156 - Novel deep‐water spawning patterns of bonefsh (Albula vulpes), a shallow water fish

Title:

Novel deep‐water spawning patterns of bonefsh (Albula vulpes), a shallow-water fish

Authors:

Steven M. Lombardo · Aaron J. Adams · Andy J. Danylchuk

· Cameron A. Luck · Matthew J. Ajemian

Abstract:

Coastal marine fshes that form spawning aggregations most commonly exhibit a two-point movement pattern, with locations separated by migration: home range to spawning aggregation site and return to home range. However, the bonefsh, Albula vulpes, partakes in a unique three-point spawning migration. Bonefsh migrate up to 80 km from shallow water home fats to form nearshore pre-spawning aggregations (PSA) before moving ofshore to spawn. Although these broad patterns have previously been documented, details of the ofshore spawning-associated diving behavior have yet to be rigorously examined. Using active acoustic telemetry and sonar data in 2019 in Abaco, The Bahamas, we provide a complete account of bonefsh ofshore spawning movements and novel deep diving behavior to 137.9 m. Bonefsh were continuously observed at depths≥100 m for 2 h; a time period that included multiple depth changes and culminated in a spawning ascent to 67.3 m at 0.57 m s−1. These new data on bonefsh ofshore movements and deep dives, coupled with CTD data, suggest that bonefsh actively spawn at pycnoclines and thermoclines. Two previous tracking attempts (2013, 2018) at this location refect spatiotemporal plasticity in spawning, a behavior counter to other aggregation forming fshes. This is the frst detailed documentation of such deep spawning for a shallow water coastal fsh species. The ecological motivation for diving to the deepest depths remains speculative. Future work must examine the dynamic relationship between bonefsh diving behavior, spawning site selection, and oceanographic features.

158 - Hook disgorgers remove deep hooks but kill fish: A plea for cutting the line

Title:

Hook disgorgers remove deep hooks but kill fish: A plea for cutting the line

Authors:

Steven J. Cooke and Andy J. Danylchuk

Abstract:

Recreational fishing can result in deep hooking (e.g. in the gullet) of fish that are

intended to be released, leading to the development of various tools intended to as-

sist with hook removal. So-called “hook disgorgers” are typically marketed as being

a mechanism to retrieve the hook while doing so in a way that reduces harm to the

fish, despite there being many studies that demonstrate that it is best to cut the line

for deeply hooked fish. A study was designed to test the effectiveness of six different

hook disgorgers for deeply hooked smallmouth bass, Micropterus dolomieu Lacépède,

captured using baitholder hooks relative to shallow hooked controls and fish for

which the line was cut. Reflex impairment and survival at 10 min, 1 hr and 24 hr were

assessed. The study was terminated after early results revealed that all but one of

the fish that had the hook removed died (n = 17), while all fish that were hooked in

the jaw (n = 4) or had the line cut (n = 5) survived. The ethical conundrum faced by

the research team is discussed here, recognising that an incomplete study would have

less statistical rigour even though it was very clear that disgorgers used when hooks

were in the gullet killed the fish. Stopping rules are common in pharmaceutical trials

and can also be used to inform catch-and-release research to maintain fish welfare.

Best practices for anglers include cutting the line when fish are hooked in the gullet,

and changing fishing strategies and gear type when deep hooking is encountered on

a routine basis, otherwise mortality can be unnecessarily high.

157 - Fisheries science and marine education catalyze the renaissance of traditional management (rahui) to improve an artisanal fishery in French Polynesia

Title:

Fisheries science and marine education catalyze the renaissance of traditional management (rahui) to improve an artisanal fishery in French Polynesia

Authors:

Alexander Filous, Robert J. Lennox, Jean Pierre Beaury, Hinano Bagnis, Mathew Mchugh, Alan M. Friedlander, Eric E.G. Clua, Steven J. Cooke, Todd K. Fuller, Andy J. Danylchuk

Abstract:

.Coral reef fisheries provide important ecosystem services to coastal communities, yet in the Pacific Islands, many of these contemporary fisheries are threatened by overexploitation. Historically, Pacific Island societies successfully utilized community-based management and spatial temporal closures to regulate the harvest of marine resources. In recognition of their past success these actions are currently being reemployed throughout the region. However, in many communities, innovative approaches may be needed to revitalize such practices and adapt traditional management to contemporary societal needs and expectations. This study presents the case of Anaa Atoll, a remote Pacific Island in the Tuamotu Archipelago of French Polynesia, and the community’s efforts to conserve a culturally important but overexploited bonefish (Albula glossodonta) fishery. Ultimately, fisheries research, education, and the creation of Aire Marine Educative (a marine area that is managed by a local primary school) were successful in building social cohesion and supporting the renaissance of rahui (a traditional form of restricting access to resources and or territories) to manage this fishery. On March 1st, 2019, the community of Anaa reinitiated this tradition for the first time in centuries. Based on these experiences, and an ensuing increase in the Spawning Potential Ratio of the bonefish stock, it is proposed that nationally recognized local management systems that incorporate fisheries research, youth education, and the cultural practices of communities should be supported in the marine policies of the Pacific Islands and beyond.