Conservation Biogeography Research Articles

Comparative phylogeography, a tool to increase assessment efficiency of polar assemblage resilience and vulnerability

The Southern Ocean benthos is remarkably rich and diverse, and managed under a complexity of treaties and conventions, further complicated by geopolitical boundaries. Traditionally, conservation management is largely informed by species lists augmented, when data are available, by known vulnerability of the taxa. Species presence absence database resources are valuable tools with proven and positive management outcomes, however, in a vast, difficult to access and thus understudied region such as the Southern Ocean, there are large gaps in knowledge regarding the ecology, ecophysiology, life history and even species identity. Conservation biogeography identifies regions of conservation concern, rather than a species-by-species approach, but also relies on the availability of high-quality presence data from species lists and thus both approaches are undermined when species lists are inaccurate or species in general are poorly described. In addition, the data provide a snapshot of the current species diversity and have inadequate power to identify the processes underlying the patterns uncovered. Identifying historical processes common to shaping diversity (species or genetic) can be generalized across assemblages and regions, providing a more robust basis for conservation policy and decisions. In this study, largely based on consideration of Southern Ocean ophiuroids, we discuss the challenges inherent in using species lists, the power and limitations of genetic analyses, and revisit previous suggestions of building a spatial model of diversity that includes underlying evolutionary relationships transcending the simple species diversity approach, and that is applicable to assemblages, rather than just to individual taxa.

Conservation biogeography and diversity of tarantulas in Argentina

Abstract The loss of biodiversity due to the effects of a number of human activities is a cause for great concern. Protected areas are currently one of the main conservation tools worldwide and their correct selection and design play a key role. Since 2000, there have been protocols for systematic conservation planning, which emphasize the identification of priority conservation areas (PCAs) to ensure the persistence of species habitats and the environmental processes associated with them. Spiders of the family Theraphosidae (tarantulas) have biological characteristics that make them vulnerable to fragmentation in time and space and also are underrepresented in current conservation efforts. The geographical distribution of endemic species, such as tarantulas, represents a historical and ecological footprint of all biological entities; therefore, such endemic areas are recognized as priority areas for biodiversity conservation plans. The present work aims to develop an integrative biogeographical approach to conservation through the evaluation of multispecies distribution patterns, and the study of species richness and areas of endemism of tarantulas in Argentina with the ultimate goal of assessing their relationship to existing protected areas and proposing PCAs.

A new window for conservation biogeography

<p>Classic biogeography provides the context for understanding why large-scale patterns of biodiversity occur where they do. However, over the past half century, human activities have greatly changed biogeographic patterns and caused accelerating loss of biodiversity on the earth. In spite of the Launch of Conservation Biogeography a couple of decades ago, there has been no concerted effort to implement conservation practices for regional biodiversity by integrating ecology and evolution over geographical space and time. This paper presents lessons and experiences from biodiversity protection of the Yangtze River, demonstrating an urgent need for biogeography-based solutions that cannot be easily deduced from current conservation biogeography. We aim to open a new window for conservation biogeography by providing a new cross-level paradigm and a new definition, seeking for biogeographic strategies for the long-lasting preservation of regional biodiversity. We believe that this paper makes a concise conceptual advance in conservation biogeography.</p>

Conservation Biogeography of the Dwarf Lemurs (Cheirogaleus) of Madagascar, Investigated via Ecological Niche Modelling

Ecological niches are the environmental conditions under which an organism can maintain viable populations. A detailed understanding of an organisms’ ecological niche can provide information on its taxonomy and biogeography, and ecological niche modelling allows researchers to investigate how closely-related species are able to coexist. Ecological niche models also enable conservationists to determine species’ habitat requirements, map distributions, and assess threats. We used this approach to investigate the conservation biogeography of the dwarf lemurs (genus Cheirogaleus), a group of cryptic, nocturnal primates endemic to Madagascar. Using climatic and vegetation-related variables, we constructed ecological niche models for three species to investigate niche overlap among taxa. We also constructed maps of the availability of forest habitat, and we assessed anthropogenic risk and protection. Our ecological niche models and background tests indicated that each of the three analysed Cheirogaleus species occupies distinct environmental space. The area of suitable habitat (realized niche) varied interspecifically (28,889–41,934 km2). This also was mirrored by variation in the percentage of each species’ realized niche within protected areas (20,065–25,266 km2) and near anthropogenic features (5,744–16,999 km2). Our results support the 2020 taxonomy of the dwarf lemurs recognised by the IUCN Red List and provides information on their biogeography. Furthermore, our ecological niche models have highlighted that the habitat of some dwarf lemur species, such as C. crossleyi, are more threatened than other species, such as C. medius and C. major, and these species require urgent conservation attention.

