Reactions of Hector's dolphins to acoustic gillnet pingers

Authors:

Stone, G.S., Cavagnaro, L., Hutt, A., Kraus, S., Baldwin, K., Brown, J.

Year:

2000

Journal/Publisher Name:

Department of Conservation, New Zealand

Page #s:

http://www.cetaceanbycatch.org/Papers/stone.pdf

Publisher Address:

PO Box 10-420 Wellington, New Zealand

White Dukane pingers with a fundamental frequency of 10kHz and harmonies of up to 160 kHz, elicited the strongest response from Hector's dolphins, compared to the black Pice and red Dukane pingers. More than half (62.5%) of the dolphins exhibited avoidance when exposed to the white pinger. However, no significant differences between pingers were found in the rate of echolocation clicks per dolphin or dolphin group, or among the peak frequencies of subset clicks.
Field Studies:

Location	Fishing gear	Reduction technique	Bycatch species	Effect on bycatch species	Catch	Effect on target catch	Type
Akaroa Harbour, New Zealand	Gillnets	Acoustic pingers	Small Cetaceans (maximum length < 7.5 meters)	62.5% of individuals elicited avoidance behavior (using white Dukane pingers)	None reported	None reported	In the wild