposed MPA sites were not included for this project, two artificial reef sites in the South Atlantic Bight and two sites off extreme southern Florida. The artificial reef sites were excluded because the project focused on fish-habitat relationships in natural areas. The south Florida sites were excluded for logistical reasons related to their remoteness from the remaining five natural habitat sites in the South Atlantic Bight. Gear employed during the surveys included a remotely operating vehicle (ROV), a stationary video camera array, and chevron fish traps. Three of the seven targeted reef fish (snowy grouper, speckled hind, and blueline tilefish) were observed in the first year of the survey (2004). Species composition varied between proposed MPAs, but all were dominated by small reef fish of limited commercial or economical importance. Fish densities differed among the habitats observed. Grouper were most abundant on rock outcrops, especially those of higher relief, while tilefish were most abundant on flat pavement habitat and low relief outcrops. One surprising result was the abundance of lionfish (Pterois volitans), an invasive species native to the Indo-Pacific. Like groupers, lionfish are structure-oriented and were most abundant on high relief outcrops. Grouper, lionfish, and tilefish displayed a latitudinal decrease in density from north to south. A cruise similar to the one presented in this report has been funded for 2005 and subsequent annual cruises are planned through 2012. This study presents a unique opportunity to examine proposed MPA sites before implementation of fishing restrictions, thus providing fishery managers with robust baseline data upon which efficacy evaluations of closures can be made

To Obtain estimates of reef fish reef fish density and species composition density associated with bottom features within and outside the preferred proposed MPAs.

To describe habitat features habitat features within and outside the preferred and proposed proposed MPAs.

Document the relationship relationship between habitat and species assemblages.

South Atlantic MPA: pre-closure evaluation of habitat and fish assemblages in five proposed reserves

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