Trap Building InstructionsConference PosterProject Summary VideoVideos of DeploymentsPrevious Trap ResearchField Testing Summary
This project was funded through NOAA's Saltonstall-Kennedy Competitive Grants Program, to study the effectiveness of lionfish traps on deep reefs in the Florida Keys. These non-containment lionfish traps (Gittings traps) do not use bait and are designed specifically to attract lionfish, which prefer to live near structure and manmade objects. Traps of this type of design are beneficial because they reduce bycatch and eliminate the risk of abandoned fishing traps, also known as "ghost traps." This project built upon previous experience from several organizations and individuals, including Dr. Steve Gittings of NOAA, who originally designed the traps.
Throughout the course of the project, REEF collaborated with partners including Florida Fish and Wildlife Conservation Commission (FWC), Dr. Steve Gittings, Alex Fogg (Coast Watch Alliance), Dr. Holden Harris (University of Florida) and Lionfish University. We also utilized the expertise of the Florida Keys lobster fishing community to provide insight to improve trap design and catch rates. The goal of the project was to determine whether the Gittings lionfish (Noncontainment) traps are an effective and viable fishing method to target lionfish populations in deep water in the Florida Keys in habitats that are not able to be accessed by recreational divers.
The project is funded through NOAA’s Saltonsall-Kennedy Grant Program and all activities were conducted under Florida Keys National Marine Sanctuary (FKNMS) Permit.
Gittings Trap Design
The project required substantial gear and method field testing to improve the Gittings trap design to reduce risk of sea turtle and habitat entanglement and improve deployment success of the Gittings trap. Different modifications were field tested to reduce the risk while ensuring lionfish capture success and trap deployment success.
Tested Designs
Detailed instructions on how to build the final trap from this project can be found below.
Instructions on How to Build a Weldless Gittings Trap
To reduce entanglement risks of the Gittings, which had been a previous issue described in a study in the Gulf of Mexico with a sea turtle entanglement, we replaced loose netting with a hard plastic lattice on the bottom of the trap to create a ceiling to eliminate the trap from inverting on itself if something crawled underneath. We had no entanglements of sea turtles or other endangered species despite their presence during the testing of the traps throughout the duration of the study.
Videos of Deployments
Gittings Trap deployment success was highly dependent on environmental conditions, weight and flotation.
Initially traps were deployed with a surface float however numerous failures due to boat snags encouraged the team to switch to subsurface floats.
Video Setting the Subsurface Float
Unfortunately the subsurface floats impacted the traps ability to open with habitat contact and therefore in order to complete the scheduled paired field testing to determine lionfish capture rates in Gittings and Modified Lobster Traps, divers were required to set the subsurface floats manually. We did not determine a best strategy for deploying the traps with subsurface floats. Traps were weighted to facilitate their opening, ncreasing the weight of the traps would have likely adjusted for the subsurface floats but made them difficult to manage on the research boat.
Despite improvements to trap weight balance, floatation set up and deployment plans traps still failed to open often when hitting unevent rocky habitat or artificial structure instead of sand.
Video of a Successful Deployment
Field Testing Summary
After the trap design was completed the REEF Conservation Science team completed a rigorous set of field testing for two types of deep water traps to capture invasive lionfish: the Gittings Noncontainment Trap, and a modified lobster trap, both designed for capturing lionfish from mesophotic reefs in the Florida Keys. The modified lobster trap was designed based on the field testing of Florida Fish and Wildlife Commission research team.
With the help of Forever Young Charter Company and local volunteers, our team deployed these traps in a paired design at 43 different natural and artificial reefs across the Upper Florida Keys. The two trap types were each deployed for three days , in the sand near a reef or artificial structure, in 30 meters of water. To test if light lured in more lionfish or bycatch, nearly half of the traps also had pot lights on them. The goal was to understand lionfish and bycatch catch rate and recruitment for each trap design. At the end of the field testing period, one lionfish had been caught in the lobster trap, and zero lionfish were caught in the Gittings traps. Although both designs yielded minimal bycatch, the lobster trap produced slightly higher bycatch, with Tomtate grunts and Hogfish being the most commonly caught species.
After field testing was complete, the team spent several months reviewing video footage from the deployments (each trap was paired with a camera with intervalometer recording 30 seconds every hour. Video analysis suggests that there was limited recruitment of lionfish to both trap designs, even when lionfish were abundant on nearby sites. Based on the results of this study, it seems that traps may not be effective in attracting invasive lionfish and reducing populations, even on relatively low relief deep water reef sites.
REEF Conservation Science Associate Lex Bryant presented a research poster describing these results, titled “Testing the Efficacy of Lionfish Traps in the Florida Keys” at the 76th Annual Gulf and Caribbean Fisheries Institute (GCFI) Conference. She discussed the trap design and field tested deployment strategies as well as paired design with modified lobster traps completed during the duration of the project.
2023 Gulf and Caribbean Fisheries Institute Conference Poster
Modifications to Gittings Trap to improve deployment success and reduced fish escape rate
Final trap modifications and project results are summarized in the following video.
Trap Project Summary Video
Collaboration with Florida Keys Lobster Fishers and Gear Development Teams
Project staff worked with Florida Keys Lobster Fishers as well as NOAA Fisheries gear development experts to design the traps and test deployment strategies. Field testing on lobster boats with the Gittings traps did not result in any lionfish catch. Traps were deployed with lobster traps Gittings traps did not successfully deploy with placed in trawl line with other traps. The drag from the trawl lines likely prevented the traps from opening when they hit the bottom and they fell over closed.
Previous Trap Research
Gittings S.R. 2016. Encouraging Results in Tests of New Lionfish Trap Design. Proceedings of the 69th Annual Gulf and Caribbean Fisheries Institute. 69:206-214
Hutchinson E., Hagedorn S., Butler, J and Sweetman, C and Matthews, Development of a Trap to Catch the Invasive Lionfish (Pterois spp). Proceedings of the 72nd Gulf and Caribbean Fisheries Institute November 2 - 8, 2019 Punta Cana, Dominican Republic.
Harris HE, Garner, SB, Tarnecki JH, Gittings SR, Chagaris DD, et al. 2023. Three trap designs evaluated for a deepwater lionfish fishery. Frontiers in Marine Science, 14(4), 1-12. https://doi.org/10.3389/fmars.2023.1121642
Harris HE, Fogg AQ, Gittings SR, Ahrens RNM, Allen MS, et al. 2020 Testing the efficacy of lionfish traps in the northern Gulf of Mexico. PLOS ONE 15(8):e0230985. https://doi.org/10.1371/journal.pone.0230985
Bermuda Institute of Ocean Sciences Assessing the utility of lionfish traps for preserving biodiversity by managing invasive populations 2019 BEST 2.0.
AP - Testing traps to control lovely but destructive lionfish - August 2020
PBS Nova Oceans Invaders - October 2022
REEF would like to thank all of our partners for their contribution to the project including Forever Young Spearfishing Charters and Florida Fish and Wildlife Conservation Commision.