Reconstructing mechanisms of extinctions to guide mammal conservation biogeography

AbstractAn emerging research program on population and geographic range dynamics of Australia's mammals illustrates an approach to better understand and respond to geographic range collapses of threatened wildlife in general. In 1788, Europeans colonized an Australia with a diverse and largely endemic mammal fauna, where many species that are now extinct or threatened were common and widespread. Subsequent population declines, range collapses and extinctions were caused by introduced predators and herbivores, altered land use, modified fire regimes and the synergies between these threats. Declines in population and range size continue for many Australian mammals despite legislative protection and conservation interventions. Here, we propose an approach that integrates museum data and other historical records into process‐explicit macroecological models to better resolve mammal distributions and abundances as they were at European arrival. We then illustrate how this integrative approach can identify the likely synergistic mechanisms causing mammal population declines across these and other landscapes. This emerging research approach, undertaken with fine temporal and spatial resolution, but at large geographic scales, will provide valuable insights into the different pathways to, and drivers of, extinction. Such insights may, in turn, underpin conservation strategies based on a process‐explicit understanding of population decline and range collapse under alternative scenarios of impending climate and environmental change. Given that similar information is available for other regional biotas, the approach we describe here can be adapted to conserve threatened wildlife in other regions across the globe.

Geographic variation of litter chemistry and palatability in an invasive plant versus its native competitor

AbstractAimLatitudinal variation in biotic interactions is recognized as a driver underlying variation in plant invasion success and therefore an important issue in conservation biogeography. However, previous studies have mainly focused on interactions between living plants and herbivores, whereas litter traits and detritivory have been hardly studied along latitude or compared between native and invasive plants. Our aim was to compare latitudinal variation in leaf litter chemistry and palatability to detritivores between invasive and native plants, and investigate which chemical traits determine detritivory and whether they are climate‐driven.LocationChina.TaxaSpartina alterniflora, Phragmites australis, Porcellio laevis, Chiromantes dehaani.MethodsWe combined field surveys with laboratory experiments to compare latitudinal variation in litter chemistry between the widespread invasive Spartina alterniflora and its native competitor Phragmites australis across their co‐occurring range (20.9–40.7° N, ~2200 km). For both species, we examined litter palatability to two common detritivores (Porcellio laevis and Chiromantes dehaani) along the same latitude. We also analysed relationships among climate, litter traits and detritivory.ResultsIn five of nine litter traits, we found latitudinal clines, with little difference between the two plant species in how they responded across the gradient. Litter palatability decreased with increasing latitude, but was generally higher in Spartina than Phragmites. Two key litter traits (C:P ratio and flavonoid content) were significantly associated with temperature of origin and with detritivory.Main ConclusionsThere were geographic clines in litter traits and palatability, with strong links between climate, litter chemistry and detritivory, in both Spartina and Phragmites. Spartina litter, however, was more rapidly decomposed by detritivores, which could create positive feedbacks, and contributes to the successful Spartina invasion along China's coast. Future ecological restoration projects should therefore dispose Spartina plant tissue or litter off‐site, to reduce the competitiveness of Spartina and support the conservation of native Phragmites.

Wildlife Wrangler: A high-level data processing framework that supports the utilization of species occurrence data for biogeographical analyses

Wildlife Wrangler: A high-level data processing framework that supports the utilization of species occurrence data for biogeographical analyses

Biogeography of terrestrial vertebrates and its conservation implications in a transitional region in western Mexico.

Conservation biogeography, which applies principles, theories, and analyses of biodiversity distribution patterns to address conservation challenges, can provide valuable insight and guidance to policy making for protection of biodiversity at multiple scales. The temperate and tropical ecosystems of the Nearctic-Neotropical transition in the small western state of Colima, Mexico, support a mosaic of remarkably diverse fauna and flora and provide a rare opportunity to determine spatial distribution patterns of terrestrial vertebrate species, assess human-induced threats, and identify potential conservation strategies. We analyzed the spatial distribution patterns and correlated them with the current land cover and extent of the protected areas. Despite its limited geographic extension, 29% (866) of all vertebrates, and almost a quarter of both endemic and threatened species in Mexico, live in Colima. Our analysis identified clear high-richness concentration sites (i.e., “hotspots”) coincident for all groups and that elevation and both temperate and tropical ecosystems composition exert significant influence on richness patterns. Furthermore, current species´ distribution also showed significant correlation with natural and disturbed landcover. Significant hotspots for all species groups coincided poorly with the limited protected areas in the state (only 3.8%). The current state of natural land cover (less than 16%) in the state, coupled with its remarkable biological importance, highlights the need for further complementary conservation efforts including expansion and creation of new protected areas, significant restoration efforts and other conservation measures to maintain this uniquely biogeographic and biological diverse region of the country.

