Montane Areas Research Articles

Impact of land use and climate changes on expansion of woody species on subalpine meadows in the Eastern Carpathians

In the 20th century, woody species expanded on many mountain ridges as grazing and mowing of subalpine grasslands was abandoned. As a result, subalpine meadows started disappearing, affecting entire montane ecosystems. To predict the consequences of changes in land use it is important to identify the ecological mechanisms behind changes in vegetation. This study examined the temporal and spatial variability of woody species succession on abandoned subalpine meadows in the Western Bieszczady Mts. (Eastern Carpathian Biosphere Reserve). We analysed the spatial patterns of Sorbus aucuparia recruitment in relation to topography and temporal changes in weather conditions, and found that the recruitment rate was not continuous. Two phases of rowan expansion were distinguished. In the first (before the 1970s), expansion depended on topography: northern and steep slopes were colonised and the development of thickets progressed from lower to higher elevations. In the second phase, starting in the 1970s, rowans crossed the historical timberline and on both northern and southern slopes was unrelated to topographical conditions. Moreover, in the last 60years, during which meteorological data were recorded, the rate of rowan expansion has been negatively correlated with precipitation and snow cover thickness. The temporal and spatial patterns of rowan recruitment on abandoned subalpine meadows indicate that land use changes were important in initiating the first stage of succession. Contrary to the common view and our own expectation that mildening of weather conditions facilitates colonisation of montane areas by trees, our results suggest that rowan expansion was positively associated with worsening of weather conditions (i.e. thinner snow cover and lower temperatures).

Leaf Tissue Water Relations Are Associated with Drought-Induced Leaf Shedding in Tropical Montane Habitats

In tropical montane areas, water limitation is a common occurrence, and both pioneer and forests species experience water stress during the dry season. Adjustments of leaf area during periods of drought allow for the maintenance of the water supply and physiological functions of the remaining leaves. Here, we compared leaf blade water relations between pioneer and forest tree species. Leaf pressure-volume (P-V) curves were determined from samples taken prior to the dry season, to assess how leaves of the different species were adapted to prepare for and endure water deficits. The following parameters were calculated: osmotic potential at full (Ψπ(100)) and zero (Ψπ(0)) turgor, relative water content at zero turgor (RWC0), volumetric elastic modulus (&#949) as well as apoplasm (A) and symplasm (S) water content and their ratio (A/S). Although the pioneer and forest species occupied contrasting habitats, and both groups were clearly differentiated with respect to their water transport capability and water use efficiency, their leaf tissue water relations showed clear differences across species but not between the groups. Some species underwent leaf shedding and accumulated xylem embolisms during the dry season, and their leaves had high cell elasticity. Consequently, these species presented large cell volume changes with turgor loss. Conversely, species with rigid leaves were able to undergo lower leaf turgor with only small changes in cell volume during drought, which might aid to preserve leaf cell function, maintain water uptake, and consequently avoid accelerated leaf senescence and shedding during the dry season.

Bird Ringing Data and Field Notes from The Kelabit Highlands: 1993 to 2010

The initial bird surveys of Sarawak, from 1985 to 1992, covered a few National Parks, and several other lowland sites. From January 1993, until November 2010, a new survey began, to explore a wide expanse of the Kelabit Highlands, including parts of the Pulong Tau National Park. During this eighteen-year period, the sites selected ranged from lower montane areas of the Kelabit plateau close to its border with Kalimantan to the higher montane slopes of Mount Murud massif to the north. The duration of these surveys, largely self-funded, ranged from short-term ones, of ten to fourteen days each, to several extended ones that lasted as long as three continuous months at the same location. A large volume of data, on 227 species, was collected during this time. A small part of it has been analysed to support a series of short papers previously published in The Sarawak Museum Journal. Much of it, however, especially the ringing data, remains unpublished. It is now released into public domain for use by other workers. The data collected in the lowland surveys will be published in a separate paper.

