Biology subjects

Iturralde-Polit, P.

Publications and source records attributed to Iturralde-Polit, P..

2 recordsLinked to original sources

bioRxiv2023

Variation in echolocation call emission of Neotropical insect-eating bats in response to shifting ambient temperatures

The sensory systems of animals are essential for them to respond to environmental cues and signals. However, their functionality might be altered by climate change. Most bats, for example, rely on acoustic signal emission for acquiring food, but their high-frequency echolocation calls are strongly attenuated in the air. Attenuation in air changes with changing weather conditions, which can lead to shifts in echo-based prey detection distance. However, bats adjust call parameters to the task and environment, and this behavioural plasticity may also help them to counteract potential increases in sound attenuation to keep echo detectability constant. We explored this ability in a community of insectivorous bats in a montane forest of Costa Rica. We recorded bat echolocation calls in response to experimentally increased temperatures, simulating intermediate and arguably realistic projected climate change scenarios. We calculated atmospheric attenuation and detection distance for each temperature and echolocation call. We found some changes in source level and call duration, yet not in peak frequency, and responses were not consistent across species with increasing atmospheric attenuation. This might be explained by several non-mutually exclusive reasons, including that the experimental increase in temperature and change of atmospheric attenuation were not sufficient to affect close-range prey detection. Ultimately, this study contributes to our understanding of sensory system adaptation under the pressure imposed by climate change. SUMMARY STATEMENTStudying adjustments in bats call parameters can reveal responses to the pressure imposed by climate change.

ecology↗

bioRxiv2020

The energetics of social signaling during roost location in Spix's disc-winged bats

Long-term social aggregations are maintained by multiple mechanisms, including the use of acoustic signals, which may nonetheless entail significant energetic costs. To date, however, no studies have gauged whether there are significant energetic costs to social call production in bats, which heavily rely on acoustic communication for a diversity of social tasks. We measure energetic expenditure during acoustic signaling in Spixs disc-winged bats (Thyroptera tricolor), a species that commonly uses contact calls to locate the ephemeral furled leaves that they use for roosting. To determine the cost of sound production, we measured oxygen consumption using intermittent-flow respirometry methods, with and without social signaling. Our results show that the emission of contact calls significantly increases oxygen consumption; vocal individuals spent, on average, 12.42 kJ more during social signaling trials than they spent during silent trials. Furthermore, production of contact calls during longer periods increased oxygen consumption for males but not for females. We also found that as resting metabolic rates increased in males, there was a decreasing probability that they would emit response calls. These results provide support to the "allocation model", which predicts that only individuals with lower self-maintenance costs can afford to spend energy in additional activities. Our results provide a step forward in our understanding of how physiology modulates behavior, specifically how the costs of call production and resting metabolic rates may explain the differences in vocal behavior among individuals. Summary StatementSpixs disc-winged bats constantly produce contact calls while searching for roosts, which we show significantly increases an individuals metabolic rate.

physiology↗