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Abstract Mid-sized mammals (i.e., mesomammals) fulfill important ecological roles, serving as essential scavengers, predators, pollinators, and seed dispersers in the ecosystems they inhabit. Consequently, declines in mesomammal populations have the potential to alter ecological processes and fundamentally change ecosystems. However, ecosystems characterized by high functional redundancy, where multiple species can fulfil similar ecological roles, may be less impacted by the loss of mesomammals and other vertebrates. The Greater Everglades Ecosystem in southern Florida is a historically biodiverse region that has recently been impacted by multiple anthropogenic threats, most notably the introduction of the Burmese python (Python molurus bivittatus). Since pythons became established, mesomammal populations have become greatly reduced. To assess whether these declines in mesomammals have affected two critical ecosystem functions—scavenging and frugivory—we conducted experiments in areas where mesomammals were present and absent. We did not observe significant differences in scavenging or frugivory efficiency in areas with and without mesomammals, but we did observe significant differences in the communities responsible for scavenging and frugivory. Despite the observed evidence of redundancy, the changes in community composition could potentially lead to indirect consequences on processes like seed dispersal and disease dynamics within this ecosystem, emphasizing the need for further study.

Recent advances in optical remote sensing (RS) technology in combination with lightweight Global Positioning System (GPS) tracking devices now make analyzing the multi-scale habitat selection (HS) of small mammals < 2 kg possible. However, there have been relatively few multi-scale HS studies integrating fine-scale RS data with data-rich, GPS-derived movement data from small mammals. This is critical because small mammals commonly select habitat features across multiple scales. To address this gap, we investigated the HS of a small mammal, fox squirrels (Sciurus niger), which are known to cover relatively large areas and select fine-scale environmental features. We specifically asked the following questions: (1) Do next-generation RS variables improve HS models at single spatial scales? (2) Do multi-scale HS models improve upon those at single spatial scales? Using data from 45 individuals, we constructed HS models at three spatial scales: 4 ha (210 m × 210 m), 0.09 ha (30 m × 30 m), and 0.01 ha (10 m × 10 m) using traditional and next-generation RS data. The 4-ha model, using traditional and next-generation RS data, produced the best single-scale model, explaining 58% of the variations in HS. However, the multi-scale model provided the most informative model, explaining 68% of the variations in HS. Our models provide evidence for the value of next-generation RS data when quantifying HS and additional support for the idea of studying HS at multiple spatial scales.

Abstract To understand how two dominant African savanna trees will continue to respond to climate changes, we examined their regeneration niche and adult tree distributions. Specifically, we wanted to (1) determine if distributional patterns were shifting, (2) predict future distributions under different climate change scenarios and (3) evaluate the realism of predicted future distributions. We randomly placed 40 grids into 6 strata across a climate gradient in the kingdom of Eswatini. Within these grids, we sampled adult and seedling marula (Scelerocarya birrea) and knobthorn (Senegalia nigrecens) trees and used the data to model their abundance. Next, we quantified shifts in distributional patterns (e.g., expansion or contraction) by measuring the current and projected areas of overlap between seedling and adult trees. Finally, we predicted future distributions of abundance based on predicted climate conditions. We found knobthorn seedlings within a small portion of the adult distribution, suggesting it was unlikely to track climate changes. Alternatively, finding marula seedlings on and beyond one edge of the adult distribution, suggested its range would shift toward cooler climates. Predicted future distributions suggest suitable climate for both species would transition out of savannas and into grasslands. Future projections (2041–2070) appeared consistent with observed distributions of marula, but knobthorn predictions were unrealistic given the lack of evidence for regeneration outside of its current range. The idiosyncratic responses of these species to climate change are likely to decouple these keystone structures in the coming decades and are likely to have considerable cascading effects including the potential rearrangement of faunal communities.