A simple and extensible framework to identify key areas for the conservation of single vulnerable freshwater species

One of the main challenges in conservation biogeography of freshwater fishes is the improvement of conservation planning strategies. Nonetheless, the implementation of such strategies has lagged in freshwater systems, limiting their protection to the priorities of land organisms. Since the repercussions and relative importance for conservation across freshwater species can vary tremendously, and the application of such strategies requires information on multiple species, it is valuable to consider extensible and straightforward approaches that can be applied to single species. Here we use a freshwater fish species native to the Colombian Andes (Brycon henni) as a model to implement a methodology for spatial conservation prioritization considering four criteria: i) representativeness (protection of species distribution), ii) viability (maximizing probability of success), iii) complementarity (recognition of the currently protected area network), and iv) connectivity (promoting connectivity amongst protected areas). Using the proposed methodology based on the potential distribution of B. henni and hydrographic sub-basins as planning units, we recommend the protection of nine sub-basins climatically suitable for the species and with strategic river corridors that would promote the connection amongst basins and the currently protected areas. This methodological proposal can contribute to the current strategy design implemented by the National System of Protected Areas in Colombia to conserve or recover ecosystems and fragmented natural habitats, providing design options that meet ecological and socioeconomic objectives. Lastly, we consider that the methodology proposed here could be used with a more significant number of species of interest and implemented on a regional and global scale.

Sticking around: Plant persistence strategies on edaphic islands

AbstractAimSpecies on islands are at high risk of extinction due to environmental changes, including global warming, land‐use alterations and invasions. At local scales, extinctions can be offset by strategies promoting in situ persistence. We explored how persistence‐related traits of plants—that is, linked to belowground resource conservation, growth, size and longevity—on edaphic islands respond to variation in insularity and the environment (soil and microclimate), including intraspecific variability, which is rarely considered in functional island biogeography. We hypothesised that plants facing strong insularity and harsh soil conditions are characterised by enhanced persistence abilities.LocationShallow‐soil temperate dry grasslands on granite outcrops, Central Europe.MethodsWe focussed on edaphic island specialist species belonging to different life histories, namely clonal and non‐clonal perennial plants. We used linear and linear mixed‐effect models to examine intra‐ and interspecific trait patterns versus variation in insularity, soil and microclimate.ResultsInsularity tended to promote smaller plants (non‐clonal species) and belowground resource‐conservative strategies (both clonal and non‐clonal species), increasing the likelihood of local persistence. Soil also contributed largely to explaining persistence‐related trait patterns: plants growing in harsh soil conditions tended to be resource conservative. Clonal species are distinguished by highly consistent responses to variation in insularity and soil conditions, whereas non‐clonal plants showed distinct species‐specific responses.Main conclusionsOur findings have important implications for the conservation biogeography of edaphic island plant specialists. Clonal species may be susceptible to local extinction should insularity or soil conditions vary, for example, due to abrupt changes in the geographical setting (e.g. habitat loss) or local environmental factors (e.g. N‐deposition). Non‐clonal species may instead face environmental changes differently; some will go extinct, whereas others will survive, depending on the prevailing abiotic pressures. This seems to challenge previous views that predicted clonal species to be the winners and non‐clonal species the losers against local extinction.

Floristic composition and phytogeographical spectrum of Pistacia vera L. woodland remnants in northeastern Iran

