Habitats are characterized by different local environmental conditions that influence both behavior and morphology of species, which can result in habitat‐dependent phenotypic differences among ...animals living in heterogeneous environments. We studied 3 alpine populations of Eurasian red squirrels (Sciurus vulgaris), 1 living in a marginal high‐elevation habitat at the edge of the species’ altitudinal distribution, and 2 occurring in higher‐quality habitats. Here, we investigated whether squirrels living in the marginal area differed in 2 morphological parameters (body size and body mass) and/or in the expression of 4 personality traits estimated with an open field test and a mirror image stimulation test (activity, exploration, activity‐exploration, and social tendency). Furthermore, we tested whether within‐individual variance of the traits (behavioral plasticity) was higher in the edge habitat. Male squirrels in the edge habitat were smaller and weighed less than in the other study areas, while among females, size–habitat relationships were less marked. These sex‐specific patterns were explained by a strong association between body mass and reproductive success in female squirrels. Squirrels in the marginal habitat were more active, explorative, and had a more social personality than in the other habitats. However, in contrast to our predictions, behavioral plasticity was smaller in the marginal habitat, but only for the trait exploration. Our results suggest that animals choose the habitat that best fits their personality, and that habitat‐related differences in selective pressures may shape animals’ morphology.
Red squirrels in marginal high‐elevation habitat have different personality than in higher‐quality habitats. Males are smaller and weigh less in the marginal edge‐habitat than in the other forest types, but these patterns differ for females, for which high body mass enhances reproductive success. Habitat‐related selective pressures result in local adaptation of morphological and behavioral traits in this arboreal mammal.
Field-edge habitat is important for enhancing biodiversity and associated ecosystem services on farms for long term agricultural sustainability. However, there is some concern that this habitat will ...increase wildlife activity and damage to adjacent crops. Wildlife incursion into production areas may also pose food safety risks. A two-year study in walnut orchards and processing tomato fields in the Sacramento Valley, California, documented variable use of farm fields by mammalian wildlife. This depended on field-edge habitat (restored hedgerows versus conventionally managed field edges where vegetation was mostly controlled), wildlife species present, season, and crop monitored. In walnut orchards, deer mice (Peromyscus maniculatus Wagner, 1845) were found throughout the orchard, while house mice (Mus musculus Linnaeus, 1758) exclusively used hedgerows. In tomato fields, deer mice were more common in field interiors during spring, but used field-edge habitats more during summer; the opposite was true for house mice. In general, deer mice preferred more open sites, while house mice were most numerous in areas with thick cover. Both desert cottontails (Sylvilagus audubonii Baird, 1858) and black-tailed jackrabbits (Lepus californicus Gray, 1837) showed affinity to hedgerow portions of fields, although this association was stronger for cottontails. Overall, we documented greater mammalian species richness and abundance associated with hedgerows. However, this increase in diversity did not generally lead to greater wildlife incursion into adjacent crops. In walnut orchards, Salmonella and non-O157 STEC were detected from 2 (1%) and 4 (2%) individual rodents, respectively (n = 218); no detections occurred in tomato fields. A subset of fecal samples (n = 87) from rodents captured in walnut orchards were positive for Giardia (25%) and Cryptosporidium (24%) but prevalence was not associated with field-edge habitat type. Overall, there does not appear to be a substantially greater risk of crop loss or contamination of foodborne pathogens in crops bordered by hedgerows in our study in the Sacramento Valley, although potential damage could vary by the stage and type of crop and wildlife species present.
•Hedgerows were associated with greater wildlife abundance and diversity.•Hedgerows did not generally yield greater wildlife incursion into field interiors.•Hedgerows did not have any noticeable impact on foodborne pathogen prevalence.•In tested crop systems, hedgerows did not increase human-wildlife conflict concerns.
