Habitat use and movement patterns of tiger sharks (Galeocerdo cuvier) in eastern Australian waters

Abstract Understanding the movement of marine predators is vital for effective conservation and management. Despite being targeted by shark control programs, the tiger shark, Galeocerdo cuvier, is poorly studied off eastern Australia. To investigate the horizontal movement and habitat use in this region, 16 sharks (157–384 cm total length) were tagged with MiniPAT pop-up satellite archival tags in 2018 and 2019. Eleven of these individuals were also fitted with satellite-linked radio transmitting tags. After release, most sharks moved off the continental shelf and headed north, associating with seamounts as they moved towards Queensland. During their time at liberty they transited through temperate, sub-tropical and tropical waters and spent the majority of time in the upper 50 m of the water column and at temperatures between 22 and 25˚C. Horizontal movement was focused in waters off the continental shelf. Increased movement over shelf waters occurred during the austral spring and summer when the East Australian Current is at its strongest and warm waters encroach the continental shelf. Broad latitudinal movement along the east coast of Australia was evident and highlights the connectivity between tropical and warm-temperate regions.

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Retrospective Genomics Suggests the Disappearance of a Tiger Shark (Galeocerdo Cuvier) Population Off South-Eastern Australia

10.21203/rs.3.rs-334053/v1 ◽

2021 ◽

Author(s):

Alice Manuzzi ◽

Belen Jiménez-Mena ◽

Romina Henriques ◽

Bonnie J. Holmes ◽

Julian Pepperell ◽

...

Keyword(s):

Anthropogenic Disturbance ◽

East Coast ◽

Tiger Shark ◽

Galeocerdo Cuvier ◽

Relative Contribution ◽

Eastern Australia ◽

Genomic Analyses ◽

Dramatic Shift ◽

Well Differentiated ◽

Two Populations

Abstract Over the last century, many populations of sharks have been reduced in numbers by overexploitation or attempts to mitigate human-shark interactions. Still, there is a general perception that populations of large ocean predators cover wide areas and therefore their diversity is less susceptible to local anthropogenic disturbance. Here we report retrospective genomic analyses of DNA using archived and contemporary samples of tiger shark (Galeocerdo cuvier) from eastern Australia. Using SNP loci, we documented a significant overall change in genetic composition of tiger sharks born over the last century. The change was most likely due to a shift over time in the relative contribution of two well differentiated, but hitherto cryptic populations. Our data strongly indicate a dramatic shift in relative contribution of the two populations to the overall tiger shark abundance of the east coast of Australia, possibly associated with differences in direct or indirect exploitation rates.

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Tiger shark (Galeocerdo cuvier) movement patterns and habitat use determined by satellite tagging in eastern Australian waters

Marine Biology ◽

10.1007/s00227-014-2536-1 ◽

2014 ◽

Vol 161 (11) ◽

pp. 2645-2658 ◽

Cited By ~ 37

Author(s):

Bonnie J. Holmes ◽

Julian G. Pepperell ◽

Shane P. Griffiths ◽

Fabrice R. A. Jaine ◽

Ian R. Tibbetts ◽

...

Keyword(s):

Habitat Use ◽

Movement Patterns ◽

Tiger Shark ◽

Galeocerdo Cuvier ◽

Satellite Tagging

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Diel habitat use patterns of a marine apex predator (tiger shark, Galeocerdo cuvier) at a high use area exposed to dive tourism

Journal of Experimental Marine Biology and Ecology ◽

10.1016/j.jembe.2017.05.010 ◽

2017 ◽

Vol 495 ◽

pp. 24-34 ◽

Cited By ~ 10

Author(s):

N. Hammerschlag ◽

L.F.G. Gutowsky ◽

A.J. Gallagher ◽

P. Matich ◽

S.J. Cooke

Keyword(s):

Habitat Use ◽

Tiger Shark ◽

Apex Predator ◽

Use Patterns ◽

Galeocerdo Cuvier ◽

Dive Tourism ◽

Diel Habitat Use

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Influence of environmental variation on spatial distribution and habitat-use in a benthic foraging marine predator

Royal Society Open Science ◽

10.1098/rsos.211052 ◽

2021 ◽

Vol 8 (10) ◽

Author(s):

Cassie N. Speakman ◽

Andrew J. Hoskins ◽

Mark A. Hindell ◽

Daniel P. Costa ◽

Jason R. Hartog ◽

...