Estimating montane forest above-ground biomass in the upper reaches of the Heihe River Basin using Landsat-TM data

In this work, the results of above-ground biomass (AGB) estimates from Landsat Thematic Mapper 5 (TM) images and field data from the fragmented landscape of the upper reaches of the Heihe River Basin (HRB), located in the Qilian Mountains of Gansu province in northwest China, are presented. Estimates of AGB are relevant for sustainable forest management, monitoring global change, and carbon accounting. This is particularly true for the Qilian Mountains, which are a water resource protection zone. We combined forest inventory data from 133 plots with TM images and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) global digital elevation model (GDEM) V2 products (GDEM) in order to analyse the influence of the sun-canopy-sensor plus C (SCS+C) topographic correction on estimations of forest AGB using the stepwise multiple linear regression (SMLR) and k-nearest neighbour (k-NN) methods. For both methods, our results indicated that the SCS+C correction was necessary for getting more reliable forest AGB estimates within this complex terrain. Remotely sensed AGB estimates were validated against forest inventory data using the leave-one-out (LOO) method. An optimized k-NN method was designed by varying both mathematical formulation of the algorithm and remote-sensing data input, which resulted in 3000 different model configurations. Following topographic correction, performance of the optimized k-NN method was compared to that of the regression method. The optimized k-NN method (R2 = 0.59, root mean square error (RMSE) = 24.92 tonnes ha–1) was found to perform much better than the regression method (R2 = 0.42, RMSE = 29.74 tonnes ha–1) for forest AGB retrieval over this montane area. Our results indicated that the optimized k-NN method is capable of operational application to forest AGB estimates in regions where few inventory data are available.

Description of a new montane freshwater crab (Crustacea: Potamidae: Geothelphusa) from northern Taiwan.

A new freshwater crab is described from a montane area in northern Taiwan based on morphological characters and molecular evidence. Geothelphusa cilan sp. nov., from the Cilan Forest, situated on the boundary of Hsinchu and Yilan (= Ilan) counties, is close to G. monticola Shy, Ng & Yu, 1994, and G. takuan Shy, Ng & Yu, 1994, but can be distinguished by its male first gonopod (G1) and the ratio of thoracic sternites. Molecular evidence from mitochondrial cytochrome oxidase subunit I (COI) also supports the identity of the new species.

The integripennis species group of Geocharidius Jeannel, 1963 (Carabidae, Bembidiini, Anillina) from Nuclear Central America: a taxonomic review with notes about biogeography and speciation.

Our review recognizes 15 species of the integripennis species group of Geocharidius from Nuclear Central America, include three species previously described (Geocharidius gimlii Erwin, Geocharidius integripennis (Bates) and Geocharidius zullinii Vigna Taglianti) and 12 described here as new. They are: Geocharidius andersoni sp. n. (type locality: Chiapas, Chiapas Highlands, Cerro Huitepec) and Geocharidius vignatagliantii sp. n. (type locality: Chiapas, Motozintla, Sierra Madre de Chiapas, Benito Juárez) from Mexico; Geocharidius antigua sp. n. (type locality: Sacatepéquez, 5 km SE of Antigua), Geocharidius balini sp. n. (type locality: Suchitepéquez, 4 km S of Volcan Atitlán), Geocharidius erwini sp. n. (type locality: Quiché Department, 7 km NE of Los Encuentros), Geocharidius jalapensis sp. n. (type locality: Jalapa Department, 4 km E of Mataquescuintla), Geocharidius longinoi, sp. n. (type locality: El Progreso Department, Cerro Pinalón), and Geocharidius minimus sp. n. (type locality: Sacatepéquez Department, 5 km SE of Antigua) from Guatemala; and Geocharidius celaquensis sp. n. (type locality: Lempira Department, Celaque National Park), Geocharidius comayaguanus sp. n. (type locality: Comayagua Department, 18 km ENE of Comayagua), Geocharidius disjunctus sp. n. (type locality: Francisco Morazán, La Tigra National Park), and Geocharidius lencanus sp. n. (type locality: Lempira Department, Celaque National Park) from Honduras. For all members of the group, adult structural characters, including male and female genitalia, are described, and a taxonomic key for all members of the integripennis species group is presented based on these characters. Behavioral and biogeographical aspects of speciation in the group are discussed, based on the morphological analysis. In all cases of sympatry, pairs of closely related species show greater differences in sizes than pairs of more remotely related species. Integripennis group species occupy six different montane areas at elevations above 1300m, with no species shared among them. Major faunal barriers in the region limiting present species distributions include the Motagua Fault Zone and a gap between the Guatemalan Cordillera volcanic chain and the Honduran Interior Highlands no higher than 900m in elevation. Highest species diversity is in the Guatematan Cordillera (six species), second highest in the Honduran Interior Highlands area (four species).

