Abundance and demography of a seasonal aggregation of zebra sharks Stegostoma fasciatum
2008; Inter-Research; Volume: 368; Linguagem: Inglês
10.3354/meps07581
ISSN1616-1599
AutoresChristine L. Dudgeon, Michael J. Noad, Janet M. Lanyon,
Tópico(s)Fish Biology and Ecology Studies
ResumoMEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 368:269-281 (2008) - DOI: https://doi.org/10.3354/meps07581 Abundance and demography of a seasonal aggregation of zebra sharks Stegostoma fasciatum Christine L. Dudgeon1,*, Michael J. Noad2, Janet M. Lanyon1 1School of Integrative Biology, and 2School of Veterinary Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia *Email: c.dudgeon@uq.edu.au ABSTRACT: Seasonal aggregations commonly occur in the marine environment where typically wide-ranging organisms come together to exploit temporary resources or find conspecifics for mating events. The zebra shark Stegostoma fasciatum is a demersal carpet shark that aggregates over the austral summer months in the coastal waters of southeast Queensland, Australia. This study employed photo-identification and mark-recapture methods over a 3 yr period (2003 to 2006) to investigate the population size and structure of this aggregation. In total 327 individual zebra sharks were identified from 570 photographs. Numbered dart-tags on 15 zebra sharks were used to confirm that pigmentation patterns were unique and persistent in wild zebra sharks for up to 810 d. Pollock’s robust design resulted in an annual population estimate of 458 individuals (95% CI = 298–618). The mean number of zebra sharks observed on a single day was 8 (± 8 SE) and the maximum number of zebra sharks seen on a single day was 34. In total, 27% of the sharks were sighted in more than one summer aggregation period and males had greater re-capture probabilities than females. The aggregation consisted exclusively of large (>1800 mm total length) adults with an overall female sex bias of 3.8:1 though sex-ratios varied temporally. Predictable visitation of large, presumably mature individuals to the site raises conservation concerns if aggregations of similar size and structure occur in regions where zebra sharks are fished. KEY WORDS: Mark-recapture · Seasonal aggregation · Zebra shark · Stegostoma fasciatum · Photo-identification · Abundance Full text in pdf format PreviousNextCite this article as: Dudgeon CL, Noad MJ, Lanyon JM (2008) Abundance and demography of a seasonal aggregation of zebra sharks Stegostoma fasciatum. Mar Ecol Prog Ser 368:269-281. https://doi.org/10.3354/meps07581 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 368. Online publication date: September 25, 2008 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2008 Inter-Research.
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