Design of instrumentation for metabolic monitoring of the Adélie penguin : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physics at Massey University

Abstract

The motivating question for the work described in this thesis was "How does the Adélie penguin cope with cold?" It was reasoned that the time-scale of temperature changes in Antarctica precluded all but metabolic and physiological responses. To determine these, a system capable of measuring and recording these biological variables in the penguins natural environment, was designed. A device, based on the principles of near infrared spectroscopy, was developed that could measure the relative oxygen saturation of haemoglobin and the reduction state of cytochrome oxidase as well as heart rate and blood volume. The completed device was housed in a black, waterproof, plastic container, measuring 65mm x 92mm x 25mm and weighing 132.7g. Co-ordination of measurements was achieved with operating system-like control software implemented in Motorola HC11 assembly code. Synchronous detection was used for signal acquisition and a pulse algorithm, implemented in assembly code, allowed real time pulse measurement from the input signals. Programs were written in Matlab and C++ to investigate the characteristics and limits of these techniques. Preliminary testing of the device on human subjects successfully showed changes in metabolic state as a result of physical activity. The results of field testing on Adélie penguins were unable to answer the original question due to a number of physical factors. However, the success of human trials suggests that, with modification and improvement, the device has potential as a valuable research instrument, applicable to a variety of other species.