Lindholm et al.: Ecological effects of bottom trawling on fish habitat along the central California outer continental shelf 
93 
Malecha and Stone (2009) found that recovery of sea 
whips damaged by trawling was limited. 
We focused on the potential impacts of bottom trawl- 
ing with small-footrope gear on fish habitat on the sea- 
floor off central California. In the context of ongoing 
efforts to understand and manage fishing impacts (Din- 
more et ah, 2003; Hannah, 2003; Bellman et ah, 2005; 
Ellis et ah, 2008; Hourigan, 2009; de Juan and Lieon- 
art, 2010), the results of our study indicate that bottom 
trawling with small-footrope gear may have limited im- 
pacts in sandy habitats of the outer continental shelf 
in California. Although the global literature clearly in- 
dicates that communities on hard substrates are more 
vulnerable to bottom trawling (see reviews in Dayton 
et ah, 1995; Kaiser et ah, 1998; Watling and Norse, 
1998; NRC, 2002; Barnes and Thomas, 2005), the lack 
of impacts to unconsolidated sandy sediments at a 
depth of 170 m as observed in this study indicates that 
this type of sediment is much less vulnerable, at least 
at the level of fishing effort undertaken for this study 
with a bottom trawl that met the federal requirement 
of a small footrope ( <20 cm in diameter). Identification 
of habitats and depth zones appropriate for bottom 
trawling in the “working seascape” among closed areas 
will be important for efforts to balance regulations of 
local seafood and fish landings and the needs of fisher- 
men’s livelihoods with environmental impacts of trawl- 
ing across the continental shelf and slope habitats. 
Acknowledgments 
Generous support for this project was provided by the 
California Ocean Protection Council through a State 
Coastal Conservancy Grant to The Nature Conservan- 
cy (SCC grant no. 10-058), private donations from the 
Kabcenell Family Foundation and the Seaver Institute, 
and contributions from the James W. Rote Professor- 
ship and the Undergraduate Research Opportunities 
Center at California State University Monterey Bay. 
We thank the many students who participated through- 
out this study (including J. Derbonne, who passed away 
before the completion of the project). For key support 
in the field, we recognize the captains and crews of the 
FV Donna Kathleen, FV South Bay, and RV Fulmar 
and the ROV team from Marine Applied Research and 
Exploration. We also thank staff from NOAA Fisheries, 
the West Coast Groundfish Observer Program, and the 
Morro Bay Harbormaster’s Office. Suggestions provided 
by 3 anonymous reviewers improved the manuscript. 
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