Publication Abstract

Generation 5 data storage tags, GPS and developed methodology for studying the hydrostatic pressure environment of the Juvenile lemon shark (Negaprion brevirostris).

Generation 5 data storage tags, GPS and developed methodology for studying the hydrostatic pressure environment of the Juvenile lemon shark (Negaprion brevirostris).

Smith, LE; Gruber, SH; Kessel, S; Metcalfe*, J; Fraser, PJ

Depth reception is of great importance to aquatic species. Pioneering laboratory work at Aberdeen University in Scotland identified a hydrostatic sensor in a shark for the first time. Vestibular hair cells in the labyrinth which code angular acceleration were also shown to respond to small changes in hydrostatic pressure (Fraser and Shelmerdine, 2002), with clear effects following small step changes in pressure and to slow sinusoidal cycles of pressure. A field study appeared to show juvenile sharks responding to a change in barometric pressure and departing to deeper water as a storm approached (Heupel et al, 2003). Fieldwork to investigate the normal usage of this recently discovered sensor was conducted from August through to October 2006 in South Bimini, Bahamas, (N 25ø41.87, W 79ø17.787) at the Bimini Biological Field Station (B.B.F.S.). This addressed whether Negaprion showed significant changes in depth over time, and how any depth changes related to atmospheric and tidal cycles. 9 Juvenile lemon sharks <1 m previously fitted with internal acoustic transmitters and pit tags were actively tracked using hydrophone and receiver equipment. Once an accurate position could be pinpointed for a shark a gill net was set and the shark caught.

Reference

Smith, LE; Gruber, SH; Kessel, S; Metcalfe*, J; Fraser, PJ (2007) Generation 5 data storage tags, GPS and developed methodology for studying the hydrostatic pressure environment of the Juvenile lemon shark (Negaprion brevirostris). Proceedings of the Annual Meeting - Institute of Navigation 253-263 2007

Smith, LE; Gruber, SH; Kessel, S; Metcalfe*, J; Fraser, PJ

Proceedings of the Annual Meeting - Institute of Navigation 253-263 2007