Pacific and Atlantic oceanic anomalies and their interaction with rainfall and fire in Bolivian biomes for the period 1992–2012

Bolivia is located at the crossroad of the major climatic influences of Northern and Southern-South America, which turns this country into a natural laboratory to investigate the interactions between ocean-climate and fire variability. We chose two oceanic indices: MEI (multivariate ENSO Index) and AMO (Atlantic Multidecadal Oscillation) to select the three most representative years for four oceanic conditions: El Nino, La Nina, AMO, and standard years (understood as years with little ocean influences), for the period 1992–2012. We investigated how i) rainfall (dry vs wet seasons) and ii) fire responded in five Bolivian biomes (Tropical Moist Forests, Tropical Dry Forests, Tropical Grasslands, Tropical Montane, and Seasonally Flooded ecosystems) under these oceanic conditions. Bolivia showed a strong rainfall increase in El Nino years in both seasons (wet/dry), while AMO showed the strongest droughts in both seasons. La Nina showed a bipolar response with rainfall increases in the wet season and a very marked rainfall decrease in the dry season. Drought significantly increased fire numbers in AMO years, being the most significant fire condition and suggesting a larger fire influence of the Atlantic than the Pacific at the national level. Surprisingly, the amount of fire was very large under normal years (STD) and similar to fire levels under La Nina, suggesting generalized fire conditions in the country, except for El Nino years that bring rainfall excess and little fire. The most fire-affected biomes were the seasonally flooded and dry forests, followed by the grassland/savannah biome. Montane areas showed the least fire, but satellite fire omission is well known in the Andean region.

Testing diversification models of endemic Philippine forest mice (Apomys) with nuclear phylogenies across elevational gradients reveals repeated colonization of isolated mountain ranges

AbstractAimOur aims were to document the extent of diversification in an endemic clade of small mammals (Apomys, subgenus Megapomys) on a large oceanic island and to test whether speciation occurred primarily (1) along isolated elevational gradients or (2) among montane areas, as would be expected if diversification were driven by glacial cycles.LocationThe Philippine archipelago, particularly Luzon Island and two smaller adjacent islands (Mindoro and Lubang).MethodsWe analysed newly generated nuclear DNA sequences from five unlinked genes and mitochondrial cytochrome b using concatenation (likelihood and Bayesian) and coalescent‐based methods to estimate the species tree for all 13 species. We tested a priori models of speciation using both topological constraints and reconstructed elevational ranges of ancestors.ResultsAll individual gene trees recovered at least four of the morphologically defined Megapomys species as monophyletic, while the concatenated approaches recovered all 13 species as monophyletic. Each species was confined to a single mountain range or off‐shore island. Most mountain ranges had two species, but these species pairs usually were not sisters. Megapomys originated at medium to high elevation followed by three transitions into lower elevations and possibly one to high elevation. Both a priori models of speciation (elevational gradient and glacial cycle) were rejected by topology tests. The speciation rate was approximately constant through time.Main conclusionsNuclear sequence data strongly corroborated the species status of recently described taxa. A well‐supported phylogeny showed that Megapomys diversified by splitting into a predominantly high‐elevation clade and an entirely low‐elevation clade. Neither adaptation along elevational gradients on single mountain ranges nor vicariance of high‐elevation species following glacial cycle‐induced dispersals fitted the data. Rather, the most likely process explaining species distributions is repeated colonization of isolated mountain ranges by distantly related species.