Wind power development is regarded as a clean energy source. Efforts to mitigate climate change, however,may degrade habitat and compromise wildlife. During winter 2011–2012, we examined the ...potential influence of a wind farm on a community of carnivores in the New England-Acadian Forest, northern New Hampshire, United States, with a focus on American martens (Martes americana), a mid- to late-successional forest species adapted for snow. We counted marten, red fox (Vulpes fulva), and coyote (Canis latrans) tracks and measured snowpack along roads, and snowmobile and hiking trails to determine the relative influence of wind farms on space use for each species. We observed all species at high-elevations (>823 m), although use frequency varied by road or trail type. As expected, we detectedmartens most often at high elevations along hiking trails and least often along wind farm roads. We observed the opposite pattern for red foxes and coyotes. Additionally, there was a higher probability of observing canids when snow depth increased and a lower probability when penetrability increased. Although our results indicate spatial partitioning, the edge habitat and compacted snow created by wind farm roads increased access for canids to high-elevation forest. In addition to habitat loss and fragmentation, these conditions may increase competition for martens and lower population viability. Future wind development should minimize disturbance of rare habitats, especially those considered climate refugia.
Preventing biodiversity loss in fragmented agricultural landscapes is a global problem. The persistence of biodiversity within remnant vegetation can be influenced by an animal's ability to move ...through the farmland matrix between habitat patches. Yet, many of the mechanisms driving species occurrence within these landscapes are poorly understood, particularly for reptiles.
We used scented and unscented plasticine lizard models and wildlife cameras to (a) estimate predation risk of reptiles in four farmland types (crop field, pasture paddock, restoration tree planting and areas with applied woody mulch) relative to the patch edge and remnant vegetation, and (b) examine how predation risk was influenced by temporal change in the matrix (crop harvesting).
Birds (55.1%), mammals (41.1%), reptiles (3.4%), and invertebrates (0.5%) attacked models, of which 87% were native species. Mammalian predators were 60.2% more likely to attack scented models then unscented models. Bird predators were not influenced by scent.
We found predator attacks on models were highest at edges (49%, irrespective of adjacent farmland type, with a reduced risk within farmland (29%) and remnant patches (33%) (p < 0.01). Both mammal and bird predators contributed to high numbers of predation attempts at edges.
Removal of crops did not increase predation attempts in crop fields or other farmland types, although predation attempts were significantly lower along the crop transect after harvesting, compared to the woody debris transect. However, numbers of predation attempts were higher in edge habitats, particularly prior to harvesting.
Synthesis and applications. Reptiles are at risk of predation by birds and mammals in both remnant patches and the farmland matrix, particularly in edge habitat. Our results demonstrate that edge habitats are potentially riskier for lizards than the farmland. Vulnerability to predation may be increased by a lack of shelter within edge habitats such as by increasing visibility of reptiles to predators. Therefore, to benefit reptiles, land managers could provide shelter (rocks, logs, and grasses), particularly between remnants and linear plantings which could improve landscape connectivity.
Reptiles are at risk of predation by birds and mammals in both remnant patches and the farmland matrix, particularly in edge habitat. Our results demonstrate that edge habitats are potentially riskier for lizards than the farmland. Vulnerability to predation may be increased by a lack of shelter within edge habitats such as by increasing visibility of reptiles to predators. Therefore, to benefit reptiles, land managers could provide shelter (rocks, logs, and grasses), particularly between remnants and linear plantings which could improve landscape connectivity.
Seagrass and mangrove habitats have long been established as critical for diverse species at various life-stages, particularly as nursery grounds. However, despite their intrinsic and environmental ...value, these ecosystems are increasingly threatened by anthropogenic activities. In Bimini, Bahamas, where ongoing development threatens ecosystem integrity, baited remote underwater video surveys (BRUVs) were used to examine faunal communities in both nearshore habitat and a shallow water central lagoon (average depth 1 m). The study assessed species abundances and spatial distribution in a currently unperturbed of the North Bimini Marine Reserve (NBMR).