Climate change is altering the distribution of wildlife across the globe. These distributional changes, paired with the environmental and vegetative shifts that spurred them, are likely to change co-occurrence patterns and interspecific interactions of native and invasive wildlife. A mesocosm of global change, we worked on Sanibel Island; a low-lying ∼4,900 ha barrier island in southwestern Florida, USA. Sanibel Island possessed a freshwater interior lined with mangrove forests to the north. Sanibel was ∼50% developed, ∼50% conserved, hydrologically degraded, shrub-encroached, and susceptible to inundation by sea-level rise. We used a Bayesian multispecies occupancy modeling approach to investigate how the effects of climate change might change co-occurrence patterns of 2 native island-endemic species (Sanibel Island rice rat [Oryzomys palustris sanibeli]; insular hispid cotton rat [Sigmodon hispidus insulicola]) and 1 exotic invasive species (black rat [Rattus rattus]). We found that co-occurrence is likely to increase between cotton rats and black rats with unknown impacts on interspecific interactions. We also found that climate change may threaten the persistence of cotton rats and black rats on Sanibel Island, but not rice rats so long as mangrove forests persist. Broadly our research demonstrates the importance of investigating interactions between climate change and co-occurrence when assessing contemporary and future wildlife distributions.

Our understanding of synchrony between populations from different taxonomic groups has been centered on predator–prey dynamics in simple systems but has rarely been examined in complex predator–prey systems. In addition to trophic interactions such as predator–prey dynamics, there is some evidence that exogenous factor such as climatic variation may facilitate synchrony between different taxonomic groups. Using three longitudinal datasets on quail (Colinus virginianus) and cotton rats (Sigmodon hispidus) we examined 1) the consistency of synchrony across time and space, 2) the relative influence of trophic interactions vs. exogenous factors on synchrony and 3) if trophic interactions were positively associated with synchrony between populations. We found evidence of consistent synchrony in cotton rat and bobwhite populations at both the site and regional levels. We found that trophic interactions between cotton rats and bobwhite were associated with relative synchrony between these populations, but these interactions appeared to weaken in years of greater synchrony. We did not find evidence that exogenous factors influenced relative synchrony at the regional level. Given the lack of a clear mechanistic explanation of the patterns observed in our data, we propose an alternative climate-mediated predation framework to explain synchrony in complex predator–prey systems. This framework includes both classic bottom-up theories of regulation while integrating trophic interactions via components of the shared predator hypothesis.

Burkett-Cadena et al. use a combination of field survey methods, citizen science data, and molecular analysis to determine how the invasive Burmese python distribution affects mammal host use and virus infection by vector mosquitoes. This study shows how python predation has shifted vector host use towards virus-amplifying rodents, increasing virus infection rates, and illustrates the indirect effects an invasive species has on the disease ecology of wildlife and public health.

Infectious diseases vary in prevalence and pathology among host species. Species may differ in prevalence of infection due to varying exposure and susceptibility to disease agents throughout their lifetime, which may be attributable to underlying differences in their phenology, physiology and behavior. A recently growing body of literature has focused on the utility of host life-history traits to provide mechanistic explanations for interspecific variation in host-parasite associations. In this study, we utilized diverse avian and haemosporidian assemblages in an African savanna to evaluate the link between haemosporidia prevalence (Plasmodium, Haemoproteus, Leucocytozoon) and avian life-history traits such as body size, mating system, nest care and nest structure. We found that variation of haemosporidia prevalence was consistent with life-history traits that pertain to the reproduction of avian host. Nest care was the single most important predictor of infection status. In birds with shared and female-only nest care, the expected rates of parasitism were between 8- and 12-fold higher than in avian brood parasites that provide no nest care. This finding supports the hypothesis that parental care is an evolutionarily costly life-history trait that increases species' risk of infection with vector-borne diseases. The influence of other host traits (nest structure, body size) was less consistent suggesting that differences in the vectors’ ecology and host-seeking behavior produce variable patterns of parasitism among haemosporidia genera. Nest structure influenced infection with Haemoproteus and Leucocytozoon only. Leucocytozoon infections were associated with ground-nesting birds, while Haemoproteus infections were associated with birds that build open nest structures. Body size was an important predictor of Leucocytozoon infections, particularly large-bodied birds like guineafowl and doves, which exhibited high prevalences.