Large‐scale rock slope failures in the eastern pyrenees: identifying a sparse but significant population in paraglacial and parafluvial contexts

This first overview of large‐scale rock slope failure (RSF) in the yrenees addresses the eastern third of the range. Around 30 principal RSFs greater than 0.25 km2 and 20 lesser or uncertain cases have been identified from remote imagery and groundtruthing. Compared with other European mountain ranges, RSF incidence is relatively sparse, displays no obvious regional trend or spatial clustering, and occurs across diverse landscape types, if mainly on metamorphic rocks. A transition is observed from paraglacial RSFs in formerly glaciated valleys to what are here termed ‘parafluvial’ RSFs, within wholly or mainly fluvial valleys but where slope failure is not directly provoked by or linked to river erosion. RSFs are particularly found in three topographic settings: at cirque and trough‐head thresholds (transition zones of elevated instability between cirque and main glaciated trough walls); near the upper or outer periphery of the ice field, where glacial adaptation of fluvial valleys is incomplete; and in fluvial valleys beyond glacial limits where incision is locally intense. RSF is absent from the range divide, from within cirques, and from most main valleys. In the montane areas, RSF is strongly associated with vestiges of preglacial summit surfaces, confirming that plateau ridges are less stable than sharpened crests and horns. RSF is contributing significantly to the progressive destruction of this paleic relief. The overall sparsity of RSF indicates insufficient rock mass stresses, including rebound after concentrated bedrock erosion. This may reflect a relatively weak imprint of glacial erosion, including breaching, in a context of relatively low mean rates of neotectonic uplift, possibly signalling overall that eastern yrenees landscapes are close to dynamic equilibrium.

Impacts of anthropogenic emissions and cold air pools on urban to montane gradients of snowpack ion concentrations in the Wasatch Mountains, Utah

Urban montane valleys are often characterized by periodic wintertime temperature inversions (cold air pools) that increase atmospheric particulate matter concentrations, potentially stimulating the deposition of major ions to these snow-covered ecosystems. We assessed spatial and temporal patterns of ion concentrations in snow across urban to montane gradients in Salt Lake City, Utah, USA, and the adjacent Wasatch Mountains during January 2011, a period of several persistent cold air pools. Ion concentrations in fresh snow samples were greatest in urban sites, and were lower by factors of 4–130 in a remote high-elevation montane site. Adjacent undeveloped canyons experienced significant incursions of particulate-rich urban air during stable atmospheric conditions, where snow ion concentrations were lower but not significantly different from urban sites. Surface snow ion concentrations on elevation transects in and adjacent to Salt Lake City varied with temporal and spatial trends in aerosol concentrations, increasing following exposure to particulate-rich air as cold air pools developed, and peaking at intermediate elevations (1500–1600 m above sea level, or 200–300 m above the valley floor). Elevation trends in ion concentrations, especially NH4+ and NO3−, corresponded with patterns of aerosol exposure inferred from laser ceilometer data, suggesting that high particulate matter concentrations stimulated fog or dry ion deposition to snow-covered surfaces at the top of the cold air pools. Fog/dry deposition inputs were similar to wet deposition at mid-elevation montane sites, but appeared negligible at lower and higher-elevation sites. Overall, snow ion concentrations in our urban and adjacent montane sites exceeded many values reported from urban precipitation in North America, and greatly exceeded those reported for remote snowpacks. Sodium, Cl−, NH4+, and NO3− concentrations in fresh snow were high relative to previously measured urban precipitation, with means of 120, 117, 42, and 39 μeq l−1, respectively. After exposure to atmospheric particulate matter during cold pool events, surface snow concentrations peaked at 2500, 3600, 93, and 90 μeq l−1 for these ions. Median nitrogen (N) deposition in fresh urban snow samples measured 0.8 kg N ha−1 during January 2011, with similar fog/dry deposition inputs at mid-elevation montane sites. Wintertime anthropogenic air pollution represents a significant source of ions to snow-covered ecosystems proximate to urban montane areas, with important implications for ecosystem function.

