Biology subjects

Voigt, C. C.

Publications and source records attributed to Voigt, C. C..

4 recordsLinked to original sources

bioRxiv2023

Urbanisation generates multiple trait syndromes for terrestrial taxa worldwide

Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats and, potentially, to local extinctions. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities and surrounding landscapes. Using a dataset with site-level occurrence and trait data of 5302 species from six terrestrial fauna taxonomic groups across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy consistently showing the strongest response. The effect of urbanisation on community trait composition is strongest at the largest spatial scale considered, and more closely linked to landscape composition (% urban) than arrangement (aggregation), although latitude and climatic variables remain a stronger influence. This study did not find evidence in support of a global urban taxa syndrome, but instead we suggest that there are four general urban trait syndromes, with resources associated with reproduction and diet likely to be driving patterns in traits associated with mobility and body size. Functional diversity measures showed a wide range of responses, leading to a shift in trait space that is most likely driven by the distribution and abundance of critical resources, and the urban trait syndrome displayed by individual species within a community. Further research is required to understand the interactions between the four general urban trait syndromes, resource distribution and abundance and changes in functional diversity of taxa at different spatial and temporal scales. Maximising opportunities to support species within taxa groups with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation at the taxa level, and helps ensure that urban environments have the ecological capacity to respond to challenges such as climate change, further habitat fragmentation and loss, and other disruptions. These actions are critical if we are to reframe the role of cities in global biodiversity loss.

ecology↗

bioRxiv2022

Migration strategy varies with novel environment response in common noctule bats

Global ecosystems are changing dramatically due to land transformation and climate change. Global change is a particular challenge for migratory animals that rely on multiple stepping stones on their journeys. Migratory animals have a range of strategies to accomplish this, but not all of these strategies may be appropriate for the challenges ahead. Understanding the variation in migratory strategies and their behavioural correlates is therefore critical to understand how vulnerable species will be in the future, especially in endangered and elusive taxa such as bats. Here, we combined isotopic geolocation with an in-situ behavioural assay to investigate whether behavioural responses to a roost-like novel environment correlated with variation in migration strategies (local or distant origin based on isotopic geographic assignments), in the partially migratory bat, Nyctalus noctula. We quantified emergence behaviour, spatial activity, and echolocation call activity. Local bats were more likely to emerge into the novel environment than bats from more distant origins. However, local and distant bats did not differ in spatial activity and acoustic exploration (relative call activity per space unit). Our findings indicate that local bats may more pro-actively cope with novelty, but that acoustic exploration is equally important for local and migratory bats during explorations.

animal behavior and cognition↗

bioRxiv2022

A playback paradox? Nathusius' bats, Pipistrellus nathusii, bypass mating and fueling opportunities on migratory transit flights

In late summer, migratory bats of the temperate zone face the challenge of accomplishing two energy-demanding tasks almost at the same time: migration and mating. Both require information and involve search efforts, such as localizing prey or finding potential mates. In non-migrating bat species, playback studies showed that listening to vocalizations of other bats, both con-and heterospecifics, may help a recipient bat to find foraging patches and mating sites. However, we are still unaware of the degree to which migrating bats depend on con- or heterospecific vocalizations for identifying potential feeding or mating opportunities during nightly transit flights. Here, we investigated the vocal responses of Nathusius pipistrelle bats, Pipistrellus nathusii, to simulated feeding and courtship aggregations at a coastal migration corridor. We presented migrating bats either feeding buzzes or courtship calls of their own or a heterospecific migratory species, the common noctule, Nyctalus noctula. We expected that during migratory transit flights, simulated feeding opportunities would be particularly attractive to bats, as well as simulated mating opportunities which at the same time indicate suitable roosts for a stopover. However, we found that the echolocation call activity of P. nathusii decreased during the playback of conspecific feeding buzzes and courtship calls, yet the call activity remained unaffected when heterospecific call types were broadcast. Our results therefore suggest that while on migratory transits, P. nathusii circumnavigate conspecific feeding and mating aggregations, possibly to save time or to reduce the risks associated with social interactions. This avoidance behavior could be a result of optimization strategies by P. nathusii when performing long-distance migratory flights.

animal behavior and cognition↗

bioRxiv2020

In situ novel environment assay reveals acoustic exploration as a repeatable behavioral response in migratory bats

Integrating information on species-specific sensory perception together with spatial activity provides a high-resolution understanding of how animals explore environments, yet frequently used exploration assays commonly ignore sensory acquisition as a measure for exploration. Echolocation is an active sensing system used by hundreds of mammal species, primarily bats. As echolocation call activity can be reliably quantified, bats present an excellent animal model to investigate intra-specific variation in environmental cue sampling. Here, we developed an in situ roost-like novel environment assay for tree-cave roosting bats. We repeatedly tested 52 individuals of the migratory bat species, Pipistrellus nathusii, across 24 hours, to examine the role of echolocation when crawling through a maze-type arena and test for consistent intra-specific variation in sensory-based exploration. We reveal a strong correlation between echolocation call activity and spatial activity. Moreover, we show that during the exploration of the maze, individuals consistently differed in spatial activity as well as echolocation call activity given their spatial activity, a behavioral response we term acoustic exploration. Acoustic exploration was correlated with other exploratory behaviors, but not with emergence latency. We here present a relevant new measure for exploration behavior and provide evidence for consistent (short-term) intra-specific variation in the level at which wild bats collect information from a novel environment.

animal behavior and cognition↗