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Providing evidence to improve practice

Individual study: The environmental impacts of three different queen scallop (Aequipecten opercularis) fishing gears

Published source details

Hinz H., Murray L.G., Malcolm F.R. & Kaiser M.J. (2012) The environmental impacts of three different queen scallop (Aequipecten opercularis) fishing gears. Marine Environmental Research, 73, 85-95


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use an otter trawl instead of a dredge Subtidal Benthic Invertebrate Conservation

A replicated, controlled, study (date of study not reported) in a sandy area in the north Irish Sea, Isle of Man (Hinz et al. 2012) found that an otter trawl caught fewer unwanted invertebrates and fish (combined), and a different unwanted catch species composition, compared to two dredge designs. The otter trawls caught fewer unwanted invertebrates and fish (4 individuals/1,000 m2) than the two dredge types (23–59 individuals/1,000 m2). In addition, overall unwanted catch species composition was different between the otter trawl and the two dredges (species composition data presented as graphical analyses). Unwanted otter trawl catch was reported to be dominated by fish, whereas unwanted dredge catch was dominated by invertebrates. Following fishing with either gear, there were no changes in total invertebrate abundance and biomass living in or on the sediments (raw data not presented). The otter trawl caught similar amount of commercially targeted queen scallops Aequipecten opercularis (45 scallops/1,000 m2) compared to the dredges (15–48 scallops/1,000 m2). Three queen scallop fishing gears were compared: an otter trawl, a new dredge design, and a traditional Newhaven dredge. The study site was subdivided into 12 trawling lanes (40 m wide, 1 nm long) in 20–23 m water depth. Each fishing lane was allocated to one gear design (4 lanes/design). Commercial and unwanted catches were sorted, identified, counted and weighed. Before, and seven days after fishing trials, invertebrates (size unspecified) were sampled in each lane using a 2-m beam trawl (5-min tow; 6 tows/lane) and a sediment grab (0.1 m2; 6 grabs/lane).

(Summarised by Anaëlle Lemasson & Laura Pettit)

Modify the design of dredges Subtidal Benthic Invertebrate Conservation

A replicated, controlled, study (date unspecified) in an area of sandy seabed in the north Irish Sea, Isle of Man (Hinz et al. 2012) found that a new design of scallop dredge caught similar species of unwanted invertebrates and fish, but in lower amounts, compared to a traditional scallop dredge. Overall unwanted species composition (invertebrates and fish) was similar between the new and the traditional dredge (composition data presented as graphical analyses). Unwanted catch from both dredges was reported to be dominated by invertebrates. The new dredge design caught fewer unwanted invertebrates and fish (23 individuals/1,000 m2) than the traditional dredge (59). In addition, following fishing impacts, there were no changes in total invertebrate abundance and biomass living in or on the sediments for any of the gears (raw data not presented). The new dredge design caught similar amount of commercially targeted queen scallops Aequipecten opercularis (48 scallops/1,000 m2) compared to the traditional dredge (15). Two queen scallop dredges were compared: a new dredge design with a rubber lip instead of traditional teeth, and a traditional Newhaven dredge. The study site was subdivided into eight trawling lanes (40 m wide, 1 nm long) in 20–23 m water depth. Each fishing lane was allocated to one gear design (4 lanes/design). Commercial and unwanted catches (invertebrates and fish) were sorted, identified, counted and weighed. Before, and seven days after fishing trials, invertebrates (size unspecified) were sampled in each lane using a 2-m beam trawl (5-min tow; 6 tows/lane) and a sediment grab (0.1 m2; 6 grabs/lane).

(Summarised by Anaëlle Lemasson & Laura Pettit)