Studying Seafloor Habitat Recovery Following the Cessation of Fishing Along the Coast of California

Principal Investigator:: James Lindholm, Ph.D., Pfleger Institute of Environmental Research; Andrew DeVogelaere, Monterey Bay National Marine Sanctuary
Timeline:: Initiated June 2006, on-going.

Fish use the features of the seafloor as well as epifauna (animals attached to the substrate) as refuge from predators and strong ocean currents.

Mobile fishing gears are currently in use throughout all the worldís major oceans, including the Pacific coast of California. While much has been learned about how various fishing gears impact the seafloor, comparatively little is known with respect to the recovery of seafloor habitats and associated taxa following the cessation of fishing. Yet it is precisely this information that is critical to the managers of the Monterey Bay, Cordell Bank, and Gulf of the Farallones National Marine Sanctuaries, as well as other Federal and state agencies, to insure a truly ecosystem-based approach to management. Developing information to address this issue has been identified as a high priority for four of the five west-coast sanctuaries, based on a recent evaluation of information needs for the Sanctuary Program.

One of the primary challenges to the study of seafloor habitat recovery is the lack of adequate control areas (areas not impacted by fishing) in which to conduct studies. Absent control sites, there is no opportunity to compare areas recovering from fishing impacts to areas that continue to be impacted by fishing. While the number of closed areas designed for scientific research is limited, there have been a number of areas closed to fishing by management actions that provide scientists an opportunity to conduct habitat-related research. The recent closures along the coast of California present such an opportunity. The closures were identified as part of the Final Preferred Alternative for the Groundfish Essential Fish Habitat (EFH) Environmental Impact Statement produced by the Pacific Fishery Management Council. These closures exclude all trawling along the seafloor.

map of essential fish habitat area

In this on-going study, recovery of previously fished sites within an EFH closure in the vicinity of Cordell Bank will be monitored over time, and will be compared to sites of comparable habitat type that continue to be fished outside the closure area to the south, adjacent to the Farallon islands.

The sampling framework will consist of a paired factorial design that will test for differences in targeted response variables between 10 stations within the closure area and 10 stations that continue to be actively fished outside the closure. Additionally, water depth will also be investigated as a factor within the closure/fished treatments. The primary response variables at each station will include 1) seafloor microhabitats, 2) epi-faunal macro-invertebrates, and 3) in-faunal macro-invertebrates. Data will also be collected on fishes at each site.


DOER Marine’s remotely operated vehicle (ROV) X2, was configured to take down- and forward-looking still photographs as well as video during the June 2006 research cruise.	Photo of sea whips (subclass Octocorallia) taken with the downward facing camera on the X2 ROV

This project is a collaboration between PIER, the Monterey Bay National Marine Sanctuary, and the National Centers for Coastal Ocean Science (NCCOS). Support for the project is provided by the Sanctuary and NCCOS.