DATASET

Foraging habitat of blue shark (Prionace glauca) - Global Ocean MONTHLY - 2003-2018 (% of daily favorable occurrence, 1/24° by 1/24°)

Collection: GMIS : Global Marine Information System 

Description

Blue shark (Prionace glauca) is amongst the most abundant shark species in international trade, however this highly migratory species has little effective management and the need for spatio-temporal strategies increases, possibly involving the most vulnerable stage or sex classes. We combined 265,595 blue shark observations (capture or satellite tag) with environmental data to present the first global-scale analysis of species’ habitat preferences for five size and sex classes (small juveniles, large juvenile males and females, adult males and females). We leveraged the understanding of blue shark biotic environmental associations to develop two indicators of foraging location: productivity fronts in mesotrophic areas and mesopelagic micronekton in oligotrophic environments. Temperature (at surface and mixed layer depth plus 100 m) and sea surface height anomaly were used to exclude unsuitable abiotic environments. To capture the horizontal and vertical extent of thermal habitat for the blue shark, we defined the temperature niche relative to both sea surface temperature (SST) and the temperature 100 m below the mixed layer depth (Tmld+100). We show that the lifetime foraging niche incorporates highly diverse biotic and abiotic conditions: the blue shark tends to shift from mesotrophic and temperate surface waters during juvenile stages to more oligotrophic and warm surface waters for adults. However, low productivity limits all classes of blue shark habitat in the tropical western North Atlantic, and both low productivity and warm temperatures limit habitat in most of the equatorial Indian Ocean (except for the adult males) and tropical eastern Pacific. Large females tend to have greater habitat overlap with small juveniles than large males, more defined by temperature than productivity preferences. In particular, large juvenile females tend to extend their range into higher latitudes than large males, likely due to greater tolerance to relatively cold waters. Large juvenile and adult females also seem to avoid areas with intermediate SST (~21.7-24.0°C), resulting in separation from large males mostly in the tropical and temperate latitudes in the cold and warm seasons, respectively.

The habitat requirements of sensitive size- and sex-specific stages to blue shark population dynamics are essential in management to improve conservation of this near-threatened species. More information: https://fishreg.jrc.ec.europa.eu/fish-habitat

Contact

Email
jean-noel.druon (at) ec.europa.eu

Contributors

How to cite

European Commission, Joint Research Centre (JRC) (2022): Foraging habitat of blue shark (Prionace glauca) - Global Ocean MONTHLY - 2003-2018 (% of daily favorable occurrence, 1/24° by 1/24°) . European Commission, Joint Research Centre (JRC) [Dataset] PID: http://data.europa.eu/89h/6062ddae-2478-409a-89bf-8121902dc70e

Keywords

Environmental monitoring Feeding Habitat Fishing mitigation Fisheries Overfishing Pelagic fishing gears Ocean colour Satellite observations Prionace glauca Top predator GIS digital format

Data access

Foraging habitat of blue shark (Prionace glauca) - ADULT MALES - Global Ocean MONTHLY - 2003-2018
URL 
Foraging habitat of blue shark (Prionace glauca) - LARGE JUVENILE MALES - Global Ocean MONTHLY - 2003-2018
URL 
Foraging habitat of blue shark (Prionace glauca) - SMALL JUVENILES - Global Ocean MONTHLY - 2003-2018
URL 
Foraging habitat of blue shark (Prionace glauca) - LARGE JUVENILE FEMALES - Global Ocean MONTHLY - 2003-2018
URL 
Foraging habitat of blue shark (Prionace glauca) - ADULT FEMALES - Global Ocean MONTHLY - 2003-2018
URL 
Global-scale environmental niche and habitat of blue shark (Prionace glauca) by size and sex: a pivotal step to improving stock management
URL 
  • Blue shark (Prionace glauca) is amongst the most abundant shark species in international trade, however, this highly migratory species has little effective management and the need for spatio-temporal strategies increases, possibly involving the most vulnerable stage or sex classes. We combined 265,595 blue shark observations (capture or satellite tag) with environmental data to present the first global-scale analysis of species’ habitat preferences for five size and sex classes (small juveniles, large juvenile males and females, adult males and females). We leveraged the understanding of blue shark biotic environmental associations to develop two indicators of foraging location: productivity fronts in mesotrophic areas and mesopelagic micronekton in oligotrophic environments. Temperature (at surface and mixed layer depth plus 100 m) and sea surface height anomaly were used to exclude unsuitable abiotic environments. To capture the horizontal and vertical extent of the thermal habitat for the blue shark, we defined the temperature niche relative to both sea surface temperature (SST) and the temperature 100 m below the mixed layer depth (Tmld+100). We show that the lifetime foraging niche incorporates highly diverse biotic and abiotic conditions: the blue shark tends to shift from mesotrophic and temperate surface waters during juvenile stages to more oligotrophic and warm surface waters for adults. However, low productivity limits all classes of blue shark habitat in the tropical western North Atlantic, and both low productivity and warm temperatures limit habitat in most of the equatorial Indian Ocean (except for the adult males) and tropical eastern Pacific. Large females tend to have greater habitat overlap with small juveniles than large males, more defined by temperature than productivity preferences. In particular, large juvenile females tend to extend their range into higher latitudes than large males, likely due to greater tolerance to relatively cold waters. Large juvenile and adult females also seem to avoid areas with intermediate SST (~21.7-24.0°C), resulting in separation from large males mostly in the tropical and temperate latitudes in the cold and warm seasons, respectively.