A total of 140 BRUVs, conducted over a 13-month period, recorded 62 species from 27 different families. MaxN was used to assess relative abundances and multivariate analyses (i.e. nMDS, PCA, PERMANOVA) investigated differences in community composition across discrete factors and environmental variables. Boosted Regression Trees (BRTs) were used to explore environmental variables for their uncorrelated influences on recorded species diversity. Findings evidenced the importance of habitat diversity and particularly mangrove-adjacent habitat for teleost fishes in Bimini with species diversity and abundance being significantly greater in the mangrove-adjacentdge habitat. Further, the study highlighted differences in environmental conditions between habitat types and the association this had with species diversity, abundance and distribution. Despite the shallow water environment, BRUVs served as a scalable, non-invasive technique to assess community structures within the study site. Results from this study should inform ongoing decision-making processes regarding the protection of the Bimini Islands ecosystem.
Spatial heterogeneity in the local densities of terrestrial carnivores is driven by multiple interacting biotic and abiotic factors. Space-use patterns of large carnivores reflect the competing ...demands of resource selection (e.g., exploitation of habitats with abundant prey) and minimization of risks arising from human interactions. Estimating the relative strength of these drivers is essential to understand spatial variation in densities of large carnivores and there are still key knowledge gaps for many large carnivore populations. To better understand the relative roles of environmental and human drivers of spatial variation in tiger (Panthera tigris) densities, we surveyed a 3000 km2 landscape in North India using camera trap data. Over two years, we photo-captured 92 unique adult tigers. Associating spatial covariates with patterns of detection allowed us to test hypotheses about the relative influence of prey abundance, habitat structure and extent, and proximity to habitat edges on spatial variation in tiger densities across a gradient of anthropogenic disturbance. We documented extensive variation in tiger density within and across management units and protected areas. Spatial variation in prey abundance and proximity to grassland habitats, rather than human use (e.g. extent of human-dominated edge habitat and protection status), explained most of the spatial variation in tiger density in two of the five surveyed sites. The region’s largest tiger population occurred in a multi-use forest beyond protected area boundaries, where wild ungulates were abundant. Our results suggest that tigers can occur at high densities in areas with extensive human use, provided sufficiently high prey densities, and tracts of refuge habitats (eg. areas with dense vegetation with low human use). We argue that tiger conservation portfolio can be expanded across multi-use landscapes with a focus on areas that are adaptively managed as “zones of coexistence” and “refuge habitats”. Advancing this conservation strategy is contingent on greatly strengthening systems to effectively and equitably redress human–wildlife conflict and leveraging existing policies to strengthen local participation in conservation planning and forest stewardship. Our insights into the environmental drivers of spatial heterogeneity in tiger populations can inform both local management and guide to species recovery in working landscapes.
Wild lupine (
Lupinus perennis
) is a perennial plant originally found primarily throughout the United States and Canada in oak savannas, which are considered an ecotone between prairie and forest. ...Because of primary habitat loss, this early successional plant is declining and now persists in managed edge habitats such as power line rights-of-way and roadsides across much of its range. Many edge populations of wild lupine are small and isolated, which can hinder the reproduction of this pollinator-dependent plant. Here, we synthesize current literature about the biology and management of wild lupine and associated plants and insects. We also highlight current gaps of knowledge to guide future research on wild lupine and, more generally, on savanna-like habitats. The information provided here on lupine serves as a case study for how edge habitat conserves rare plant species reliant on disturbance. Overall, habitat characteristics that seem best for wild lupine include a gradient of canopy cover from moderate to open, well-drained soils, and a low abundance of understory woody plants. Land management, including prescribed burning, mowing, and mechanical thinning, can promote the conservation of wild lupine and other forest edge plants. However, additional research in regards to ideal management regimes and intensity is needed to further plant conservation in forest edge habitat.
