Dr Patrick Miller, Dr Vincent Janik, Dr Sascha Hooker, Dr Martin Biuw and Professor Ian Boyd.
University of St Andrews.
High-tech listening devices and acoustic playback experiments allow researchers at the Sea Mammal Research Unit (SMRU) a National Environment Research Council (NERC) collaborative centre at the University of St Andrews to investigate how deep-sea mammals communicate. 'These animals live in dark, cold, high pressure conditions', explains Vincent Janik. 'In such an environment, it is crucial that they have an effective and fail-safe system to stay in touch with each other. We found that dolphins have developed recognition signals that are almost as versatile as human names'.
'We record behaviour patterns, sounds emitted and the physical characteristics of the surrounding waters', explains Sascha Hooker. 'Behaviour patterns provide a good measure of the health of sea mammals and the health of the ecosystems they live in'. When elephant seals and sperm whales glide passively through the water, their body fat or blubber alters their buoyancy, which in turn influences their gliding patterns. 'Changes in these movement patterns indicate changes in the amount of food energy stored as blubber within an animal', says Patrick Miller.
Images and other data from tagged animals have revealed previously unknown behaviour in some species. Most animals make use of their buoyancy to get a free ride to the surface, but the Antarctic Fur Seal makes itself less buoyant by blowing bubbles as it comes up for air. Why would the seal make its ascent so much harder? Sascha suggests that it may prevent blackouts as they return to the surface, a well-known problem experienced by human 'breath-hold' divers.
Despite the extreme conditions, tracking devices that record sound, photos and video have successfully been attached to a varie