    The habitat requirements of sensitive size- and sex-specific stages to blue shark population dynamics are essential in management to improve the conservation of this near-threatened species. More information: https://fishreg.jrc.ec.europa.eu/fish-habitat

Publications

Publication
Global-scale environmental niche and habitat of blue shark (Prionace glauca) by size and sex: a pivotal step to improving stock management
Druon, J., Campana, S., Vandeperre, F., Hazin, F., Bowlby, H., Coelho, R., Queiroz, N., Serena, F., Abascal, F., Damalas, D., Musyl, M., Lopez, J., Block, B., Afonso, P., Dewar, H., Sabarros, P., Finucci, B., Zanzi, A., Bach, P., Senina, I., Garibaldi, F., Sims, D., Navarro, J., Cermeño, P., Leone, A., Diez, G., Carreón Zapiain, M.T., Deflorio, M., Romanov, E.V., Jung, A., Lapinski, M., Francis, M.P., Hazin, H. and Travassos, P., Global-scale environmental niche and habitat of blue shark (Prionace glauca) by size and sex: a pivotal step to improving stock management, FRONTIERS IN MARINE SCIENCE, ISSN 2296-7745 (online), 9, 2022, p. 828412, JRC126294.
  • FRONTIERS MEDIA SA, LAUSANNE, SWITZERLAND
  • Abstract

    Blue shark (Prionace glauca) is amongst the most abundant shark species in international trade, however this highly migratory species has little effective management. We combined 265,595 blue shark observations (capture or satellite tag) with environmental data to present the first global-scale analysis of species’

    habitat preferences by size and sex classes (small juveniles, large juvenile males and females, adult males and females). We show that the lifetime foraging niche incorporates highly diverse biotic and abiotic conditions: the blue shark tends to shift from mesotrophic and temperate surface waters during juvenile stages to more oligotrophic and warm surface waters for adults. Large females tend to have greater habitat overlap with small juveniles than large males, more defined by temperature than productivity preferences. In particular, large juvenile females tend to extend their range into higher latitudes than large males, likely due to greater tolerance to relatively cold waters. Large females (FL above 125cm) also seem to avoid areas with intermediate SST (~21.7-24.0°C), resulting in separation from large males mostly in the tropical and temperate latitudes in the cold and warm seasons, respectively. Current management tends to ignore stage- and sex-specific habitat requirements of blue sharks, thus confounding attempts to improve management and conservation of this near-threatened species.

Geographic areas

World

Spatial coverage

Type Value
WKT
POLYGON((180 90,-180 90,-180 -90,180 -90,180 90))

Temporal coverage

From date To date
2003-01-01 2018-12-31

Additional information

Published by
European Commission, Joint Research Centre
Created date
2022-04-04
Modified date
2022-04-20
Issued date
2022-04-06
Landing page
https://joint-research-centre.ec.europa.eu/scientific-tools-and-databases/global-marine-information-system-gmis_en 
Language(s)
English
Data theme(s)
Agriculture, fisheries, forestry and food
Update frequency
annual
Identifier
http://data.europa.eu/89h/6062ddae-2478-409a-89bf-8121902dc70e
Popularity