Conceptual Modelling to Assess Hydrological Impacts and Evaluate Environmental Flow Scenarios in Montane River Systems Regulated for Hydropower

To improve understanding of natural and managed flow regimes in data-sparse regulated river systems in montane areas, the commonly used Hydrologiska Byråns Vattenbalansavdelning (HBV) conceptual run-off model was adapted to incorporate water regulation components. The extended model was then applied to the heavily regulated river Lyon (391 km2) in Scotland to reconstruct the natural flow regime and to assess the impacts of regulation at increasing spatial scales. Multi-criteria model evaluation demonstrated that the model performed well in capturing the dominant catchment processes and regulation effects, especially at the timescales at which operation rules apply. The main change as a result of regulation in the river Lyon is a decrease in inter-annual and intra-annual variability of all elements of the flow regime, in terms of magnitude, frequency, and duration. Although these impacts are most pronounced directly downstream of the impoundments, the regulation effects propagate throughout the river system. The modelling approach is flexible and widely applicable and only limited amounts of data are required. Moreover, results are easily communicated to stakeholders. It has the potential to contribute to the development of flow regimes that may be more beneficial to the ecological status of rivers. In the case of the river Lyon, it is likely that this involves a more variable release regime. The approach developed here provides a tool for assessing impacts on flow regimes and informing environmental flows in other data-sparse regions with heavily regulated montane river systems. Copyright © 2014 John Wiley & Sons, Ltd.

Joint toxicity of chlorpyrifos and endosulfan to Pacific treefrog (Pseudacris regilla) tadpoles.

Recent ecotoxicology studies have focused on the potential interaction of pesticides and the effects these interactions may have on aquatic ecosystems. We examined the combined effects of two insecticides, endosulfan and chlorpyrifos, that have been previously examined individually on survival, growth, and development of Pacific treefrog (Pseudacris regilla) tadpoles. Historically, both pesticides have been heavily used in the Central Valley of California, been identified in downwind montane areas, and are highly toxic to amphibian larvae. Tadpoles were exposed to chlorpyrifos and endosulfan individually and in combination from Gosner stage 25 through metamorphosis to evaluate the individual effects and the interaction between these insecticides. Chlorpyrifos alone did not affect survival or body size after 30days, even at concentrations greater than the previously reported LC50. Survival and body size decreased with increasing endosulfan concentrations. The interactive effects of the insecticides depended on concentration and exposure duration. In combination, 137µg/L chlorpyrifos inhibited the negative effects of endosulfan on growth and survival. The presence of both insecticides in combination facilitated the development of axial malformations. In the presence of endosulfan with either 266 or 394µg/L chlorpyrifos, malformations occurred in 33 and 87% of tadpoles, respectively. Our results indicate that organophosphorus and organochlorine pesticides with different modes of action can result in varying interactions depending on their concentrations and on the end points being assessed. Further examination of contaminant impacts on natural aquatic systems should continue to focus on the effects of multiple contaminants and their potential for unpredictable, nonadditive interactions.

Náčrt strategické mapy obcí s využitím metody Balanced Scorecard

The article covers the compilation of a strategic map of four municipalities in a montane and submontane area in the region of The Novohradske Mountains in South Bohemia. The map was compiled on the basis of the Balanced scorecard (BSC) method. It is a tool by which the fulfilment of a municipality strategy can be monitored and it is used for an effective management of strategies. In other words it means a method of balanced indicators or balanced prosperity. Goals and benchmarks of BSC come from vision and strategy of these municipalities and they monitor their performance from four perspectives: customer, financial, internal processes, learning and growth. These four perspectives are clearly depicted in the strategic map and each one has more detailed definitions of benchmarks of their fulfilment.

