Assessing the Relative Selectivity of Multiple Sampling Gears for Managed Reef Fishes in the Eastern Gulf of Mexico

Abstract

Fishery-independent data are important for the effective management of reef fishes in the eastern Gulf of Mexico. Proper characterization of selectivity, or the effectiveness of each type of sampling gear in capturing a species or a size-class, is essential to ensure that assessment models treat various sources of data appropriately. In this study, we analyzed fishery-independent data that was collected using stereo-baited remote underwater video (S-BRUV) arrays, chevron traps (TRAP), and two types of hooked gear (repetitive timed-drop [RTD] and vertical longline [VLL]) to assess gear-related differences of species composition and size selectivity of managed reef fishes in the eastern Gulf of Mexico. Significant differences were detected in the assemblage structures of reef fishes in relation to region, gear type, and depth. Overall, eight managed species were identified as contributing to the top 70% of the assemblage structure for each gear type. Stereo-baited remote underwater video had the highest abundances for most of the species and the highest number of species captured, while VLL had the lowest. Two economically and ecologically important species (Red Grouper Epinephelus morio and Red Snapper Lutjanus campechanus) were common to all four gear types, and the size selectivity of these two species generally overlapped. However, significant differences among gear types were detected. Unimodal selection curves for hooked gears indicated that size of Red Snapper and Red Grouper increased as hook size increased. These data provide insight on species and size selectivity of multiple gears, which will contribute to future survey design and aid in the management of reef-fish populations.

A Habitat‐Based, Fishery‐Independent Survey Using Actively Fished Hooked Gear Successfully Characterizes Reef Fish Populations in the Eastern Gulf of Mexico

“…2012; Christiansen et al. 2020). We found that modal size of caught fish increased with hook size as was found in other hooked‐gear reef fish studies (Ralston 1990; Otway and Craig 1993; Erzini et al.…”

“…Sample collection.-All sampling was conducted using the repetitive timed-drop (RTD) method, a standardized, active hook-and-line fishing technique developed in collaboration with industry partners (Guenther et al 2013(Guenther et al , 2014Stallings et al 2014;Christiansen et al 2020). Each angler used a rod-and-reel rig consisting of an electric reel drive (12 V DC, Elec-tra-mate model 620D or 940XP), a fishing reel (Diawa Sealine 600H 6/0 or Penn Senator 115 L 9/0) containing Ande 45.4-kg-test monofilament, and a heavyduty fiberglass fishing pole (2.1-2.4 m long).…”

“…In the present study we used multiple hook sizes, which minimized hook selectivity bias and allowed for the capture of a broad size range of fishes because fish size increases with increasing hook size (Chester et al 1984;Ralston 1990;Murphy and Jenkins 2010;Gregalis et al 2012;Hayes et al 2012;Hubert et al 2012;Christiansen et al 2020). We found that modal size of caught fish increased with hook size as was found in other hooked-gear reef fish studies (Ralston 1990;Otway and Craig 1993;Erzini et al 1998;Gregalis et al 2012;Garner and Patterson 2015;Christiansen et al 2020). Like Garner et al (2017), we found that hook size significantly affected estimates of reef fish abundance and community structure.…”

Composición de los desembarques de la pesca artesanal en los puertos de Boca Parita y El Agallito, Pacífico panameño

“…La longitud de captura está directamente relacionada a la que alcanza el pez, la zona y profundidad de la pesca y el arte utilizado, que define una selectividad (Christiansen et al 2020). De las 13 especies a las cuales se le analizó la estructura de tallas, solo para siete se encontró información publicada sobre media reproductiva (L 50 ).…”

Conservation implications of white shark (Carcharodon carcharias) behaviour at the northern extent of their range in the Northwest Atlantic

“…Tagging onboard following capture is known to alter movement behaviour during a prolonged recovery period for lamnid sharks (Hoolihan et al 2011;Bowlby et al 2021) and carcharhinid species (Vaudo et al 2014). Also, our non-capture tagging methodology was unaffected by gear selectivity, unlike capture-based sampling that is known to be size-selective (Maunder et al 2006;Rotherham et al 2007;Christiansen et al 2020).…”