Extinction risk and conservation of the world’s sharks and rays
Overall chondrichthyan extinction risk is substantially higher for sharks, rays, and chimaeras than for most other vertebrates, and only one-third of species are considered safe.
Shark nursery areas: concepts, definition, characterization and assumptions
- M. Heupel, J. Carlson, C. Simpfendorfer
- Environmental Science
- 14 May 2007
A new more quantitative definition of shark nursery areas is proposed that requires 3 criteria to be met for an area to be identified as a nursery: sharks are more commonly encountered in the area than other areas; sharks have a tendency to remain or return for extended periods; and the area or habitat is repeatedly used across years.
A review of detection range testing in aquatic passive acoustic telemetry studies
This study presents a comprehensive review of how acoustic detection range has been considered and assessed to date, summarizes important variables to monitor when determining the detection range of a receiver array, and provides recommendations to account for detection range during experimental design, analysis and data interpretation.
Size, Sex And Geographic Variation in the Diet of the Tiger Shark, Galeocerdo Cuvier, From Western Australian Waters
- C. Simpfendorfer, A. Goodreid, R. McAuley
- Environmental ScienceEnvironmental Biology of Fishes
- 1 May 2001
The high level of occurrence of dugongs and turtles in the diet of G. cuvier, relative to their abundance, suggests that shark predation may play an important role in regulating populations of these species.
Estimation of short-term centers of activity from an array of omnidirectional hydrophones and its use in studying animal movements
- C. Simpfendorfer, M. Heupel, R. Hueter
- Environmental Science
- 2002
The utility of the method was assessed using data from a study of neonate blacktip sharks, with results equivalent to a short-term center of activity rather than a precise estimate of location at a single time.
Estimation of mortality of juvenile blacktip sharks, Carcharhinus limbatus, within a nursery area using telemetry data
- M. Heupel, C. Simpfendorfer
- Environmental Science
- 1 April 2002
The results suggest that young sharks are most vulnerable to all types of mortality during this period, and that Sharks that survived beyond the first 15 weeks successfully left the nursery and were presumed to have migrated southward during fall months.
Movement and distribution of young bull sharks Carcharhinus leucas in a variable estuarine environment
- M. Heupel, C. Simpfendorfer
- Environmental Science
- 5 February 2008
Since bull sharks are euryhaline, results suggest that they may select environmental conditions via movement, possibly to reduce energetic costs associated with osmoregulation.
Sharks in nearshore environments: models, importance, and consequences
- D. Knip, M. Heupel, C. Simpfendorfer
- Environmental Science
- 8 March 2010
How different species utilise nearshore areas and how they overcome the challenges they face in inhabiting these areas are reviewed to provide a better understanding of how sharks use nearshore environments and assist in making conservation and management decisions for these regions.
The importance of research and public opinion to conservation management of sharks and rays: a synthesis
- C. Simpfendorfer, M. Heupel, M. Heupel, W. White, N. Dulvy
- Environmental Science
- 21 July 2011
The present paper examines the growing need for research for conservation management of sharks and rays by synthesising information presented in this Special Issue from the 2010 Sharks International Conference and by identifying future research needs, including topics such as taxonomy, life history, population status, spatial ecology, environmental effects and human impacts.
Population status of 14 shark species caught in the protective gillnets off KwaZulu-Natal beaches, South Africa, 1978-2003
- S. Dudley, C. Simpfendorfer
- Environmental Science
- 31 March 2006
The potential effect of the shark nets was assessed to be high for two species (Carcharhinus obscurus and Carcharias taurus, neither of which showed declines in catch rate or length), because of very low intrinsic rates of population increase.
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