Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands)
Article first published online: 28 APR 2008
© 2008 The Authors. Journal compilation © 2008 British Ecological Society
Journal of Animal Ecology
Volume 77, Issue 5, pages 936–947, September 2008
How to Cite
Aguilar Soto, N., Johnson, M. P., Madsen, P. T., Díaz, F., Domínguez, I., Brito, A. and Tyack, P. (2008), Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands). Journal of Animal Ecology, 77: 936–947. doi: 10.1111/j.1365-2656.2008.01393.x
- Issue published online: 13 AUG 2008
- Article first published online: 28 APR 2008
- Received 23 December 2007; accepted 30 January 2008; Handling Editor: Graeme Hays
- deep water ecosystem;
- foraging ecology;
- marine mammal;
- pilot whale;
- swimming speed
- 1Empirical testing of optimal foraging models for breath-hold divers has been difficult. Here we report data from sound and movement recording DTags placed on 23 short-finned pilot whales off Tenerife to study the foraging strategies used to catch deep-water prey.
- 2Day and night foraging dives had a maximum depth and duration of 1018 m and 21 min. Vocal behaviour during dives was consistent with biosonar-based foraging, with long series of echolocation clicks interspersed with buzzes. Similar buzzes have been associated with prey capture attempts in other echolocating species.
- 3Foraging dives seemed to adapt to circadian rhythms. Deep dives during the day were deeper, but contained fewer buzzes (median 1), than night-time deep dives (median 5 buzzes).
- 4In most deep (540–1019 m) daytime dives with buzzes, a downward directed sprint reaching up to 9 m s−1 occurred just prior to a buzz and coincided with the deepest point in the dive, suggestive of a chase after escaping prey.
- 5A large percentage (10–36%) of the drag-related locomotion cost of these dives (15 min long) is spent in sprinting (19–79 s). This energetic foraging tactic focused on a single or few prey items has not been observed previously in deep-diving mammals but resembles the high-risk/high-gain strategy of some terrestrial hunters such as cheetahs.
- 6Deep sprints contrast with the expectation that deep-diving mammals will swim at moderate speeds optimized to reduce oxygen consumption and maximize foraging time at depth. Pilot whales may have developed this tactic to target a deep-water niche formed by large/calorific/fast moving prey such as giant squid.