A team of researchers from Konstanz has monitored the heart rate of bats, focusing on the common noctule bat species. They attached tiny heart rate transmitters to the bats and recorded their heartbeats during flights. This study, published in Proceedings of the Royal Society B, offers insights into how bats manage their energy consumption and survive in their environment.
Scientists from the Max Planck Institute of Animal Behavior (MPI-AB) and the University of Konstanz conducted a unique study on male common noctule bats, aiming to determine their daily energy consumption and how it varies throughout the year.
Lead author of the study, Lara Keicher, highlights the importance of understanding the energy needs of bats to predict their survival in changing climates.
Monitoring Heart Rates
To measure energy consumption, the researchers equipped the bats with miniature heart rate transmitters weighing less than a gram. These transmitters emitted the bats’ heartbeats as an audio signal, which was recorded using a radio receiver within proximity of the bats.
Keicher notes that tracking heartbeats during the day was easier as bats rested, but the team also flew alongside the bats in an airplane at night to monitor their heart rates during nocturnal flights.
Energy Conservation Strategies
The study revealed that bats can reach heart rates of around 900 beats per minute during flight, adjusting their metabolism to manage energy consumption in different seasons.
Male common noctule bats were found to consume significantly more energy in summer due to increased activity and mating behavior. They exhibit a unique energy-saving state in spring called “torpor,” where heart rate drops to six beats per minute and quickly ramps up when they wake up.
In contrast, during summer, males forgo torpor to invest energy in mating readiness, hunting extensively to replenish energy reserves.
The findings shed light on bats’ energy challenges and behavior, aiding in predicting how environmental changes may impact their survival in the future.
Dina Dechmann, the senior author of the study, emphasizes the importance of protecting bat species and using research findings to develop conservation strategies.