Benthic Habitats and the Effects of Fishing

Symposium Abstract: The Ocean Habitat Protection Act: Overdue Protection for Structurally Complex Seafloor Habitats

H. Gillelan

doi: https://doi.org/10.47886/9781888569605.ch150

Until the mid-1980s, bottom trawls were used only on relatively flat ocean bottoms where the net would not snag on vertical structures such as corals, boulders, shipwrecks, and rock pinnacles. Large, heavy roller and rockhopper gear now enables bottom trawls to access areas of the oceans that were previously safe havens for marine life and fragile habitats. There is increasing scientific consensus that trawling in structurally complex habitats is one of the most destructive types of bottom fishing because of the long-term damage it causes to the diversity, species abundance, and ecological processes dependent on these habitats. Commercially and recreationally important fish, such as rockfish, haddock, Atlantic cod, snappers/groupers, and American lobster, and other types of marine life depend on structurally complex habitat during different stages of their lives. The young of species can show far greater survival rates where the seabed is complex. Where bottom structure has been damaged by bottom trawlers, diversity and the health of fish populations are negatively impacted. The Ocean Habitat Protection Act, by limiting roller and rockhopper gear to an 8-inch diameter, would protect these essential, structurally complex habitats by removing the gear that allows access to the habitats. Many states and several federal Fishery Management Councils have passed regulations that have begun to address this threat by restricting use of this gear in designated areas or fisheries. However, the patchwork of existing regulations often applies only to certain fisheries and leaves unprotected large areas of sensitive deep-sea corals, sponge beds, and other aggregations of geologic and biogenic structures. The restriction proposed by this bill is one shown to have been effective at reducing trawling in these habitats on the West Coast. Implementation of this gear restriction would maintain biodiversity and healthy seafloor habitats, and would assist many depleted species in recovery to sustainable levels.