Meeting Abstract
Energy is the currency of life, where a surplus allows for survival and reproduction and a long-standing debt leads to sickness or death. Real-time monitoring of energy expenditures in free-living animals has been relatively limited by available technology. Continuous tone radio transmitters that have been specially modified to detect heart rate, however, allow for real-time estimation of energy expense in free-living, behaving animals, as well as for close monitoring of behavior. Red crossbills live at northern latitudes and/or high elevations year-round and can breed opportunistically throughout much of the year. They therefore offer a unique opportunity to examine the eco-physiology of different life cycle stages under drastically variable seasonal conditions. Here we present heart rate data from free-living breeding and non-breeding red crossbills in the summer and winter. We discuss these variables in the context of red crossbills’ unique opportunistic and nomadic annual schedules and the highly seasonal conditions of our field site in Grand Teton National Park.
