We asked whether the Canada lynx (Lynx canadensis) and the bobcat (Lynx rufus) differ in the internal structure of their occupied climatic niches and whether any difference translates into contrasting mid-century projections across North America. We calibrated ensemble species distribution models on 6,721 Canada lynx and 9,030 bobcat records with six climatic predictors per species, compared them in environmental space, and projected suitability to 2041–2060 under two Shared Socioeconomic Pathways and three global climate models. The two species occupy divergent observed climatic niches, and the difference is not explained by the climates available to each. The models are dominated by different climatic axes rather than by different positions along a shared one: isothermality for the Canada lynx and cold-quarter potential evapotranspiration for the bobcat. They also differ in breadth, with three biomes holding almost all Canada lynx records, compared with seven for the bobcat. Both occupied niches extend to the edge of the climate available in North America, indicating that the broader climatic tolerance of either species may not be fully resolved from this continent alone. Projections diverge: suitable climate for the Canada lynx contracts, with losses concentrated in the alpine and subalpine homologs of its lowland core. Under the design we report, bobcat suitability expands into boreal biomes it currently barely occupies, and the area suitable for both more than doubles. Because projections depend on where background data are drawn, we repeated the workflow under four pseudo-absence schemes: the direction of change held for the Canada lynx but reversed for the bobcat, and we report both.
Calcareous grassland habitat is a high-value hotspot of flowering plant and pollinator diversity, which has been lost and fragmented by historic land-use changes in Europe. Atmospheric nitrogen (N) deposition impacts terrestrial vegetation via acidification and eutrophication, potentially impacting floral resources in calcareous grasslands for pollinators. Pollinators face multiple threats linked to their declines, but the effect of anthropogenic N-deposition on pollinator communities via changes to floral resources remains to be established. We studied the impact of atmospheric N-deposition on the composition, species richness and abundance of nectar-producing plants and flower visiting insects in 130 grassland sites across seven European regions. As a measure of site-specific atmospheric N- deposition, we used nitrogen concentration of moss biomass sampled in situ validated against modelled estimates of an N-deposition gradient (EMEP). Elevated N-deposition shifted nectar provisioning in the plant community towards nitrophilic and basophilic plant taxa. Nectar availability slightly increased under higher N-deposition, mainly driven by an increased presence of Caprifoliaceae. Whereas flower visitor species richness was largely unaffected, higher N-deposition led to higher wild bee abundance and a more thermophilic assemblages of wild solitary bees. Increased nectar availability was positively associated with greater abundance of all flower visitor taxa and greater mean body size of bee communities. Flower-visitor communities were not adversely affected by N-deposition, probably due to high buffering capacity and low nutrient availability making calcareous soils currently robust against acidification and eutrophication effects. These grassland patches offer floral resources to habitat specialist and generalist flower-visiting insects species foraging in anthropic landscapes.
Full life-cycle approaches are essential for conserving long-distance migratory shorebirds, yet some life-cycle stages remain poorly understood. In Red Knots (Calidris canutus rufa), conservation efforts have focused primarily on breeding, migratory, and nonbreeding areas used by adults following the typical annual cycle, whereas oversummering areas –used mainly by individuals that defer reproduction– have received little attention. We investigated diet composition, prey availability, prey selection, and foraging performance of oversummering Red Knots from the Tierra del Fuego population on sandy beaches of the Pampas region, Argentina. Red Knots fed almost exclusively on bivalves (Donax hanleyanus and Amarilladesma mactroides), which also dominated the benthic assemblage. They selected intermediate-sized bivalves and avoided larger ones, consistent with constraints associated with handling time, shell burden, and whole-prey ingestion. Capture rates decreased with increasing conspecific density, suggesting interference competition, whereas intake rates declined with time since arrival, potentially reflecting changes in prey availability, digestive constraints or energetic requirements. These results indicate that oversummering birds rely on bivalve prey in a region where benthic communities have undergone marked historical reconfiguration, including the decline of formerly dominant A. mactroides and expansion of D. hanleyanus. Although our data do not demonstrate a causal link between prey-community change and Red Knot population trends, they reveal a previously overlooked trophic context that may constrain individuals during oversummering. Incorporating oversummering habitats and their prey resources into monitoring and recovery planning may help ensure that conservation strategies for the declining Tierra del Fuego population address constraints beyond the annual cycle of breeding adults.
Beyond species loss, redundancy and functional vulnerability are emerging properties that can serve as early warnings of ecosystem fragility based on the functional traits of species. In central-western Mexico, temperate and seasonally dry tropical forests create a complex mosaic of ecosystems, allowing for the dynamics of resource specialization that control the number of coexisting species through their functional traits. This study assessed the spatial variation of the functional traits of vertebrates in the Sierra de Quila Protected Area using a functional entity (FE) approach, where functional vulnerability was compared across five temperate and tropical vegetation types. We recorded 221 species distributed among 70 FEs, with over one-third (37
Sacred natural sites, while not always formally recognised as protected areas, can protect biodiversity via the customs and practices that prohibit exploitation for spiritual reasons. As such, these sites may align with the concept of other effective area-based conservation measures (OECMs), which recognise places that protect biodiversity outside formal protected areas. Sacred forests and groves are one type of sacred natural site that have had their biodiversity outcomes studied, providing evidence with which to assess their potential to be OECMs. Here, we reviewed studies that measured biodiversity in sacred forests, and asked whether sites could meet the criteria to be OECMs by providing positive and sustained outcomes for biodiversity, along with the management and governance structures required for sites to be OECMs. Most studies pointed to sacred forests containing important biodiversity, with over half reporting they supported intact native ecosystems. Where an impact evaluation framework was used to assess sacred forests relative to other land uses, the type of counterfactual used to assess biodiversity outcomes was important, with poorer performance reported when sacred forests were compared to protected areas. Outcomes were also poorer if monitored over time rather than at a single time point. Sites were subject to a range of anthropogenic pressures but had a range of restrictions in place to mitigate those pressures. Overall, we found that sacred forests could align well with the concept of OECMs but may need support to ensure they can maintain positive outcomes over time, especially if threats increase outside these sites.
