MEPS 429:261-275 (2011) - DOI: https://doi.org/10.3354/meps09080
Spatial and temporal movement patterns of a multi-species coastal reef shark aggregation
Conrad W. Speed1,2,*, Mark G. Meekan1, Iain C. Field2,3, Clive R. McMahon2, John D. Stevens4, Frazer McGregor5, Charlie Huveneers6,7, Yuval Berger1, Corey J. A. Bradshaw7,8
ABSTRACT: The quantification of spatial and temporal movement patterns of coral reef sharks is important to understand their role in reef communities and to aid the design of conservation strategies for this predatory guild. We observed 4 species of reef sharks aggregating in an inshore bay in the north of Western Australia for over 2 yr, using acoustic telemetry and visual censuses to examine how they partitioned this site in space and time. We fitted 58 sharks with acoustic transmitters: Carcharhinus melanopterus (36), C. amblyrhynchos (11), Negaprion acutidens (7) and Triaenodon obesus (4). Aggregations consisted primarily of C. melanopterus, although C. amblyrhynchos and N. acutidens were often present. We observed aggregations by visual census in summer (maximum of 44 sharks). Detections were highest during warmer months (Sep to Mar) for all species, although some individuals showed year-round residency. C. melanopterus, C. amblyrhynchos and N. acutidens had strong diel patterns of attendance at the aggregation site. Peak daily detections occurred from 13:00 to 14:00 h local time for C. melanopterus and C. amblyrhynchos; juvenile C. melanopterus and N. acutidens peaked at 05:00 and 10:00 h, respectively. There was considerable spatial overlap of core areas of use (50% kernel density estimates) at the northern end of the bay by all species; the southern end was used primarily by C. melanopterus and N. acutidens. Aggregations of C. melanopterus and C. amblyrhynchos consisted mainly of adult females, some of them pregnant. Courtship behaviour in C. melanopterus and T. obesus suggests that these aggregations are related to reproduction. All species displayed inter-annual site fidelity. The long-term presence of juvenile C. melanopterus and N. acutidens also suggests that this bay provides suitable conditions for younger age classes.
KEY WORDS: Habitat partitioning · Site fidelity · Residency · Acoustic telemetry · Visual census · Management · Habitat use · Diel patterns
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Full text in pdf format Supplementary material | Cite this article as: Speed CW, Meekan MG, Field IC, McMahon CR and others (2011) Spatial and temporal movement patterns of a multi-species coastal reef shark aggregation. Mar Ecol Prog Ser 429:261-275. https://doi.org/10.3354/meps09080 Export citation Share: Facebook - - linkedIn |
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