Increasing human–bear conflicts are a growing concern, and managers often assume bears in developed areas are food-conditioned. We examined the relationship between human–bear conflicts and food conditioning by analyzing isotopic values of hair from black bears (Ursus americanus floridanus) involved in research (n = 34) and conflicts (n = 45). We separated research bears into wild and developed subgroups based on the impervious surface within their home ranges and separated conflict bears based on observations of human food consumption (anthropogenic = observations; management = no observations). We initially assumed wild bears were not food conditioned and anthropogenic bears were. However, using isotopic values, we classified 79% of anthropogenic bears and 8% of wild bears as food conditioned. Next, we assigned these bears to the appropriate food conditioned category and used the categorizations as a training set to classify developed and management bears. We estimated that 53% of management bears and 20% of developed bears were food conditioned. Only 60% of bears captured within or using developed areas showed evidence of food conditioning. We also found that δ13C values were a better predictor of anthropogenic foods in a bear’s diet than δ15N values. Our results indicate that bears in developed areas are not necessarily food conditioned and caution against management actions based on limited observations of bear behavior.

Agricultural intensification is a threat to terrestrial ecosystems around the world. Agricultural areas, especially monocultures, create homogenous landscapes for wildlife. However, certain crops, such as sugarcane, are harvested in phases, creating a mosaic of fields in different stages of growth. We investigated changes in avian communities across four different sugarcane growth stages: emerging, short, medium and tall sugarcane, as well as control sites that represented native savanna habitat in northeast Eswatini prior to conversion to agriculture. In total, we sampled nine sites in sugarcane fields (at different growth stages) and three in native savanna. We conducted bird counts at 5-week intervals along 200m line transects over both the breeding and non-breeding seasons. We recorded a total of 124 bird species belonging to 58 families. Bird species richness and diversity were higher in savannas compared to any stages of growth in sugarcane. In contrast, functional beta diversity and uniqueness were higher in sugarcane than in savanna. Community composition was also different between the two land-uses. While there was overlap in bird species composition between different sugarcane growth stages, there was high beta diversity and high turnover between sites, indicative of the high temporal and spatial variability in bird communities in sugarcane fields. We demonstrated that the spatial and temporal variability created by the different growth stages of sugarcane promotes the occurrence of species with different traits, which may contribute to ecosystem functioning and promote the conservation of bird species as sugarcane fields can provide resource complementation for species with different needs.

Human activities are changing the environments that animal communities utilize, altering competition and co-existence dynamics as well as changing species distributions. A global consequence of human activity is increased woody cover, which changes environmental conditions on landscape, local, and fine spatial scales. These multi-scale processes are likely to change species interactions and distributions in unexpected ways. To elucidate these effects, we investigated the co-occurrence of two interacting species in a rapidly changing ecosystem. Eastern fox (Sciurus niger) and gray (Sciurus carolinensis) squirrels occur sympatrically throughout the southeastern United States. We used single-season, two-species occupancy modeling to understand what factors influence competition between the squirrels at three spatial scales. We found evidence that fox and gray squirrels compete at fine scales but not at local and landscape scales. The best model to explain fox and gray squirrel co-occurrence at fine scales was an additive fine-scale understory and tree canopy closure model. Increased fine-scale canopy closure correlated with increased fox and gray squirrel occupancy, while increased fine-scale understory cover correlated with decreased gray and fox squirrel occupancy. Fox squirrel occupancy probability declined in the presence of gray squirrels. The intensity of interaction was modified by fine-scale canopy cover and understory density. These findings support the hypothesis that species interactions can be an important factor in structuring biotic communities; however, the strength of the effect changes across spatial scales. Our results support the importance of considering species interactions at multiple scales when predicting and addressing changes in community composition in human modified and managed systems.

ABSTRACT Live‐trapping is important for studying wildlife. In 2016 at Ordway‐Swisher Biological Station in Melrose, Florida, USA, we tested the efficacy of a modified pitfall trap designed to safely and effectively capture southeastern pocket gophers (Geomys pinetis). When compared with the commonly used Hart trap, the new design captured 92% of all live captures of southeastern pocket gophers. The novel trap has a simple, passive design that eliminates dependence on trigger mechanisms, allows for safe overnight trapping, and reduces on‐site hours by researchers. The new trap adds to the few live traps available to study ecologically important and understudied fossorial species. © 2019 The Wildlife Society.

