Ocean-wide tracking of pelagic sharks reveals extent of overlap with longline fishing hotspots

Nuno Queiroz, Nicolas E. Humphries, Gonzalo Mucientes, Neil Hammerschlag, Fernando P. Lima, Kylie L. Scales, Peter I. Miller, Lara L. Sousa, Rui Seabra, David W. Sims

Research output: Contribution to journalArticle

80 Scopus citations

Abstract

Overfishing is arguably the greatest ecological threat facing the oceans, yet catches of many highly migratory fishes including oceanic sharks remain largely unregulated with poor monitoring and data reporting. Oceanic shark conservation is hampered by basic knowledge gaps about where sharks aggregate across population ranges and precisely where they overlap with fishers. Using satellite tracking data from six shark species across the North Atlantic, we show that pelagic sharks occupy predictable habitat hotspots of high space use. Movement modeling showed sharks preferred habitats characterized by strong sea surface-temperature gradients (fronts) over other available habitats. However, simultaneous Global Positioning System (GPS) tracking of the entire Spanish and Portuguese longline-vessel fishing fleets show an 80% overlap of fished areas with hotspots, potentially increasing shark susceptibility to fishing exploitation. Regions of high overlap between oceanic tagged sharks and longliners included the North Atlantic Current/Labrador Current convergence zone and the Mid-Atlantic Ridge southwest of the Azores. In these main regions, and subareas within them, shark/vessel co-occurrence was spatially and temporally persistent between years, highlighting how broadly the fishing exploitation efficiently "tracks" oceanic sharks within their space-use hotspots year-round. Given this intense focus of longliners on shark hotspots, our study argues the need for international catch limits for pelagic sharks and identifies a future role of combining fine-scale fish and vessel telemetry to inform the ocean-scale management of fisheries.

Original languageEnglish (US)
Pages (from-to)1582-1587
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume113
Issue number6
DOIs
StatePublished - Feb 9 2016

Keywords

  • Animal telemetry
  • Conservation
  • Distribution
  • Fisheries
  • Predator-prey

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Ocean-wide tracking of pelagic sharks reveals extent of overlap with longline fishing hotspots'. Together they form a unique fingerprint.

  • Cite this

    Queiroz, N., Humphries, N. E., Mucientes, G., Hammerschlag, N., Lima, F. P., Scales, K. L., Miller, P. I., Sousa, L. L., Seabra, R., & Sims, D. W. (2016). Ocean-wide tracking of pelagic sharks reveals extent of overlap with longline fishing hotspots. Proceedings of the National Academy of Sciences of the United States of America, 113(6), 1582-1587. https://doi.org/10.1073/pnas.1510090113