Performance of a low-cost, solar-powered pop-up satellite archival tag for assessing post-release mortality of Atlantic bluefin tuna (Thunnus thynnus) caught in the US east coast light-tackle recreational fishery

Abstract

Background: Pop-up satellite archival tags (PSATs) are a valuable tool for estimating mortality of pelagic fishes released from commercial and recreational fishing gears. However, the high cost of PSATs limits sample sizes, resulting in low-precision post-release mortality estimates with little management applicability. We evaluate the performance of a lower-cost PSAT designed to enable large-scale post-release mortality studies. The tag uses solar rather than battery power, does not include a depth sensor, and transmits daily summaries of light and temperature data rather than high-resolution habitat profiles, contributing to a substantially lower per-unit price. We assessed the tag's ability to detect mortality while also estimating the post-release mortality of juvenile (119-< 185 cm) Atlantic bluefin tuna (Thunnus thynnus) caught using light-tackle angling methods along the US east coast. Results: Using high-resolution data from previously deployed PSATs and environmental information from the general tagging location, we established parameters to infer mortality for Atlantic bluefin tuna using only daily summary data. We then deployed 22 PSATs, programmed to pop off after 31 days (thus providing 30 full daily summaries), on Atlantic bluefin tuna caught using light tackle off the coasts of Massachusetts and North Carolina, USA, in 2015 and 2016. Data were recovered for 15 tags with deployments ranging from 7 days (premature shedding) to 95 days (failed pop-off) and indicated that tagged fish spent sufficient time near the surface to keep the solar-powered tags fully charged. Fourteen fish demonstrated strong temporal changes in temperature indicating vertical movement in the water column, consistent with survival. One fish was predated upon after 17 days, likely by a shortfin mako, and was considered a natural mortality, resulting in a post-release mortality estimate of 0%. Conclusions: While low reporting rates complicated inferences about post-release mortality, the concept of using species-specific mortality parameters coupled with a reduced dataset shows promise as a cost-effective tool for detecting post-release mortality using PSATs. In addition, findings suggest that catch-and-release angling is a viable conservation strategy for juvenile Atlantic bluefin tuna caught in the US east coast light-tackle fishery.

Movement and thermal niche of the first satellite‐tagged Mediterranean spearfish (Tetrapturus belone)

“…() suggests that new tag attachment methods and/or tag anchors, which minimize injury and potential behavioral effects, may need to be developed for the small‐bodied, laterally compressed spearfishes. In contrast, three studies with successful PSAT data reports from a combined 57 juvenile Atlantic bluefin tuna ( Thunnus thynnus ), which are small in size but have a robust body morphology, documented no tag‐associated post release mortality and only two inferred natural predation events (Galuardi & Lutcavage, ; Goldsmith, Scheld, & Graves, ; Marcek, Fabrizio, & Graves, ). Future work on the Mediterranean spearfish should assess long‐term movement patterns for a large number of individuals, identify additional spawning areas, and determine the species’ population structure.…”

“…Although the Mediterranean spearfish is a target of secondary importance in the traditional Italian harpoon fishery (Romeo et al, 2015) and rare bycatch in other commercial fisheries ( morphology, documented no tag-associated post release mortality and only two inferred natural predation events (Galuardi & Lutcavage, 2012;Goldsmith, Scheld, & Graves, 2017;Marcek, Fabrizio, & Graves, 2016). Future work on the Mediterranean spearfish should assess long-term movement patterns for a large number of individuals, identify additional spawning areas, and determine the species' population structure.…”

Characterizing the Preferences and Values of U.S. Recreational Atlantic Bluefin Tuna Anglers

“…; Marcek and Graves ; Goldsmith et al. ), suggesting that catch‐and‐release angling is a viable conservation strategy that would provide substantial benefits, especially to high‐income anglers.…”

“…However, the additional value attached by class 1 anglers to nonconsumptive aspects of Bluefin Tuna fishing (catch and release, hooking and losing fish, and other factors captured by the ASC) appear to provide sufficient incentive for this group to continue targeting Bluefin Tuna despite restrictive harvest regulations. Studies using pop-up satellite archival tags have indicated that postrelease mortality of Bluefin Tuna released in recreational fisheries is low (<5%) across size-classes (Stokesbury et al 2011;Marcek and Graves 2014;Goldsmith et al 2017), suggesting that catch-and-release angling is a viable conservation strategy that would provide substantial benefits, especially to high-income anglers.…”

Experimentally optimized and field validated three-dimensional electromagnetic energy harvester for smart farming applications

“…The number of papers researching energy harvesting from the non-human animal body is limited. Solar harvesting research was performed on zebras [21], north elephant seals [22], tuna [23], pink iguanas [24], turtles [25], and cattle [26]. Some limited research with thermoelectric energy harvesting of sheep has been performed [27].…”