The color patterns of an animal’s pelage, feather, or skin serve a variety of adaptive functions; importantly, one function is concealment through background matching. In spatially and temporally heterogeneous environments, some species exhibit multiple distinct color patterns within a population (i.e., color polymorphism). The environmental drivers of color polymorphism are poorly understood. We used the polymorphic eastern fox squirrel (Sciurus niger ssp.; hereafter, fox squirrel) as a model species to investigate the role of environmental factors on pelage coloration. Building upon previous research that investigated the drivers of melanism, we measured fox squirrel pelage coloration across the visible light spectrum. Agouti-colored squirrels were positively associated with increased proportion of burned area in a fox squirrel dispersal buffer. Light-colored (less melanistic) squirrels were positively associated with increasing proportion of cropland in a fox squirrel dispersal buffer. We posit that agouti pelage is broadly adapted to a range of heterogeneous conditions created by fire. Conversely, croplands, once established, are relatively stable ecosystems which promote a consistently adaptive light-colored pelage morph. We suggest that in an increasingly human-dominated environment, spatially and temporally homogeneous processes, such as prescribed burning, may not sufficiently recreate environmental heterogeneity, which could result in lost pelage diversity.

ABSTRACT Mist nets are commonly used to capture free‐flying bats; however, some bat species are very difficult to capture because of their flight behavior, habitat preferences, and ability to avoid nets. High‐flying, open‐space foragers are especially underrepresented by mist‐net surveys. Few studies have investigated the effectiveness of using acoustic lures (playbacks of conspecific vocalizations) to increase capture success of bats in mist nets. We tested the efficacy of an acoustic lure to capture a high‐flying rare molossid, the endangered Florida bonneted bat (Eumops floridanus), which had been captured only once away from a known roost prior to our research. We used a crossover experimental design with 2 lure treatments (nets with lures playing social call recordings from 2 different roosts) and 2 control nets (no lures) in 6 sites for 2 nights each. We captured 15 Florida bonneted bats in our treatment nets and 0 in our control nets. One lure had greater capture success (n = 13) than the other (n = 2), with a trend for greater captures of males (n = 11) than females (n = 4). We suggest that these differences were due to the social context in which the calls used in the lures were recorded. Our study demonstrated the utility of acoustic lures to capture Florida bonneted bats and expands research opportunities critical to the species’ conservation, such as the ability to use radio telemetry to track captured bats to unknown roosting and foraging areas. Our study also lays the foundation for future research into social call playbacks as a technique to lure other high‐flying and elusive bat species into mist nets. © 2017 The Wildlife Society.

Conversion of native habitats into agricultural monocultures is a major cause of biodiversity loss favouring a small number of generalist species. Rodents can cause significant declines in crop yield, hence understanding the factors affecting their population dynamics is of importance to the agricultural sector. Sugarcane plantations in African savannas harbour a low diversity of small mammals, with a single genus (Mastomys spp.) often dominating the community. Our study investigated the factors that shape the composition of the small mammal community and the life-history traits of the dominant species in a savanna-sugarcane landscape mosaic. We surveyed small mammals at eight sites, six in sugarcane and two in neighbouring savannas at five-week intervals over the course of a year. Sugarcane and native savanna sites were categorised into vegetation height classes. We captured a total of 845 individual small mammals belonging to eight species across all sites. Species diversity was higher in the savanna than in sugarcane fields. Although the composition of the community overlapped in the two habitats, it was most similar between tall sugarcane and savanna, than between sites that had recently planted (emerging or short) sugarcane and either tall sugarcane or savanna. Furthermore, population densities of the dominant species (Mastomys natalensis) were significantly higher in sugarcane than in native savanna. Additionally, the interactions between habitat and season influenced survival and body condition of M. natalensis; apparent survival decreased in savanna and body condition improved in sugarcane during the wet season. Furthermore, the survival of M. natalensis was also significantly reduced in sugarcane fields that had been burnt prior to harvesting. However, there was no significant difference in the extent of breeding between the two habitats. This study provides novel insight into the mechanisms that allow for the persistence of high densities of rodent pest species. Keywords: Small mammals, Crop pests, Agriculture, Sugarcane, Population dynamics, Community structure

