Although the bedrock of our research is good, ‘old fashioned’ behavioural observations; spending long hours dawn til dusk collecting behavioural data on the known individual seals that we observe, we are always trying to understand the behaviour we see more fully. Part of that includes trying to get a handle on the physiological processes and differences between individuals that might drive their different responses to particular situations. In order to do this we sometimes use rather more high-tech approaches – using bio-telemetry devices to get additional information on our seals. This year, as for last year, we are deploying heart rate monitors to our study seals, along with accelerometers. The heart rate monitors transmit data on individual seal’s heart rates as they engage in the various behaviours, and the signal from the transmitters can be picked up over 100m away from the seals – so we don’t have to be anywhere near the seals, and they can get on with their normal behaviour. The idea here is to understand better how individual seals perceive and react to stressful situations – such as aggression with their neighbours, or when mums have to leave their pup for a while to find a pool to drink from.
The accelerometers are for Courtney’s research. They provide sub-second data on the 3-dimensional movements of the seal. With these data Courtney hopes to be able to use the accelerometers to provide a far more detailed account of the seals’ behaviour – not just during the daylight hours during which we are able to watch the seals (only about one-third of the day at this time of year!), but 24/7 detailed data on behaviour and individual differences in behaviour.
One problem with using these bio-telemetry tagging devices in a wild animal study, is that the tags have to be engineered to a high specification in terms of ruggedness, and ability to cope with extreme conditions. Seals can really put these device through the mill – 200+ kg of seal, crushing the device against rocks, or fighting with each other, or submerging them in freezing cold, thick, oozing mud pools full of other seals! Yes, these ‘tags’ have to be tough.