Table 5.21. Effects of multiple gears on mixed
substrate habitat: summary of published studies. (S = statistically significant; citations in bold
print are peer-reviewed publications.)
| No. |
Reference |
Location |
Depth |
Sediment |
Effects |
Recovery |
Approach |
| 1 |
Auster et al. 1996 |
Coastal Gulf
of Maine, USA |
30-40 m |
Sand-shell |
S
more sea cucumbers and bottom depressions inside closed area. |
|
ROV
and video observations inside and outside an area closed to mobile gear for
10 yr. |
| 1 |
Auster et al. 1996 |
Coastal Gulf
of Maine, USA |
30-40 m |
Cobble-shell |
S
more emergent epifauna inside closed area. |
|
ROV
and video observations inside and outside an area closed to mobile gear for
10 yr. |
| 1 |
Auster et al. 1996 |
Stellwagen Bank, Gulf of Maine, USA |
20-55 m |
Sand with gravel and shell |
Disturbed
sand ripples and sand waves; dispersed shell deposits; absence of epifauna
and reduced microalgal cover in trawl and dredge tracks. |
|
Sidescan
sonar survey and ROV observations. |
| 2,3,4 |
Reise 1982;
Riesen and Reise 1982; Reise and Schubert 1987 |
Wadden Sea, The Netherlands |
<23 m |
Mud, coarse sand, and some pebbles |
Loss
of oyster and Sabellaria reefs; decrease in abundance of 28 species (mollusks
and amphipods); 23 “new” species (many of them polychaetes). |
|
Compared
benthic surveys conducted during time period when oysters were overexploited
and trawl fishery developed on Sabellaria reefs (1869-1986). |
| 5 |
Thrush et al. 1998 |
Hauraki Gulf, New
Zealand |
17-35 m |
Mud and sand |
S reductions in density of large epifauna, echinoderms, and
long-lived surface dwellers; S increases in density of small, opportunistic
species; some predictions contra-indicated by results; 15-20% variability in
macrofaunal community composition attributed to fishing pressure. |
|
Tested 10 predictions of the effects of increasing fishing
intensity on benthic community structure by comparing samples and video
images from 18 stations exposed to
varying degrees of commercial fishing pressure by bottom trawls, Danish
seines, and scallop dredges. |
| 6 |
Valentine and Lough 1991 |
Eastern Georges Bank |
|
Sand and gravel |
Trawl
and dredge tracks in sediments; sparse epifauna, gravel mounds, and smoother
bottom in disturbed areas. |
|
Sidescan
sonar and submersible observations of area presumed to be disturbed by trawls
and scallop dredges. |