Biology subjects

Kloepper, L. N.

Publications and source records attributed to Kloepper, L. N..

3 recordsLinked to original sources

bioRxiv2023

Tail length in male versus female fox squirrels (Sciurus niger)

BackgroundArboreal mammals rely on their tails to aid in balance while maneuvering complex habitats. Females experience additional challenges to locomotion due to reproductive demands including altered body mass and/or body shape, which leads to shifts in center of mass. Without compensation, this may increase the risk of losing balance and falling out of trees. We tested the hypothesis that female squirrels have longer tails than males to offset shifts in center of mass that may result from pregnancy. ResultsMorphological data were collected from 57 fox squirrels (Sciurus niger) in northern Indiana in summer 2019 and 2021. Although our initial t-test analysis of relative tail length (RTL) showed that female squirrels had longer tails than males (p = 0.02), a subsequent ANCOVA that controlled for effect of body length indicated no significant effect of sex on tail length (p = 0.42). ConclusionsThe results of this study demonstrate the potential impacts of different analysis methods on overall understanding of organismal functional morphology and are an important addition to the literature on tail form and function, which remains poorly understood compared to other appendages.

zoology↗

bioRxiv2022

BatCount: A software program to count moving animals

One of the biggest challenges with species conservation is collecting accurate and efficient information on population sizes, especially from species that are difficult to count. Bats worldwide are declining due to disease, habitat destruction, and climate change, and many species lack reliable population information to guide management decisions. Current approaches for estimating population sizes of bats in densely occupied colonies are time-intensive, may negatively impact the population due to disturbance, and/or have low accuracy. Research-based video tracking options are rarely used by conservation or management agencies for animal counting due to the perceived training required to operate. In this paper, we present BatCount, a free software program created in direct consultation with end-users designed to automatically count aggregations of bats at cave roosts with a streamlined and user-friendly interface. We report on the software package and provide performance metrics for different recording habitat conditions. Our analysis demonstrates that BatCount is an efficient and reliable option for counting bats in flight and has important implications for range- and species-wide population monitoring. Furthermore, this software can be extended to count any organisms moving across a camera including birds, mammals, fish or insects.

zoology↗

bioRxiv2022

Steering clear of the confusion effect: aerial predators target fixed points in dense prey aggregations

Collective behaviours are widely assumed to confuse predators, but empirical support for a confusion effect is often lacking, and its importance must depend on the predators targeting mechanism. Here we show that raptors steer attacks on swarming bats by turning towards a fixed point in the swarm, rather than by using closed-loop pursuit of an individual. Any prey that the predator is on a collision course with will appear on a constant bearing, so target selection emerges naturally from the geometry of a collision. Our results show how predators can simplify the demands on their sensory system by decoupling steering from targeting when grabbing prey from a dense swarm. We anticipate that the same tactic will be used against flocks and schools across a wide range of taxa, in which case a confusion effect is paradoxically more likely to occur in attacks on sparse groups, for which steering and targeting cannot be decoupled.

animal behavior and cognition↗