Keyword(s):

Spatial Distribution ◽

Habitat Use ◽

Large Scale ◽

Environmental Variability ◽

Southern Oscillation ◽

Environmental Variation ◽

Climate Indices ◽

Marine Systems ◽

Marine Predators ◽

Eastern Australia

The highly dynamic nature of the marine environment can have a substantial influence on the foraging behaviour and spatial distribution of marine predators, particularly in pelagic marine systems. However, knowledge of the susceptibility of benthic marine predators to environmental variability is limited. This study investigated the influence of local-scale environmental conditions and large-scale climate indices on the spatial distribution and habitat use in the benthic foraging Australian fur seal ( Arctocephalus pusillus doriferus ; AUFS). Female AUFS provisioning pups were instrumented with GPS or ARGOS platform terminal transmitter tags during the austral winters of 2001–2019 at Kanowna Island, south-eastern Australia. Individuals were most susceptible to changes in the Southern Oscillation Index that measures the strength of the El Niño Southern Oscillation, with larger foraging ranges, greater distances travelled and more dispersed movement associated with 1-yr lagged La Niña-like conditions. Additionally, the total distance travelled was negatively correlated with the current year sea surface temperature and 1-yr lagged Indian Ocean Dipole, and positively correlated with 1-yr lagged chlorophyll- a concentration. These results suggest that environmental variation may influence the spatial distribution and availability of prey, even within benthic marine systems.

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Regional variation in tiger shark (Galeocerdo cuvier) abundance and habitat use

10.25148/etd.fi10081208 ◽

2010 ◽

Author(s):

Kathryn Cameron

Keyword(s):

Habitat Use ◽

Regional Variation ◽

Tiger Shark ◽

Galeocerdo Cuvier

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Regional movements of the tiger shark, Galeocerdo cuvier, off northeastern Brazil: inferences regarding shark attack hazard

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652013005000055 ◽

2013 ◽

Vol 85 (3) ◽

pp. 1053-1062 ◽

Cited By ~ 17

Author(s):

FABIO H.V. HAZIN ◽

ANDRE S. AFONSO ◽

PEDRO C. DE CASTILHO ◽

LUCIANA C. FERREIRA ◽

BRUNO C.L.M. ROCHA

Keyword(s):

Attack Rate ◽

Movement Pattern ◽

Northeastern Brazil ◽

Tiger Shark ◽

The South ◽

Galeocerdo Cuvier ◽

Depth Data ◽

New Information ◽

Archival Tags ◽

Littoral Area

An abnormally high shark attack rate verified off Recife could be related to migratory behavior of tiger sharks. This situation started after the construction of the Suape port to the south of Recife. A previous study suggested that attacking sharks could be following northward currents and that they were being attracted shoreward by approaching vessels. In this scenario, such northward movement pattern could imply a higher probability of sharks accessing the littoral area of Recife after leaving Suape. Pop-up satellite archival tags were deployed on five tiger sharks caught off Recife to assess their movement patterns off northeastern Brazil. All tags transmitted from northward latitudes after 7-74 days of freedom. The shorter, soak distance between deployment and pop-up locations ranged between 33-209 km and implied minimum average speeds of 0.02-0.98 km.h−1. Both pop-up locations and depth data suggest that tiger shark movements were conducted mostly over the continental shelf. The smaller sharks moved to deeper waters within 24 hours after releasing, but they assumed a shallower (< 50 m) vertical distribution for most of the monitoring period. While presenting the first data on tiger shark movements in the South Atlantic, this study also adds new information for the reasoning of the high shark attack rate verified in this region.

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