Asch and Collie: Changes in a benthic megafaunal community due to disturbance from bottom fishing 
455 
November 2000 research cruise may be responsible 
for the low densities of certain species (e.g., sponges) 
observed during that year. Overall, an extended period 
of monitoring is needed to determine which epifaunal 
species will be most abundant in CA-II once recovery 
is complete. 
In conclusion, the cover of hydroids, bushy bryozo- 
ans, sponges, and F. implexa was generally higher at 
sites undisturbed by mobile fishing gear, although the 
magnitude and significance of this effect depended 
on water depth and differed between years. Among 
colonial epifauna taxa, only encrusting bryozoa are 
positively affected by bottom-fishing disturbance. The 
species of colonial epifauna and noncolonial megafauna 
that are more abundant at undisturbed sites generally 
possess characteristics that make them vulnerable to 
the effects of mobile fishing gear. These characteristics 
include emergent growth forms, soft body parts, low 
motility, use of structurally complex microhabitats, 
long life spans, slow growth, and larval dispersion over 
short distances. Following the prohibition on bottom 
fishing in CA-II, both colonial (i.e., sponges and bushy 
bryozoans) and noncolonial (i.e., P. magellanicus, S. 
droebachiensis, Pagurus spp., Asterias spp.) organisms 
increased in abundance. Although research investigat- 
ing the long-term recovery of epifauna from bottom- 
fishing disturbance is ongoing in the other areas of 
the Gulf of Maine (e.g., Stellwagen Bank and western 
Gulf of Maine closed area), this study is one of the 
first in the region to track the recovery of the colonial 
epifaunal community from disturbance for a period 
extending beyond two years. The fact that it took most 
taxa two years or more to initially respond to the ces- 
sation of bottom fishing indicates that even infrequent 
trawling can alter benthic communities for years to 
come. When monitoring of CA-II was first initiated, 
it was predicted that it would take 5-10 years for the 
megafaunal community to recover (Collie et al., 1997). 
After six years of studying transects inside CA-II, we 
conclude that recovery does not yet appear complete 
and that the higher end of this projection may prove 
more accurate. 
Acknowledgments 
Funding was provided by the National Oceanic and 
Atmospheric Administration/University of Rhode Island 
Cooperative Marine Education and Research Program, 
United States Geological Survey, National Undersea 
Research Center, and National Sea Grant College Pro- 
gram. P. C. Valentine and D. Blackwood of the U.S. 
Geological Survey greatly contributed to this research 
by operating the SEABOSS and providing access to the 
benthic photographs collected with this instrument. G. 
Escanero, J. Hermsen, E. Hughes, and L. Hunke are 
acknowledged for analyzing benthic photographs taken 
between 1994 and 1998. This manuscript has been 
greatly improved by suggestions from C. Oviatt, G. For- 
rester, J. DeAlteris, and three anonymous reviewers. 
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