Dolphin continuous auditory vigilance for five days.
The present report describes the first study of continuous vigilance in dolphins. Two adult bottlenose dolphins (Tursiops truncatus), WEN (male) and SAY (female), maintained a very high detection rate of randomly presented, infrequent, 1.5-s target tones in a background of frequent 0.5-s equal-amplitude tones over five continuous 120-h sessions. The animals were able to maintain high levels (WEN 97, 87, 99%; SAY 93, 96%) of target detection without signs of sleep deprivation as indicated by behavior, blood indices or marked sleep rebound during 24 h of continuous post-experiment observation. Target response time overall (F = 0.384; P = 0.816) did not change between day 1 and day 5. However, response time was significantly slower (F = 21.566, P = 0.019) during the night (21.00-04.00 h) when the dolphins would have ordinarily been resting or asleep.
Ridgway
Sam
S
Space and Naval Warfare Systems Center, San Diego, Code 235, 53560 Hull Street, San Diego, CA 92152-5001, USA. sridgway@UCSD.edu
Carder
Don
D
Finneran
James
J
Keogh
Mandy
M
Kamolnick
Tricia
T
Todd
Mark
M
Goldblatt
Allen
A
D000818:Animals; D001307:Auditory Perception; D050681:Bottle-Nosed Dolphin / Q000502:physiology*; D002940:Circadian Rhythm; D005260:Female; D008297:Male; D011930:Reaction Time; D012119:Respiration; D012890:Sleep; D013997:Time Factors; D014851:Wakefulness