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Determining whether organisms have preferences for certain aspects of the habitat is important for understanding the process of habitat selection. Anolis lizards (anoles) have evolved to occupy distinct parts of the arboreal environment. Depending on the population or species, anoles perch on different aspects of the structural habitat varying in diameter, height, and type of substrate. We used laboratory and mesocosm trials to assess whether 2 species of Anolis lizards have preferences for the diameter and type of substrate they use for perching. Results reveal A. cristatellus and A. sagrei both prefer larger diameter perches. Lizards from natural forests and urban populations showed no difference in perch-diameter preference. In contrast, A. sagrei from an urban site overwhelmingly preferred to perch on wood substrates over polyvinyl chloride and metal ones. The larger diameter and wood substrates preferred by anoles in our trials should confer increased locomotor performance for these species based on previous studies. Rapid environmental change caused by humans can decouple the relationship between habitat preferences and fitness, so it is essential to test for changing preferences in organisms that experience urbanization and other forms of global change. [ABSTRACT FROM AUTHOR]

Foraging decisions reflect a trade-off between the benefits of acquiring food and the costs of movement. Changes in the biotic and abiotic environment associated with urbanization can alter this trade-off and modify foraging decisions. We experimentally manipulated foraging opportunities for two Anolis lizard species - the brown anole ( A. sagrei) in Florida and the crested anole ( A. cristatellus) in Puerto Rico - to assess whether foraging behavior differs between habitats varying in their degree of urbanization. In both urban and natural forest habitats, we measured the latency of perched anoles to feed from an experimental feeding tray. We manipulated perch availability and predator presence, while also taking into account population (e.g., conspecific density) and individual-level factors (e.g., body temperature) to evaluate whether and how these contribute to between-habitat differences in foraging behavior. In both species, urban anoles had longer latencies to feed and lower overall response rates compared to lizards from forests. Urban anoles were also larger (i.e., snout-vent length and mass) in both species and urban A. sagrei were in better body condition than the natural forest population. We postulate that the observed patterns in foraging behavior are driven by differences in perceived predation risk, foraging motivation, or neophobia. Although we are unable to identify the mechanism(s) driving these differences, the substantial differences in urban versus forest anole foraging behavior emphasizes the importance of understanding how urbanization influences animal populations and their persistence in anthropogenically-modified environments. [ABSTRACT FROM AUTHOR]

Novel selective pressures derived from human activities challenge the persistence of animal populations worldwide. Behavior is expected to be a major factor driving animals' responses to global change because it largely determines how animals interact with the environment. However, the role of individual variation in behavior to facilitate the persistence of animals in changing environments remains poorly understood. Here, we adopted an animal personality approach to investigate whether different behavioral traits allow animals to deal with two major components of global change: urbanization and biological invasions. By studying six populations of Anolis sagrei lizards, we found for the first time that anoles vary consistently in their behavior across different times and contexts. Importantly, these animal personalities were consistent in the wild and in captivity. We investigated whether behavioral traits are pulled in different directions by different components of global change. On the one hand, we found that lizards from urban areas differ from nearby forest lizards in that they were more tolerant of humans, less aggressive, bolder after a simulated predator attack, and they spent more time exploring new environments. Several of these risk-taking behaviors constituted a behavioral syndrome that significantly differed between urban and forest populations. On the other hand, the behavior of urban A. sagrei coexisting with the invasive predatory lizard Leiocephalus carinatus was associated with dramatic changes in their foraging niche. Overall, we provide evidence that differences in animal personalities facilitate the persistence of animals under novel selective regimes by producing adaptive behaviors relevant to their ecology such as predator avoidance. Our results suggest that natural selection can favor certain behaviors over others when animals are confronted with different ecological challenges posed by global change. Therefore, we underscore the need to incorporate behavioral ecology into the study of how animals adaptively respond to human-induced environmental changes. [ABSTRACT FROM AUTHOR]

The article discusses research on trait-mediated indirect interaction (TMII) between top predators and dominant vascular plants in U.S. salt marshes. Field observations show that marsh periwinkle Littoraria irrorata tend to graze extensive monocultures of Spartina alterniflora in the ecosystems studied. Experimental details which include the selection of a marsh area, measurement of grazer habitat use, and evaluation of longitudinal grazing scars seen on Spartina leaves are reported.