The xerophilic woodlands of wild pistachio Pistacia vera L. remnants occur as several isolated stands in Central Asia. The Kopet Dagh mountain range, northeastern Iran, is the westernmost distribution range of wild pistachio. In this research, we present the annotated checklist of vascular plants of two remnants of P. vera woodlands along the Iran–Turkmenistan borders. We provide the life‐forms, phytogeographical spectrum, endemism and conservation status of the flora. The field surveys were conducted through several field collection efforts during 2018–2020. A map showing the boundaries of the woodlands was prepared. We recorded 348 plant species distributed in 214 genera and 48 families. The richest families were Asteraceae (33 genera with 59 species), Poaceae (22 with 41), Brassicaceae (24 with 28) and Fabaceae (11 with 27), and the two richest genera were Astragalus (ten species) and Galium (nine species). The dominant life‐forms were therophytes (54%) and hemicryptophytes (24%), which confirm a xeric climate condition. Irano–Turanian elements (195 species, 56%) were the most common plants, followed by bi‐regional (21%) elements. Based on our samplings, the Khorassan‐Kopet Dagh endemics represented only four percent of the flora. We recorded 34 endemics/sub‐endemics of plants, eight of which were categorized as threatened or near‐threatened. The results indicated the important role of pistachio remnant woodlands in plant biodiversity and conservation biogeography of northeastern Iran.

Population density estimates for terrestrial mammal species

AbstractAimPopulation density is a key parameter in ecology and conservation, and estimates of population density are required for a wide variety of applications in fundamental and applied ecology. Yet, in terrestrial mammals these data are available for only a minority of species, and their availability is taxonomically and geographically biased. Here, we provide the most plausible predictions of average population density, their natural variability and statistical uncertainty for 4,925 terrestrial mammal species.LocationGlobal.Time period1970–2021.Major taxa studiedTerrestrial mammals.MethodsWe fitted an additive mixed‐effect model accounting for spatial and phylogenetic autocorrelation on a dataset including 5,412 average population density estimates for 737 species. Average density was modelled as a function of body mass, diet, locomotor habits and environmental conditions. We validated the model using spatial and taxonomic block cross‐validation and used the estimated error to quantify the uncertainty around statistical predictions of population density for 4,925 mammal species.ResultsSmall body size, fossorial behaviour and herbivorous diets were associated with the highest population densities, whereas large size, aerial behaviour and carnivorous diets were related to the lowest densities. Species in non‐seasonal environments yielded higher densities than species in environments with high precipitation seasonality. Empirical estimates of population density vary by about four times on average within the same species, and statistically independent predictions for the majority of species deviate by about five times from observed values, indicating that prediction errors are similar to the natural variability in population densities.Main conclusionsOur predictions and uncertainty estimates of average population densities open up a number of applications in macroecology and conservation biogeography, including biomass estimation, setting population targets in conservation assessments and planning, and supporting Red List assessments. The methodology can be replicated easily for other taxonomic groups with a representative sample of georeferenced density estimates.

Translocation experiment gives new insights into the navigation capacity of an African duck

AbstractAimMovement is integral to the distribution and abundance of wildlife. We undertook an experimental test of the navigation capacity of Egyptian Geese Alopochen aegyptiacus to better understand the movements of moult‐migratory waterfowl and the implications of navigation capacity for their ecology.LocationSouthern Africa. In June 2015, we translocated six post‐flightless moult Egyptian Geese 1250 km south, from north‐west South Africa (Barberspan) to the south‐west coast (Strandfontein). We compared their movements to those of 29 previously tracked resident Egyptian Geese from the source and translocation sites, and three additional sites (Voelvlei; Jozini Dam; Lake Manyame, north‐central Zimbabwe).MethodsWe used solar‐powered satellite GPS to track movement patterns and compared the movement paths of different birds using net‐squared displacement analysis and multiple regression analysis of different measures of movement paths.ResultsOver time periods up to 658 days, none of the translocated Egyptian Geese returned to Barberspan and only one appeared to fly towards it. Translocated birds showed some novel and risky behaviours. Longer, searching‐type movements were evident with the onset of both the breeding and moulting seasons. Quantitative comparisons suggested that translocated birds retained elements of learned behaviours.Main conclusionsNavigation by Egyptian Geese appears to have a strong learned (internal) element, with long‐distance movement triggered by internal states such as the need to moult. Translocated animals modified their movement patterns in ways that mostly allowed them to survive. Our results have interesting implications for understanding the dynamics of individual populations; a strong reliance on learned behaviours may explain the unresolved conundrum of why no African duck species has colonized Europe without human assistance. Our analysis demonstrates the complexity of influences on animal movement and highlights the importance of navigation capacity for conservation biogeography.

