A multi-faceted approach for quantifying the estuarine-nearshore transition in the life cycle of the bull shark, Carcharhinus leucas.


Autoria(s): Werry, J.M.; Lee, S.Y.; Otway, N.M.; Hu, Y.; Sumpton, W.
Data(s)

2012

Resumo

Understanding the ontogenetic habitat linkages of sharks is important for conservation and managing human interactions. We used acoustic telemetry, catch data, elemental and stable isotope signatures and dietary analyses to investigate ontogenetic habitat use in south-east Queensland, Australia, by the bull shark Carcharhinus leucas, a IUCN 'near-threatened' species that is implicated in many shark attacks on humans in urban estuaries. Sequential analyses for delta(15)N and delta(13)C of vertebrae from five adult C. leucas and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) for elemental composition from 23 C. leucas, including a pregnant female, were also used to trace ontogenetic habitat dependence. Acoustic telemetry indicated large juvenile and subadult C. leucas remained in estuarine habitats. delta(15)N values across shark vertebrae showed an ontogenetic shift in diet with total length (TL), confirmed by stomach contents. LA-ICPMS data reflected the ontogenetic movements of C. leucas from natal habitats. Differences among adults were gender related. Shifts in habitat use by subadults were correlated with a sigmoidal delta(13)C relationship with TL. C. leucas have a multipartite, stage-specific dependency in their transition between habitats along the freshwater-estuarine-marine continuum, making them particularly susceptible to the habitat alteration that is occurring globally.

Identificador

Werry, J.M. and Lee, S.Y. and Otway, N.M. and Hu, Y. and Sumpton, W. (2012) A multi-faceted approach for quantifying the estuarine-nearshore transition in the life cycle of the bull shark, Carcharhinus leucas. Marine and Freshwater Research, 62 (12). pp. 1421-1431.

http://era.daf.qld.gov.au/3118/

Publicador

CSIRO Publishing

Relação

http://dx.doi.org/10.1071/MF11136

http://era.daf.qld.gov.au/3118/

Palavras-Chave #Fishes #Fishery conservation
Tipo

Article

PeerReviewed