ABSTRACT Fox squirrels (Sciurus niger) in the southeastern United States have been difficult to survey because of their sparse distribution, large home ranges, and low capture success. Remote cameras have proven to be an effective tool for surveying larger mammals, including identifying individual animals using their unique markings. To test whether cameras can be used to identify individual fox squirrels in the southeastern United States, we 1) inspected digital photographs of fox squirrels; 2) identified variable pelage features for individual identification; 3) tested the ability of wildlife students and professionals to identify individuals; and 4) evaluated whether training improved participants' ability to identify individuals. We found that fox squirrels could be individually identified using a combination of sex and 10 variable pelage features, including the color morph, presence of an eye ring, distribution of white on the rostrum, and facial markings. In total, we developed ≥25,920 possible combinations of features to identify southeastern fox squirrels. We found survey participants were capable of identifying fox squirrels without training, but their average ability to do so increased significantly from 73.6% to 80.3% after training (t[df = 106] = 5.068, P

Due to increasing threats facing bats, long-term monitoring protocols are needed to inform conservation strategies. Effective monitoring should be easily repeatable while capturing spatio-temporal variation. Mobile acoustic driving transect surveys (‘mobile transects’) have been touted as a robust, cost-effective method to monitor bats; however, it is not clear how well mobile transects represent dynamic bat communities, especially when used as the sole survey approach. To assist biologists who must select a single survey method due to resource limitations, we assessed the effectiveness of three acoustic survey methods at detecting species richness in a vast protected area (Everglades National Park): (1) mobile transects, (2) stationary surveys that were strategically located by sources of open water and (3) stationary surveys that were replicated spatially across the landscape. We found that mobile transects underrepresented bat species richness compared to stationary surveys across all major vegetation communities and in two distinct seasons (dry/cool and wet/warm). Most critically, mobile transects failed to detect three rare bat species, one of which is federally endangered. Spatially replicated stationary surveys did not estimate higher species richness than strategically located stationary surveys, but increased the rate at which species were detected in one vegetation community. The survey strategy that detected maximum species richness and the highest mean nightly species richness with minimal effort was a strategically located stationary detector in each of two major vegetation communities during the wet/warm season.

ABSTRACT Camera traps have increased our knowledge of animal distribution, activity, and behavior, but they are rarely used for small mammal research. This is likely because there are few techniques to that allow for species identification, reduce disturbance of bait from non‐target animals (e.g., raccoon [Procyon lotor]), and that can be used in all environments. In this paper we present a small mammal camera‐trapping methodology, the Hunt trap, which was designed to 1) work in tidal environments, 2) eliminate capture myopathy, 3) allow for successful identification of small mammal species, and 4) allow for continued trapping after disturbance by non‐target species. We tested the Hunt trap in the Lower Suwannee National Wildlife Refuge, Florida, USA, during February 2012 to February 2013. Live traps are still the best option when individuals must be physically captured for marking, radiotagging, demographic studies, or physiological assessments. However, if such data are not required, the Hunt trap design is an excellent technique to monitor species diversity, community composition, habitat selection, and distribution with efficiency and minimal effort. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

People are increasingly affected by climate change. In response, some people adapt, but others may not. The aim of our research was to understand what factors influence successful adaptation to climate change in context. We surveyed rural small-scale farmers in Eswatini who had recently experienced a severe drought, and collected data on adaptive capacity, measured as household access to five types of capital: natural (access to and use of natural resources), social (integration within local social networks), financial (income and wealth), physical (access to assets and infrastructure), and human (education and employment). Our goals were to identify which type of capital was most important in driving adaptation and to identify the specific ways in which capital supported adaptation. We found that social capital and natural capital increased successful drought adaptation more than other types of capital. Primarily, social and natural capital increased access to other resources and opportunities that enabled adaptation. Our research highlights the complex pathways along which capital operates to support adaptation, and furthers our understanding of in-situ adaptation experiences.