Species distribution modeling to inform transboundary species conservation and management under climate change: promise and pitfalls

Spatially explicit biogeographic models are among the most used methods in conservation biogeography, with correlative species distribution models (SDMs) being the most popular among them. SDMs can identify the potential for species’ and community range shifts under climate change, and thus can inspire, inform, and guide complex and adaptive conservation management planning efforts such as collaborative transboundary conservation frameworks. However, SDMs are rarely developed collaboratively, which would be ideal for conservation applications of such models. Further, SDMs that are applied to conservation often do not follow best practices of the field, which are particularly important for applications in climate change contexts for which model extrapolation into potentially novel climates is necessary. Thus, while there is substantial promise, particularly among machine-learning based SDM approaches, there are also many pitfalls to consider when applying SDMs to conservation, and especially in the context of transboundary management under climate change. Here, we summarize these pitfalls and the key steps to mitigate them and maximize the promise of applying SDMs to facilitate transboundary conservation planning under climate change. We argue that conservation modeling capacity must be elevated among practitioners such that they can easily implement best practices when using SDMs, especially regarding: 1) avoiding model overcomplexity, 2) addressing input data bias, and 3) accounting for uncertainty in model extrapolations and projections. While our discussion centers mainly on the pitfalls and opportunities of applying the most popular correlative SDM algorithm, Maxent, our suggestions can also be generalized to a range of other SDM tools. Overall, improved training in, tools for, and implementation of best practices in biogeographic models such as SDMs hold great promise to facilitate and help guide complex, transboundary collaborations for long-term planning of conservation under climate change.

Conservation biogeography of high‐altitude longhorn beetles under climate change

Abstract High‐altitude insects are expected to be strongly affected by climate change because of their limited range. Phytophagous species will be subject to further threats because of their dependence on host plants. We investigated the impact of climate change on the distribution of Italian high‐altitude longhorn beetles (Cerambycidae) using a maximum entropy approach based on bioclimatic variables. We used 510 presence records for 15 species distributed throughout the Italian Alps and Apennines. Then, we combined climate‐based predictions with vegetation data to predict the future changes in the extent of suitable areas. All species but two will move uphill to track suitable climates and will face a range contraction (with an average loss of 44%) under both climatic change scenarios considered. Suitable vegetation covers, on average, only 56% of the estimated current species ranges, which means that the future distribution will be even more limited. Given the importance of Italian mountains as hubs of diversity in the Mediterranean hotspot, these results are particularly alarming. Conservation actions that can mitigate the effects of climate change on high‐altitude cerambycids should be focused on contrasting habitat loss and degradation through land preservation and the adoption of appropriate forest management practices.

Niche-separation and conservation biogeography of Madagascar’s fork-marked lemurs (Cheirogaleidae: Phaner): Evidence of a new cryptic species?

Ecological niche modeling can provide insights into a species’ demography, ecology and biogeography, and the environmental factors that determine them. Exploration of ecological niche models and niche-divergence among closely-related and cryptic organisms can also be useful for species delineation and discrimination, and such information can inform and facilitate conservation of their populations. In this study, I used an ecological niche modeling approach to investigate the conservation biogeography of the fork-marked lemurs (genus Phaner), a group of cryptic, nocturnal primates that are endemic to Madagascar. I constructed all ecological niche models in MaxEnt, using a range of climatic and habitat-related variables. I examined interspecific niche-separation within the Phaner genus, and among two sub-populations of P. electromontis, a species which has previously been hypothesized to represent two distinct, cryptic taxa. All ecological niche models performed well and with high accuracy, and whilst the percentage contribution of each environmental variable differed between species, the results suggested that climate may be the primary determinant of Phaner distribution. Further, all four Phaner species occupied distinct ecological niches, a result that was also mirrored in the two P. electromontis sub-populations. This suggests that one of the two sub-populations may indeed be a distinct, as-yet undescribed species, but further genetic and ecological research is needed to substantiate this result. Finally, the ecological niche models revealed that only 23.0% of the suitable land area for Phaner occurrence within Madagascar is forested, limiting the geographic distribution of these lemurs. Whilst much of this suitable habitat is thankfully protected, deforestation continues throughout Madagascar, and this under-studied group of lemurs requires further research attention and continued conservation efforts.

Advances in conservation biogeography: towards protected area effectiveness under anthropogenic threats

This study endorses the main findings of a PhD thesis (Hoffmann 2020) and the manuscripts included intend to advance the success of protected areas in biodiversity conservation mediated through effective and efficient protected area management. The manuscripts provide missing scientific evaluations that modern conservation planning over large geographical extents requires: the comprehensive quantification of species diversity within and between protected areas; the development and application of efficient and effective in-situ monitoring and remote sensing of species diversity; and the assessment of anthropogenic climate change threats to protected areas. Moreover, the manuscripts aim at spreading conservation-minded data and knowledge by means of publishing open-access papers, open-source software and open data. This thesis synopsis is to stimulate a growing scientific and public debate on the effectiveness of protected areas and nature conservation under anthropogenic threats, which is necessary to stop nature’s decline and thus guarantee a sustainable future for the welfare of generations to come.