Designers, builders, and managers of sustainable urban areas must consider location and proximity of conserved land, built infrastructure, and designed urban ecosystems such as stormwater ponds and ...ornamental gardens. This publication introduces four key spatial considerations and discusses their implications for conservation of native plants and animals and the biodiversity and ecological benefits provided by urban landscapes. Planners, builders, and managers must recognize and conserve spatial differences in habitat types and understand how the size, shape, and location of conserved lands and urban ecosystems affect plant and animal welfare and movement. The publication lists multiple free tools for visualizing and measuring spatial aspects and stresses that conserved areas and designed ecosystems must be properly managed to reap benefits from good spatial planning. People can use the information to improve the design, construction and management of sustainable urban areas.
Species can respond to environmental pressures through genetic and phenotypic variation. Lysimachia maritima (L.) Galasso, Banfi & Soldano, a perennial halophyte, is distributed sporadically along ...the east coast in south Korea and is designated as an endangered plant species in Korea and ‘Least Concern’ in the IUCN Red List. To understand the phenotypic and genetic variations of L. maritima among sites and the environmental factors contributing to these differences, field surveys and genetic analyses were conducted. The principal component analysis of the environmental characteristics revealed that soil type, temperature, soil moisture content, and organic matter content were major factors determining variations among sites. L. maritima in Goseong (GS) and Yangyang (YY) sites faced significant limitations in its distribution due to competition with Phragmites australis for limited soil water and nutrients. There were significant phenotypic differences of L. maritima among sites. In sand-based sites of GS and YY, studied growth characteristics of L. maritima except stem length in YY and the number of seed-bearing individuals were smaller than those in organic soil substrate sites of US and PH, where L. maritima grew vigorously and were almost exclusively in the sexual reproductive phase. Genetic diversity at species level was high (h= 0.31, I= 0.46) but genetic diversities at site level were low, varying among sites (h= 0.133 ∼ 0.244). Also, genetic variation of L. maritima was higher within sites (58.32%) than among sites (41.68%). This indicates that L. maritima might prefer outcrossing more than selfing. L. maritima were strongly differentiated among sites (Gst= 0.336) because of limited gene flow (Nm= 0.987). Geographical isolation might have led to differentiated genetic structure in L. maritima, contributing to the formation of its spatial genetic structure. This high genetic diversity is crucial for the biodiversity of L. maritima at its global distribution limit, and this study emphasize the necessity of conserving distribution limit in the sense of soil characteristics.
•Phenotype and genetic variations of Lysimachia maritima were determined in edge habitats.•Limited nutrients were related with the increase of density and sexual reproduction.•Genetic diversity was accompanied by genetic differenciation among habitats.•To conserve endangered L. maritima at edge habitats in Korea, all populations should be conserved.
Transitional zones, such as edge habitat, are key landscapes for investigating biodiversity. “Soft edges” are permeable corridors that hosts can cross, while “hard edges” are impermeable borders that ...hosts cannot pass. Although pathogen transmission in the context of edges is vital to species conservation, drivers of host-parasite relationships in ecological edges remain poorly understood. Thus, we defined a framework for testing hypotheses of host-parasite interactions in hard and soft edges by (1) characterizing hard and soft edges from both the host and parasite perspectives, (2) predicting the types of parasites that would be successful in each type of edge, and (3) applying our framework to species invasion fronts as an example of host-parasite relationships in a soft edge. Generally, we posited that parasites in soft edges are more likely to be negatively affected by habitat fragmentation than their hosts because they occupy higher trophic levels but parasite transmission would benefit from increased host connectivity. Parasites along hard edges, however, are at higher risk of local extinction due to host population perturbations with limited opportunity for parasite recolonization. We then used these characteristics to predict functional traits that would lead to parasite success along soft and hard edges. Finally, we applied our framework to invasive species fronts to highlight predictions regarding host connectivity and parasite traits in soft edges. We anticipate that our work will promote a more complete discussion of habitat connectivity using a common framework and stimulate empirical research into host-parasite relationships within ecological edges and transitional zones.
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