We assessed the effects of red imported fire ants (Solenopsis invicta; hereafter fire ant) on the foraging of hispid cotton rats (Sigmodon hispidus). We used a manipulative experiment, placing resource patches with a known amount of millet seed within areas with reduced (RIFA [-]) or ambient (RIFA [+]) numbers of fire ants. We measured giving up densities (the amount of food left within each patch) within the resource patches for 4 days to quantify the effects of fire ants on cotton rat foraging. We assessed the effects of fire ant treatment (RIFA), Day, and their interaction on cotton rat giving up densities. Giving up densities on RIFA [+] grids were nearly 2.2 times greater across all foraging days and ranged from 1.6 to 2.3 times greater from day 1 to day 4 than the RIFA [-] grids. From day 1 to day 4, mean giving up densities decreased significantly faster for the RIFA [-] than RIFA [+] treatments, 58% and 13%, respectively. Our results demonstrate that cotton rats perceive a risk of injury from fire ants, which is likely caused by interference competition, rather than direct predation. Envenomation from ants likely decrease the foraging efficiency of cotton rats resulting in more time spent foraging. Increased time spent foraging is likely stressful in terms of the opportunity for direct injury and encounters with other predators. These indirect effects may reduce an individual cotton rat's fitness and translate into lowered population abundances.

There has been a growing recognition that the narrow linear strips of uncultivated vegetation that lie between roads and agricultural crops, referred to as roadside right-of-ways or verges, can serve as areas for the conservation of wildlife. The features of right-of-ways that should influence the composition of wildlife communities vary considerably. Our goal was to determine what features of right-of-ways increased the conservation potential of right-of-ways for wildlife in a grassland system dominated by agricultural production. We sampled 100 right-of-ways for birds and 92 right-of-ways for small mammals in McDonough and Warren Counties in west-central Illinois. We found that the sizes of right-of-ways and the amount of traffic on the adjacent roads synergistically worked to influence wildlife communities. On roads with low traffic, avian species richness increased rapidly with increased right-of-way width, while on roads with high traffic, avian richness increased only slightly with increasing right-of-way widths. We found that wider roadside right-of-ways (preferably across the road from equally wide right-of-ways) with thicker and taller vegetation had the greatest conservation value for birds and small mammals. The features that enhanced the conservation value of right-of-ways in our study area were uncommon. Efforts to create or enhance these features for the benefit of wildlife would likely face numerous obstacles. Nonetheless, from a grassland conservation perspective, working with stakeholders to implement specific strategies to enhance these often neglected areas may be an effective complement to purchasing and restoring conservation lands away from roads.

Across the planet, high-intensity farming has transformed native vegetation into monocultures, decreasing biodiversity on a landscape scale. Yet landscape-scale changes to biodiversity and community structure often emerge from processes operating at local scales. One common process that can explain changes in biodiversity and community structure is the creation of abrupt habitat edges, which, in turn, generate edge effects. Such effects, while incredibly common, can be highly variable across space and time; however, we currently lack a general analytical framework that can adequately capture such spatio-temporal variability. We extend previous approaches for estimating edge effects to a non-linear mixed modeling framework that captures such spatio-temporal heterogeneity and apply it to understand how agricultural land-uses alter wildlife communities. We trapped small mammals along a conservation-agriculture land-use interface extending 375 m into sugarcane plantations and conservation land-uses at three sites during dry and wet seasons in Swaziland, Africa. Sugarcane plantations had significant reductions in species richness and heterogeneity, and showed an increase in community similarity, suggesting a more homogenized small mammal community. Furthermore, our modeling framework identified strong variation in edge effects on communities across sites and seasons. Using small mammals as an indicator, intensive agricultural practices appear to create high-density communities of generalist species while isolating interior species in less than 225 m. These results illustrate how agricultural land-use can reduce diversity across the landscape and that effects can be masked or magnified, depending on local conditions. Taken together, our results emphasize the need to create or retain natural habitat features in agricultural mosaics.