Phylogenetics and taxonomy of the New World leafy spurges,EuphorbiasectionTithymalus(Euphorbiaceae)

The 480 species of leafy spurges, Euphorbia subgenus Esula, represent the main temperate radiation in the large genus Euphorbia. This group is distributed primarily in temperate Eurasia, but with smaller, disjunct centres of diversity in the mountains of the Old World tropics, in temperate southern Africa and in the New World. The majority of New World diversity (32 species) occurs in a single section, section Tithymalus. We analysed sequences of the nrITS and plastid ndhF, trnH-psbA, trnS-trnG and trnD-trnT regions to reconstruct the phylogeny of section Tithymalus and to examine the origins and diversification of the species native to the New World. Our results indicate that the New World species of section Tithymalus form a clade that is sister to the widespread, weedy E. peplus. The New World species fall into two primary groups: a ‘northern annual clade’ from eastern North America and a diverse clade of both annual and perennial species that is divided into three subgroups. Within the second group, there is a small ‘southern annual clade’ from Texas and northern Mexico, a perennial ‘Brachycera clade’ from the western United States and northern Mexico, and a perennial ‘Esuliformis clade’ from montane areas of Mexico, Guatemala, Honduras and the Caribbean island of Hispaniola. Ancestral state reconstructions indicate that the annual habit probably evolved in the ancestor of E. peplus and the New World clade, with a subsequent reversal to the perennial habit. In conjunction with this phylogenetic framework, the New World species of section Tithymalus are comprehensively reviewed. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175, 191–228.

Time-spatial distribution of Pinus in the Korean Peninsula

Despite the ecological and landscape importance and the public popularity of conifers, especially in the case of Pinus of Pinaceae in the Korean Peninsula, not much scientific information related to vegetation is known. A wide range of fossil data has been collated and analyzed to understand the past vegetation history and current distribution and ecology, and to predict the future ranges of Pinus species in Korea in connection with climate change.Though the existing earliest Pinus (diploxylon) dates to the Cretaceous, Pinus became more common since the Miocene, and shows widespread distribution in lowland and montane areas during the Quaternary. Separation of geographical distribution of haploxylon and diploxylon Pinus since the Pleistocene may be the result of the climatic fluctuations and availability of diverse habitat. Dominance of Pinus during the Holocene may be related to both natural climatic warming as well as anthropogenic disturbance, such as, selective deforestation, agricultural activities and fire.The present occurrence of cold-tolerant Pinus pumila at northern and central alpine and subalpine belts of the Korean Peninsula indicates that the cool and hostile climate at high elevation guaranteed the survival of glacial relics in post glacial climate. The presence of Pinus koraiensis at mid elevations on mountains of northern and central Korea might be due to the cool climate in the Pleistocene.Thanks to a mild climate and seeds with wings, combined with an abundance of poor soil provided by human disturbance, Pinus densiflora became a dominant tree species at lowland and montane areas. The presence of Pinus thunbergii mainly along southern coastal regions may also be related to the local climatic condition. Disjunctive distributions of Pinus parviflora on remote islands, such as Ulleung Island and some Japanese Isles, demands further study regarding the long distance dispersal of seeds by birds, and relation to an oceanic climate. More information is needed to discuss the distributions of Pinus tabulaeformis var. mukdensis at sites in northern Korea. Special concern and protection are required for vulnerable conifer species with limited or narrow distributional ranges on high mountains and in rapidly changing environments, due climate change and environmental degradation.

Air temperature suitability for Plasmodium falciparum malaria transmission in Africa 2000-2012: a high-resolution spatiotemporal prediction.

