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Animal body size often varies systematically along latitudinal gradients, where individuals are either larger or smaller with varying season length. This study examines ecotypic responses by the generalist grasshopper Melanoplus femurrubrum (Orthoptera: Acrididae) in body size and covarying, physiologically based life history traits along a latitudinal gradient with respect to seasonality and energetics. The latitudinal compensation hypothesis predicts that smaller body size occurs in colder sites when populations must compensate for time constraints due to short seasons. Shorter season length requires faster developmental and growth rates to complete life cycles in one season. Using a common garden experimental design under laboratory conditions, we examined how grasshopper body size, consumption, developmental time, growth rate and metabolism varied among populations collected along an extended latitudinal gradient. When reared at the same temperature in the lab, individuals from northern populations were smaller, developed more rapidly, and showed higher growth rates, as expected for adaptations to shorter and generally cooler growing seasons. Temperature-dependent, whole organism metabolic rate scaled positively with body size and was lower at northern sites, but mass-specific standard metabolic rate did not differ among sites. Total food consumption varied positively with body size, but northern populations exhibited a higher mass-specific consumption rate. Overall, compensatory life history responses corresponded with key predictions of the latitudinal compensation hypothesis in response to season length. [ABSTRACT FROM AUTHOR]

Urban environments impose novel challenges on animals and, as a result, the behaviors of urban wildlife are changing. In particular, high exploratory tendencies and an ability to gather more information from the environment may facilitate adoption of novel ecological opportunities. As of yet, very few studies have examined if urbanization predicts the way in which animals explore novel environments, or the extent of among-individual variation within these habitats. Here, we assess exploration and its temporal plasticity in black-capped chickadees (Poecile atricapillus ; N = 169 individuals, 14 sites) caught along an urban gradient to examine individual differences in exploration and changes in exploration over time and assays under a reaction-norm framework. As predicted, urban birds were significantly faster explorers in a novel environment (contacted more features and moved more), however urbanization did not predict individual differences in the change in exploration over time. Exploration score was moderately repeatable; interestingly, urban chickadees were more repeatable in their initial exploration behaviors, but seemed less repeatable in how they explored over time between assays in comparison to forest birds. Our results support the importance of high exploratory tendencies for urban animals, and suggest, for the first time, that individuals from urban and non-urban habitats differ in the amount of among-individual variation in exploration, and thus urban individuals may benefit from diverging more from one another in their behavior. Future work should examine the extent to which this variation in exploration and plasticity of exploration behaviors represent differences in how individuals gather information from their environment. [ABSTRACT FROM AUTHOR]

Fire metrics such as fire front location and rate of spread (ROS) are critical to understanding the behavior of prescribed fires and wildfires. This paper proposes a new method for prescribed grass fire evolution mapping and ROS measurement using multitemporal thermal orthomosaics collected by a small fixed-wing Unmanned Aircraft System (UAS) at low altitudes. The proposed method provides a low-cost, safe, and effective solution for active grass fire monitoring and fire metric measurement in areas that may be challenging for a typical rotor-wing UAS to cover due to endurance and size constraints. The proposed method is demonstrated using a prescribed grass fire data set collected by the KHawk fixed-wing UAS over a 13 ha. Kansas tallgrass prairie field on 8 October 2019. Repeat-pass thermal images collected by the KHawk UAS during about 10 min of the burning were grouped and processed to produce multitemporal orthomosaics with a spatial resolution of about 0 ˜.23 m and a horizontal position error of about 1.5 m. The resulting orthomosaics were further processed for fire front extraction and the measurement of fire front location and ROS. The head fire ROS of this grass burn was observed to be between 0.2 and 0.4 m s − 1 with a mean value of 0.27 m s − 1 . [ABSTRACT FROM AUTHOR]

ABSTRACT The sustainability of ecosystem services depends on a firm understanding of both how organisms provide these services to humans and how these organisms will be altered with a changing climate. Unquestionably a dominant feature of most ecosystems, invertebrates affect many ecosystem services and are also highly responsive to climate change. However, there is still a basic lack of understanding of the direct and indirect paths by which invertebrates influence ecosystem services, as well as how climate change will affect those ecosystem services by altering invertebrate populations. This indicates a lack of communication and collaboration among scientists researching ecosystem services and climate change effects on invertebrates, and land managers and researchers from other disciplines, which becomes obvious when systematically reviewing the literature relevant to invertebrates, ecosystem services, and climate change. To address this issue, we review how invertebrates respond to climate change. We then review how invertebrates both positively and negatively influence ecosystem services. Lastly, we provide some critical future directions for research needs, and suggest ways in which managers, scientists and other researchers may collaborate to tackle the complex issue of sustaining invertebrate-mediated services under a changing climate. [ABSTRACT FROM AUTHOR]