BODY TEMPERATURE REGULATION
Animals have the ability to control their body temperature through both physiological and behavioural mechanisms. This capacity to adapt to the thermal environment determines the amount of energy available for maintenance, foraging, reproduction and survival. Endotherms, such as birds and mammals are often considered to be homeothermic, because they maintain a relatively constant body temperature. However, many endotherms allow their temperature to change as a strategy to conserve energy when faced with a thermal challenge.
Alternatively, species may manage body temperature by adopting different postures, sharing body heat (social thermoregulation), seeking favourable microclimates or by migrating over large distances. Behavioural thermoregulation of this kind can be vitally important at critical life-cycle stages, such as when young, or when moulting reduces insulation, and may be affected by human disturbance.
Our research aims to gain detailed understanding of the energetic costs of different thermoregulation strategies, and their evolutionary consequences.
STRESS & WELFARE
Body surface temperature provides important information about health and wellbeing, both in captivity and the wild, indicating how individuals are coping with their environment.
High heat loss from the body requires increased metabolism which depletes fat stores, affecting body condition. Changes in metabolism may also be influenced by stress hormone secretion, which can reduce blood-flow to the body surface, cooling the skin. Additionally, animals respond to acute stress or pain with rapid adjustments in blood distribution, which can be detected through changes in body surface temperature.
Surface temperature changes can be monitored non-invasively in realtime using infrared thermal imaging cameras. This means thermal imaging can be used to heat loss, body condition and stress state, without the need for capture or handling. Our group is at the forefront of efforts to develop non-invasive thermal imaging techniques for assessing physiological stress and general welfare in farm, laboratory and wild animals.
MEASURING BODY TEMPERATURE
Body temperature is a key parameter in physiological, behavioural and ecological research. However, temperature measurements on free-ranging animals remain challenging.
Internal temperature may be sampled using thermometry, surgically implanted loggers or transmitters, or ingested gastrointestinal devices. Less invasive approaches measure peripheral temperature with subcutaneous passive integrated transponder tags or skin surface-mounted radio transmitters and data loggers, or use infrared thermography to record surface temperature.
We seek to develop and enhance the use of this entire range of techniques, exploring their strengths and limitations for assessment of body temperature under field conditions.