Biology subjects

Hardin, F. O.

Publications and source records attributed to Hardin, F. O..

3 recordsLinked to original sources

bioRxiv2023

Fortune may favor the flexible: Environment-dependent behavioral shifts in invasive coqui frogs

Biological invasions are a major driver of global biodiversity loss, impacting endemic species, ecosystems, and economies. While the influence of life history traits on invasive success is well-established, the role of behavior in the invasive potential of animals is less studied. The common coqui frog, Eleutherodactylus coqui, is a highly successful invader in Hawaii. We build on previous research characterizing changes in physiology and morphology to explore behavioral variation across the invasive range of coqui in Hawaii. We hypothesized that behavioral traits contributing to invasion expansion would be reflected in behavioral differences at the invasive center versus invasive edge. To investigate whether differences in the field represent local adaptation or behavioral plasticity, we additionally evaluated behavior following acclimation to a shared laboratory environment. While we identified only subtle behavioral variation among populations in the field, we found that individuals from all populations became less bold, active, and exploratory in the laboratory, converging on a similar behavioral phenotype. Alongside previous work, our results suggest that coqui adjust their behavior to local environmental conditions across their invasive range, and that behavioral flexibility may contribute to invasive success.

animal behavior and cognition↗

bioRxiv2023

Individual Behavioral Variability Across Time and Contexts in Dendrobates tinctorius Poison Frogs

Consistent individual differences in behavior ("animal personality") have consequences for individual fitness, evolutionary trajectories, and species persistence. Such differences have been documented across a wide range of animals, though amphibians are generally underrepresented in this research area. The aim of our study was to examine consistent individual differences in Dyeing poison frogs, Dendrobates tinctorius. We evaluated repeatability in behaviors including activity, exploration, and boldness to assess consistency of behaviors across different temporal, experimental, and environmental contexts. We found repeatability in activity and exploration across time and contexts. In contrast, we observed context-specific behavior for our metrics of boldness, with consistent individual differences only for some measures. Further, while activity and exploration displayed consistent correlations across contexts, relationships between activity and boldness were context dependent. Our findings document the presence of consistent individual differences in behavior in D. tinctorius poison frogs, and also reveal context-dependent behavioral differences, highlighting the complex relationship between consistent individual differences and context-specific responses in animal behavior. Statement of SignificanceThe concept of animal personality centers on the existence of consistent individual differences in behavior. However, behavioral responses can depend on context, and consistent individual differences in one context do not guarantee consistent differences in another. To address this question, we assessed activity, exploration, and boldness in captive-bred poison frogs (Dendrobates tinctorius) across time and environmental contexts. Our comprehensive approach revealed consistent individual differences in some behaviors and context-specificity in others. While activity and exploration were generally repeatable and correlated with one another, boldness was not. Especially in view of the emphasis on measures of boldness in the animal personality literature, our findings emphasize the importance of reiterative and holistic approaches in the study of animal behavior.

animal behavior and cognition↗

bioRxiv2020

Secondhand homes: Woodpecker cavity location and structure influences secondary nester's success.

O_LIUnderstanding how ecosystem engineers influence other organisms has long been a goal of ecologists. Woodpeckers select nesting sites with high food availability and will excavate and then abandon multiple cavities through their lifetime. These cavities are crucial to secondary cavity nesting birds (SCB) that are otherwise limited by the availability of naturally occurring cavities. C_LIO_LIOur study examined the role food resources have on the nest site location and home range size of woodpeckers, and the respective influence woodpeckers and the construction of cavities have on the nesting success of SCB. C_LIO_LIUsing five years of avian point count data to locate golden-fronted woodpeckers (GFWO: Melanerpes aurifrons), we correlated insect availability with GFWO home range size and determined differences in insect availability between GFWO occupied and unoccupied sites, while recording nesting success (success: [≥] 1 fledgling) for the GFWO and common SCB in south Texas: Black-crested Titmouse (Baeolophus atricristatus), Ash-throated Flycatcher (Myiarchus cinerascens), Brown-crested Flycatcher (Myiarchus tyrannulus), and Bewicks Wren (Thryomanes bewickii). We used model averaging to fit species-specific logistic regression models to predict nest success based on cavity metrics across all species. C_LIO_LISites occupied by GFWO had a higher biomass of insects in orders Coleoptera, Hymenoptera, and Orthoptera than unoccupied sites, and there was a negative correlation between the availability of these insect orders and home-range size. GFWO had increased nest success in trees with increased vegetation cover and lower levels of decay, while SCB had higher levels of nesting success in abandoned GFWO cavities opposed to naturally occurring ones, and in trees with low decay. C_LIO_LIOur results suggest that SCB may be drawn to nest in abandoned woodpecker cavities where they have higher rates of nest success compared to natural cavities. Additionally, the prevalence for GFWO to excavate cavities in trees with lower levels of decay contradicts previous literature and may indicate a novel temperature trade-off, with live trees requiring more energy to excavate, but providing more protection from high breeding season temperatures in arid and semi-arid areas. C_LI

ecology↗