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• First study to assess habitat quality of oil palm for migratory birds in Mexico. • Oil palm plantations provide poorer quality habitat than forest patches. • Pressing need to develop bird friendly management strategies in oil palm. Habitat loss and degradation represent a major threat to Nearctic-neotropical migratory birds in the tropics. Managed agroecosystems have the potential to mitigate some impacts of land conversion, however, we know little regarding the quality of expanding oil palm plantation habitat for migratory birds in the neotropics. In this study, we used sex and age ratios, body condition, fat deposition, and muscle mass to assess oil palm habitat quality for seven species of migratory songbirds. Specifically, we captured individuals in native forest fragments and oil palm plantations in the state of Tabasco, Mexico, during two winter seasons (2017–2018, 2018–2019), and compared differences in age and sex ratios, and condition indices between habitats. We found that, when differences occurred, most species exhibited indicators of better habitat quality in native forest (older males with higher body condition indices) when compared to oil palm. Our results suggest that age and sex ratios combined with measures of physiological condition can be used to assess habitat quality for Nearctic-neotropical migratory birds overwintering in modified landscapes. Importantly, determining a species' territorial behavior is key when selecting a given indicator of habitat quality for each species, and in certain cases, more intensive approaches such as estimates of survival, territory size, and food availability may be needed. Our results suggest that management strategies that promote forest-like conditions in oil palm plantations will improve habitat quality for declining populations of Nearctic-neotropical migratory birds. [ABSTRACT FROM AUTHOR]

Highlights: [•] High male pairing success indicated high nesting activity in young aspen forests. [•] Most male Golden-winged Warblers were unpaired in clearcuts (no legacy tree retention). [•] Male density was an excellent indicator of pairing success. [•] High male densities were achieved by retaining hardwood trees ⩾16cm in diameter. [ABSTRACT FROM AUTHOR]

Abstract: Forest fragmentation is a common disturbance affecting biological diversity, yet the impacts of fragmentation on many forest processes remain poorly understood. Forest restoration is likely to be more successful when it proceeds with an understanding of how native and exotic vertebrates utilize forest patches of different size. We used a system of forest fragments isolated by volcanic activity 153years ago in Hawaii to examine how long-term fragmentation, as well as fragment size and structural features affect the richness of native and exotic bird species. The total number of bird species increased rapidly with forest fragment size, with most of the native species pool found in patches <3ha. Smaller fragments were dominated by native bird species with several exotic bird species found only in the largest fragments, suggesting that exotic bird species in this landscape show greater area-sensitivity than native species. We used airborne scanning light detection and ranging (LiDAR) to assess whether fragment area was correlated with estimates of fragment vegetation volume as well as measures of tree height. Fragment area was highly correlated with vegetation volume, maximum tree height, and canopy height heterogeneity, and these variables were strong predictors of bird richness, demonstrating that remote sensing can provide key insights into the relationship between fragment structural attributes and biodiversity indicators. Overall, this work demonstrates the value of conserving small remnant mid-elevation forest patches for native birds in Hawaii. This work also provides insight into how newly created forest patches might be used by native and exotic bird species in Hawaii. [Copyright &y& Elsevier]

Abstract: We investigated the potential for cross-habitat interactions to modulate per capita ungulate browse effects on forest herbaceous layers. Specifically, we examined how white-tailed deer (Odocoileus virginianus) abundance, reserve size, and landscape context at variable spatial scales interact to influence the impact of deer herbivory on forest understory communities in 16 Indiana state parks. We used native herb cover (NHC) as a proxy for deer impact to forest understories, and deer killed per unit hunter effort (DAI) as a proxy for deer abundance. Comparison of multiple regression models, using Akaike’s Information Criterion, suggested that the per capita impact of deer herbivory to forest understories was strongly related to landscape configuration of deer habitat types at the scale of an individual deer’s home range, whereas deer abundance was more strongly associated with landscape structure at broader spatial scales. Interspersion and juxtaposition of non-forested, perennial forage habitat with other habitat types (forest and agriculture) at the park plus a 0.5km buffer scale, together with DAI, explained 84% of the variation in native herbaceous cover (NHC). A model with DAI alone as a predictor accounted for only 19% of the variation in NHC. Thus, although deer impact was related to deer abundance, habitat configuration in landscapes surrounding parks appeared to strongly modulate the level of impact associated with a particular abundance of deer. Our results underscore the importance of landscape context in determining foraging behavior and per capita impacts of ungulates on forest resources in protected areas. [Copyright &y& Elsevier]

Landscapes dominated by conventional agriculture reduce and simplify natural habitats, with negative consequences for ecosystem regulating services. We examined differences in structure and composition of bee communities across biotic and abiotic gradients to investigate how these communities respond to land-use changes associated with agriculture. Studies like ours which evaluates the relative effect of different components of spatial heterogeneity remain uncommon and are important to conserve pollinator fauna. The diversity of floral resources and habitat richness including the configuration and composition of landscape heterogeneity have been shown to influence the diversity of wild bees on a landscape scale. In this study, we examined how wild bee communities respond to landscape heterogeneity in a semi-arid productive region of Entre Ríos Argentina. We modeled the effect of landscape heterogeneity on wild bee community abundance, species richness, and Chao-1 diversity. We sampled bees using pan traps in four common land-uses in the region (forest plantations, pasture/croplands, mixed use areas and native espinal savanna) for five months in the spring-summer of 2014–2015. We identified 96 bee species among 3407 bees collected in the four habitat types. Pasture/croplands along with native espinal savanna supported the highest abundance, richness, and diversity of bees. Species composition of wild bee communities differed between land uses, with numerous species unique to each land use. Across all land use types, diversity of flower resources consistently supported more abundant and diverse wild bee communities. The richness of habitats along with the diversity of floral resources acted synergistically over wild bee communities. Our findings further clarify the relationship between land-use and wild bee communities, which provide valuable pollination services to crops and native plants. Continued expansion of large-scale monoculture forest plantations will likely come at the expense of the native floral resources, which are a key component to support regional bee species richness. Promoting landscapes with a diversity of crops and flower resources are important for the conservation of pollinators that are key for the functioning of ecosystems. • Habitat richness and diversity of floral resources increases diversity of wild bees. • Habitat richness along with the diversity of floral resources acted synergistically. • Specialized bee taxa have the natural native areas as their niche. • Forest plantations are poor quality habitat for wild bee communities. [ABSTRACT FROM AUTHOR]