BackgroundTemperature suitability for malaria transmission is a useful predictor variable for spatial models of malaria infection prevalence. Existing continental or global models, however, are synoptic in nature and so do not characterize inter-annual variability in seasonal patterns of temperature suitability, reducing their utility for predicting malaria risk.MethodsA malaria Temperature Suitability Index (TSI) was created by first modeling minimum and maximum air temperature with an eight-day temporal resolution from gap-filled MODerate Resolution Imaging Spectroradiometer (MODIS) daytime and night-time Land Surface Temperature (LST) datasets. An improved version of an existing biological model for malaria temperature suitability was then applied to the resulting temperature information for a 13-year data series. The mechanism underlying this biological model is simulation of emergent mosquito cohorts on a two-hour time-step and tracking of each cohort throughout its life to quantify the impact air temperature has on both mosquito survival and sporozoite development.ResultsThe results of this research consist of 154 monthly raster surfaces that characterize spatiotemporal patterns in TSI across Africa from April 2000 through December 2012 at a 1 km spatial resolution. Generalized TSI patterns were as expected, with consistently high values in equatorial rain forests, seasonally variable values in tropical savannas (wet and dry) and montane areas, and low values in arid, subtropical regions. Comparisons with synoptic approaches demonstrated the additional information available within the dynamic TSI dataset that is lost in equivalent synoptic products derived from long-term monthly averages.ConclusionsThe dynamic TSI dataset presented here provides a new product with far richer spatial and temporal information than any other presently available for Africa. As spatiotemporal malaria modeling endeavors evolve, dynamic predictor variables such as the malaria temperature suitability data developed here will be essential for the rational assessment of changing patterns of malaria risk.

The influence of the complex topography and dynamic history of the montane Neotropics on the evolutionary differentiation of a cloud forest bird (Premnoplex brunnescens, Furnariidae)

AbstractAimTo examine the effect of geographical barriers and habitat dynamics related to climatic oscillations on the phylogeography of a widespread passerine of Neotropical cloud forests, the spotted barbtail (Premnoplex brunnescens).LocationNeotropical humid forests of montane areas in lower Central America and South America.MethodsWe sequenced two mitochondrial genes and one nuclear intron from specimens collected across the distribution of P. brunnescens. Phylogenetic relationships were inferred using Bayesian and maximum‐likelihood methods. Groups with maximum differentiation were estimated with spatial analysis of molecular variance (SAMOVA). We estimated timing of differentiation and relationships among groups with a species‐tree approach and historical demography with extended Bayesian skyline plots.ResultsSix highly differentiated clades of P. brunnescens are distributed in lower Central America, Sierra Nevada de Santa Marta, northern Venezuelan mountains, the Northern Andes, central Peru, and southern Peru and Bolivia. Within the Northern Andes clade, six phylogroups were identified associated with different slopes and isolated cordilleras. Most clades occupy opposite sides of low‐lying valleys and ridgelines, but little differentiation was observed across several putative barriers. Population divergence occurred in the late Miocene and Pliocene, perhaps in association with Andean uplift. Historical fluctuations in population sizes suggest that populations tracked the spatial dynamics of montane forests associated with glacial cycles.Main conclusionsExtensive genetic differentiation in mitochondrial and nuclear DNA exists among populations of P. brunnescens. Such marked divergence was probably promoted by the rugged topography and dynamic ecological history of the Neotropical mountains. Our study sheds light on mechanisms promoting population differentiation in the montane Neotropics.

Rapid acclimation to cold allows the cane toad to invade montane areas within its Australian range

