A novel bycatch reduction device (BRD) and its use in a directed fishery for non-indigenous green crabs (C. maenas) in Atlantic Canada

  • Published source details Poirier L.A., Tang S., Mohan J., O’Connor E., Dennis E., Abdullah M., Zhou D., Stryhn H., St-Hilaire S. & Quijón P.A. (2018) A novel bycatch reduction device (BRD) and its use in a directed fishery for non-indigenous green crabs (C. maenas) in Atlantic Canada. Fisheries Research, 204, 165-171.


This study is summarised as evidence for the following.

Action Category

Modify fishing trap/pot configuration

Action Link
Marine Fish Conservation
  1. Modify fishing trap/pot configuration

    A replicated, paired, controlled study in 2016 of four seabed sites in the Gulf of St. Lawrence, Canada (Poirier et al. 2018) found that modifying a fyke net reduced the capture of unwanted American eel Anguilla anguilla and winter flounder Pseudopleuronectes americanus compared to unmodified, conventional fyke nets, and the overall number of unwanted species (fish and invertebrates) in catches decreased. Across sites, catch numbers of unwanted eel and flounder (the two main unwanted fish species caught) were lower in modified nets (eel: 3, flounder: 7) than unmodified nets (eel: 37 fish, flounder: 43). The species composition (fish and invertebrates) was different between nets (for fish, flounder and mummichog Fundulus heteroclitus accounted most for the reduced catch in modified nets) and the number of unwanted species was lower in modified nets (modified: 5 species, unmodified: 12 species). In addition, numbers of target catch of green crab Carcinus maenas were reduced in modified nets (modified: 1,791, unmodified: 6,637). Data were collected at four sites in Murray Harbour off Prince Edward Island in July 2016. At each site, a removable ‘bycatch reduction device’ was randomly assigned to one of two conventional fyke nets (used to target green crab) and both nets set 100 m apart for three sets of four consecutive 24 h deployments, the device being switched between nets/set. After each individual 24 h deployment, fyke nets were fished at low tide. The ‘bycatch reduction device’ consisted of a sloped barricade ramp attached to a removable hoop with an entrance slit designed to prevent entry of non-target species (see paper for gear specifications).

    (Summarised by: Natasha Taylor)

Output references
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