---
title: "Setting longlines deep and at night saves albatrosses in a Pacific tuna fishery"
---

# Setting longlines deep and at night saves albatrosses in a Pacific tuna fishery

*![Flavia Barreto Laysan Albatross flying water colour Kirk Zufelt](https://acap.aq/images/WAD2022/Flavia_Barreto_Laysan_Albatross_flying_water_colour_Kirk_Zufelt.jpg)At risk to longlines in the Pacific: a Laysan Albatross at sea, painted by Flávia Barreto, Artists and Biologists Unite for Nature for World Albatross Day 2022, after a photograph by Kirk Zufelt*

 Eric Gilman (Fisheries Research Group, [The Safina Center](https://www.safinacenter.org/), Honolulu, USA) and colleagues have published open access in the journal [*Scientific Reports*](https://www.nature.com/srep/)showing that setting baited fishing gear deeply and at night resulted in a 99% lower seabird catch rate (70% were albatrosses) than with lines set shallowly during the day in a in a temperate Pacific longline fishery targeting Albacore Tuna *Thunnus alalunga*.

 The paper’s abstract follows:

 “Marine megafauna exposed to fisheries bycatch belong to some of the most threatened taxonomic groups and include apex and mesopredators that contribute to ecosystem regulation. Fisheries bycatch is a major threat to the conservation of albatrosses, large petrels and other pelagic seabirds. Using data sourced from a fisheries electronic monitoring system, we assessed the effects of the time-of-day and relative depth of fishing on seabird and target species catch rates for a Pacific Ocean pelagic longline fishery that targets albacore tuna with an apparently high albatross bycatch rate. Using a Bayesian inference workflow with a spatially-explicit generalized additive mixed model for albacore tuna and generalized linear mixed regression models both for combined albatrosses and combined seabirds, we found that time-of-day and fishing depth did not significantly affect the target species catch rate while night-time deep setting had > 99% lower albatross and total seabird catch rates compared to both deep and shallow partial day-time sets. This provides the first evidence that night-time setting in combination with fishing deep reduces seabird catch risk and may be commercially viable in this and similar albacore tuna longline fisheries. Findings support evidence-informed interventions to reduce the mortality of threatened seabird bycatch species in pelagic longline fisheries.”

 Read a popular account of the publication [here](https://www.pewtrusts.org/en/research-and-analysis/articles/2023/05/10/with-small-changes-fishers-can-drastically-reduce-seabird-deaths?fbclid=IwAR2sFxA4-xEMa66NRS_S-hv9klxZpz-J-xkVp-SRgysQAI3u8dFylFTamQA).

 **Reference:**

 Gilman, E., Evans, T., Pollard, I*.*& Chaloupka, M. 2023. Adjusting time-of-day and depth of fishing provides an economically viable solution to seabird bycatch in an albacore tuna longline fishery. *[Scientific Reports](https://www.nature.com/articles/s41598-023-29616-7)*[13, 262. doi.org/10.1038/s41598-023-29616-7](https://www.nature.com/articles/s41598-023-29616-7).

 *17 May 2023*