Summary The cane toad (Rhinella marina) invasion of Australia has now reached areas much colder than most of its native range in tropical America. Understanding the toad's ability to function in such conditions can clarify its potential for further spread. In northeastern New South Wales (NSW), cane toads have been recorded up to 1100 m above sea level (asl). Our monitoring over summer 2012–2013 confirmed that ground temperatures were lower at three high‐elevation (750–1010 m asl) sites than at two nearby lower (100–210 m asl) sites (by day, 18°C vs. 25°C; at night, 17–18°C vs. 20–25°C, respectively). Critical thermal minima (CTmins) of field‐collected toads (loss of the righting reflex) were lower for high‐elevation than low‐elevation toads (5·5°C vs. 7·5°C), but laboratory acclimation abolished this difference. A toad's CTmin was not affected by site of collection, nor by 1 month's exposure to warm (24°C) or cool (12°C) conditions; instead, a toad's CTmin was determined by its thermal exposure over the previous 12 h. Locomotor ability was affected by test temperature, by elevation and by acclimation. Toads from high elevations exhibited equal endurance at cold and warm test temperatures after month‐long acclimation to cold conditions, whereas toads from low elevations performed better at high temperatures regardless of previous temperature treatments. Cane toads at the southern edge of their expanding Australian range can function under cool conditions by adjusting their thermal tolerance within a few hours of encountering low temperatures. The toads' ability for rapid thermal acclimation suggests that current models underestimate the potential range of abiotic conditions accessible to this invading species.

Matching species traits to projected threats and opportunities from climate change.

AimClimate change can lead to decreased climatic suitability within species' distributions, increased fragmentation of climatically suitable space, and/or emergence of newly suitable areas outside present distributions. Each of these extrinsic threats and opportunities potentially interacts with specific intrinsic traits of species, yet this specificity is seldom considered in risk assessments. We present an analytical framework for examining projections of climate change-induced threats and opportunities with reference to traits that are likely to mediate species' responses, and illustrate the applicability of the framework.LocationSub-Saharan Africa.MethodsWe applied the framework to 195 sub-Saharan African amphibians with both available bioclimatic envelope model projections for the mid-21st century and trait data. Excluded were 500 narrow-ranging species mainly from montane areas. For each of projected losses, increased fragmentation and gains of climate space, we selected potential response-mediating traits and examined the spatial overlap with vulnerability due to these traits. We examined the overlap for all species, and individually for groups of species with different combinations of threats and opportunities.ResultsIn the Congo Basin and arid Southern Africa, projected losses for wide-ranging amphibians were compounded by sensitivity to climatic variation, and expected gains were precluded by poor dispersal ability. The spatial overlap between exposure and vulnerability was more pronounced for species projected to have their climate space contracting in situ or shifting to distant geographical areas. Our results exclude the potential exposure of narrow-ranging species to shrinking climates in the African tropical mountains.Main conclusionsWe illustrate the application of a framework combining spatial projections of climate change exposure with traits that are likely to mediate species' responses. Although the proposed framework carries several assumptions that require further scrutiny, its application adds a degree of realism to familiar assessments that consider all species to be equally affected by climate change-induced threats and opportunities.

Mercury bioaccumulation in Southern Appalachian birds, assessed through feather concentrations

Mercury contamination in wildlife has rarely been studied in the Southern Appalachians despite high deposition rates in the region. From 2006 to 2008 we sampled feathers from 458 birds representing 32 species in the Southern Appalachians for total mercury and stable isotope δ (15)N. Mercury concentrations (mean±SE) averaged 0.46±0.02μgg(-1) (range 0.01-3.74μgg(-1)). Twelve of 32 species had individuals (7% of all birds sampled) with mercury concentrations higher than 1μgg(-1). Mercury concentrations were 17% higher in juveniles compared to adults (n=454). In adults, invertivores has higher mercury levels compared to omnivores. Mercury was highest at low-elevation sites near water, however mercury was detected in all birds, including those in the high elevations (1,000-2,000m). Relative trophic position, calculated from δ (15)N, ranged from 2.13 to 4.87 across all birds. We fitted linear mixed-effects models to the data separately for juveniles and year-round resident adults. In adults, mercury concentrations were 2.4 times higher in invertivores compared to omnivores. Trophic position was the main effect explaining mercury levels in juveniles, with an estimated 0.18±0.08μgg(-1) increase in feather mercury for each one unit rise in trophic position. Our research demonstrates that mercury is biomagnifying in birds within this terrestrial mountainous system, and further research is warranted for animals foraging at higher trophic levels, particularly those associated with aquatic environments downslope from montane areas receiving high mercury deposition.