Testing the efficacy of lionfish traps in the northern Gulf of Mexico

PLoS One. 2020 Aug 26;15(8):e0230985. doi: 10.1371/journal.pone.0230985. eCollection 2020.

Abstract

Spearfishing is currently the primary approach for removing invasive lionfish (Pterois volitans/miles) to mitigate their impacts on western Atlantic marine ecosystems, but a substantial portion of lionfish spawning biomass is beyond the depth limits of SCUBA divers. Innovative technologies may offer a means to target deepwater populations and allow for the development of a lionfish trap fishery, but the removal efficiency and potential environmental impacts of lionfish traps have not been evaluated. We tested a collapsible, non-containment trap (the 'Gittings trap') near artificial reefs in the northern Gulf of Mexico. A total of 327 lionfish and 28 native fish (four were species protected with regulations) recruited (i.e., were observed within the trap footprint at the time of retrieval) to traps during 82 trap sets, catching 144 lionfish and 29 native fish (one more than recruited, indicating detection error). Lionfish recruitment was highest for single (versus paired) traps deployed <15 m from reefs with a 1-day soak time, for which mean lionfish and native fish recruitment per trap were approximately 5 and 0.1, respectively. Lionfish from traps were an average of 19 mm or 62 grams larger than those caught spearfishing. Community impacts from Gittings traps appeared minimal given that recruitment rates were >10X higher for lionfish than native fishes and that traps did not move on the bottom during two major storm events, although further testing will be necessary to test trap movement with surface floats. Additional research should also focus on design and operational modifications to improve Gittings trap deployment success (68% successfully opened on the seabed) and reduce lionfish escapement (56% escaped from traps upon retrieval). While removal efficiency for lionfish demonstrated by traps (12-24%) was far below that of spearfishing, Gittings traps appear suitable for future development and testing on deepwater natural reefs, which constitute >90% of the region's reef habitat.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Biomass
  • Conservation of Natural Resources / methods*
  • Coral Reefs
  • Ecosystem
  • Environmental Restoration and Remediation / methods*
  • Fishes / growth & development
  • Gulf of Mexico
  • Introduced Species / trends*
  • Perciformes / growth & development
  • Population Density
  • Population Dynamics
  • Predatory Behavior

Grants and funding

Financial support for this research was provided by the Florida Fish and Wildlife Conservation Commission (Grant No. 13416 to R. N. M. Ahrens and H. E. Harris). Support for H. E. Harris was provided by the National Science Foundation Graduate Research Fellowship Program (Grant Nos. DGE-1315138 and DGE-182473). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Opinions, findings, or conclusions expressed in this document do not necessarily reflect the views of our supporting organizations.