Conservation biogeography of the terrestrial mammals in Iran: diversity patterns, and vulnerability to climate change and extinction

Under the framework of a “conservation biogeography” approach, initially, I reviewed and updated the taxonomy and distribution of the rich but understudied mammalian diversity of Iran. This data then formed the basis for the biogeographical regionalization of this complex transitional area using hierarchical clustering and infomap network methods. I used linear models to explore the correlates of extinction risk for this threatened mammalian fauna. Functional grouping of target species was used to assess their vulnerability to the magnitude and velocity of climate change impacts. Both clustering and network methods successfully illuminated the intricate biogeographic patterns, while the network detected many more small bioregions, including two transition zones. The extinction risk analyses revealed that human activities, such as hunting and persecuting (direct impacts) played a major role in the decline of these taxa, as opposed to minor effect of indirect and instrinsic and extrinsic factors. The magnitude and velocity of climate change impacts varied significantly between functional groups, with the highest risk of exposure to extreme climates in large and threatened species occurring in lowlands. This study provides a foundation for future biogeographic, systematics and ecological studies of Iranian mammals while simultaneously adding to the limited available information on the bioregionalization at regional scales. And it highlights the importance of incorporating threats in extinction risk models and functional trait information in climate change impact assessments.

Screening marker sensitivity: Optimizing eDNA‐based rare species detection

AbstractAimEnvironmental DNA (eDNA)‐based techniques are useful tools in disciplines such as conservation biogeography at local to global scales since they provide promising methods to locate organisms at low abundance. Here, we raise a largely overlooked issue that the marker (primer pairs and/or probes) sensitivity of eDNA‐based detection should be optimized and reported to improve detection performance and result interpretation.LocationGlobal.MethodsWe analysed 250 articles published between 2008 and 2019 that sought to detect animals from environmental water samples using species‐specific markers to identify effort required.ResultsMost (66.0%) studies used newly designed markers, and real‐time quantitative PCR dominated the studies (72.4% of articles). The use of quantitative PCR increased significantly over time (p = .016), while conventional PCR decreased significantly (p = .005). In 82.4% of studies using newly designed markers, researchers did not screen their chosen markers for sensitivity, and 46.7% of these studies did not report the limit of detection (LoD). Limited knowledge of sensitivity screening and LoD was also found among aquatic species on the list of the world's worst alien invasive species, and many studies used published markers without such knowledge, potentially propagating errors.Main conclusionsThe rapidly growing use of eDNA‐based detection of low‐abundance species requires well‐designed protocols to improve sensitivity. Knowledge of the limits of eDNA technology is imperative, particularly when applied to conservation biogeography studies for detecting non‐indigenous or endangered species. Our results highlight the currently inadequate sensitivity screening of genetic markers used in most studies, contrasting the transition to highly sensitive PCR methods. Along with ongoing calls for standardization in the eDNA methods, we add that newly designed markers be screened to determine and optimize sensitivity before use to reduce the uncertainty of detection and benefit future applications within or beyond areas of their development.

Conservation Biogeography of Tenebrionid Beetles: Insights from Italian Reserves

The species-area relationship (SAR), the latitudinal gradient, the peninsula effect, and the elevational gradient are widespread biogeographical patterns. Using data from Italian reserves, these patterns were tested for tenebrionids and used as a framework to calculate expected extinction rates following area loss. Area was an important determinant of overall tenebrionid species richness, but not for xylophilous and endemic species. Thus, focusing on reserve areas is not the best approach for conserving insects with specialised ecology and restricted distribution. In general, species richness declined northwards, which contrasts with the peninsula effect, but conforms to the European latitudinal pattern observed in most taxa because of current and past biogeographical factors. Minimum elevation had an overall negative influence, as most tenebrionids are thermophilic. However, xylophilous tenebrionids, which are mainly associated with mesophilic forests, did not decline northwards, and were positively influenced by higher elevational ranges that allow more forms of vegetation. SAR-based extinction rates reflect species dispersal capabilities, being highest for geophilous species (which are mainly flightless), and lower for the xylophilous species. Extinction rates based on multiple models indicate that the use of area alone may overestimate extinction rates, when other factors exert an important role in determining species richness.