Fig 1.
Schematic of Gittings lionfish trap deployment.
Traps are designed to A) descend closed and B) open when the curved deflectors contact the seafloor. C) The traps remain open during deployment then close when the trap is ascended during retrieval.
Table 1.
Goals of the Gittings lionfish trap with design attributes employed to achieve those goals.
Fig 2.
In water photos of a Gittings lionfish traps deployed near artificial reefs in the northern Gulf of Mexico.
Lionfish are attracted to the structure made from plastic lattice. The trap jaws are constructed from rebar and bent to make deflectors that open the trap when it contacts the seafloor. The jaws open around a central pivot axle connected with a hinge plate. Fish are captured in the mesh nylon netting when the jaws are lifted via a two-line harness. Images: A. Fogg and H. Harris.
Fig 3.
Study site locations for testing Gittings lionfish traps.
A) Traps were deployed adjacent to artificial reefs approximately 30 km offshore NW Florida in depths of 33–37 m. The eight reef study sites were B) separated by >300 m and C) located in the northern Gulf of Mexico.
Table 2.
Replicates by deployment factor tested.
Fig 4.
Number and species of fishes in the Gittings traps.
Total counts of lionfish caught, lionfish escaped, and native fish caught in traps deployed near northern Gulf of Mexico artificial reefs during 82 trap deployments. Sizes of pie slices correspond to the proportion of total fish caught. Fish images are not drawn to scale.
Fig 5.
Lionfish and native fish recruitment.
Mean (± 95 CI) count of lionfish and native fish observed within the trap footprint during retrieval, with the number of replicates per level indicated (n). Trap deployment configurations examined factors of A) distance to the adjacent artificial reef, B) number of traps, and C) soak time.
Table 3.
Generalized mixed model results testing deployment factors on lionfish and native fish species recruitment and catches by Gittings traps.
Fig 6.
Lionfish size distributions by distance to reef and harvest gear.
A) Lionfish total length (TL) probability density distributions for lionfish captured in Gittings traps deployed at 5 m and 15 m distances to the adjacent artificial reef. B) Lionfish TL distributions for lionfish harvested by Gittings traps (all treatments) and lionfish sampled concurrently (June–December 2018) by spearfishing on similar northern Gulf of Mexico artificial reefs. Mean TL per distribution is indicated by a vertical dashed line.