What different things do animals do on hot days compared to cooler days? How much do they move around at night, if at all? These are some of the questions Wageningen University (Netherlands) PhD Student Anil Kumar Shrestha is hoping to answer with the help of modern technology, five wildebeest, five eland and five impala.
Anil, a medical team from the School of Physiology at the University of Witwatersand's medical school and staff from the SANParks Veterinary Wildlife Services fitted various devices to these animals that will record their movement, body temperature and the ambient temperature. Drs Peter Buss and Danny Govender, vets from SANParks, were on hand to anaesthetise and monitor the animals while the medical team implanted the data loggers. These were placed under the muscle layers on the side of the animal's abdomen.
The data logger will record the movement of the animal as well as its body temperature. At the same time, Anil and his team fitted collars with ‘mini-weather stations' around each of the animal's necks. These devices will monitor external factors such as solar radiation and the environmental temperature of the surrounds in which the animal finds itself. It will also pick up the information from the data loggers, which is then sent to Anil through a system referred to as VHF download.
In addition, Anil will place a mobile weather station in the study area to also record external elements such as environmental temperature and solar radiation. In the end, Anil aims to relate the animals' activity and body temperature to the external climatic conditions, including environmental temperature. In this way he hopes to determine when these animals are most active, what determines this activity and what influence external factors like temperature could have on their movement.
A similar study will be done in the Eastern Cape, which in contrast to the hot-all-year-round weather at Mapungubwe on the northern borders of South Africa, has mild summers and cold winters. "One of the advantages in using this method, is that ‘observer effects' on the study animals can be mitigated through the remote sensing technology," says Danny. In addition, Anil hopes to get some idea of how animals respond to changes in climate and how this may relate to the bigger question of climate change.
The study will continue over twelve months to ensure that data obtained during all seasons are included in the analysis. Peter says the animals have recovered well from the anaesthesia and surgical procedure, and the data loggers have already started transmitting information.
By Lynette Strauss