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The data collected by the Global Biodiversity Information Facility (GBIF), some 2.2 billion records, is arguably the largest international initiative to digitize and share primary biodiversity data. In this study, we examine the global distribution of completeness values discriminating those 30-minute cells that are likely to have reliable inventories for the most important terrestrial classes of Animalia and Plantae. The aim of this exploration is not only to show the biases and deficiencies in the biodiversity information collected so far, but also to estimate the climatic variability represented by these data in order to known their representativeness for conservation purposes. The results obtained show that information on biodiversity distribution is taxonomically and geographically biased towards regions and groups with more taxonomic resources and a longer naturalistic tradition. The amount of distributional data is very uneven across the different biological groups, and unrelated to the diversity they possess. The global patterns of completeness seem to be conditioned by the historical taxonomic, faunistic and floristic interest received by the different classes of organisms. In addition, well-surveyed global areas account for barely 1 % of global climate variability, leaving uncovered a large set of climatic conditions. All these results prevent us from relying exclusively on the available primary information on the distribution of organisms to identify biodiversity patterns and/or design conservation proposals. Given that the biodiversity crisis demands urgent action, biases and gaps in primary biodiversity information cannot be an excuse and conservation decisions must be made considering a broad set of criteria based on existing scientifically proven knowledge and techniques capable of providing the necessary answers.

Protected areas are threatened by an unprecedented intensification of land use. The effectiveness of protected areas depends on their ability to stop habitat loss not only within their boundaries but also in their surroundings. Based on the CORINE Land Cover data, we describe the land use-land cover changes in European National Parks, both inside and at distant surrounding areas (1, 5, 20 km), and examine if the detected pattern is homogeneous across Europe. We analysed 192 parks from 25 European countries using five temporal scenarios between 1986 and 2018. Our results indicate that the designation of a protected area is a process that can increase it's the area's natural condition in a few years, thus providing a beneficial effect on its surrounding environment. However, this effect depends on the distance and when the protected area was declared. The naturalization effect is more visible at the nearest buffer distances in reserves that have been protected for the longest time. Furthermore, the role played by protected areas shows a spatially heterogeneous distribution, with clear notable latitudinal differences. In essence, these results are fundamental for developing effective adaptation strategies and proposing better policies to protect European NPs.

Species distribution models (SDM) are widely used as indicators of different aspects of geographical ranges for many purposes, from conservation to biogeographical and evolutionary analyses. However, these techniques are susceptible to various sources of uncertainty. Data coverage, species’ ecology, and the characteristics of their geographic distributions can affect SDM results, often generating critical errors in predicted distribution maps. We assess the influence of data quality, the characteristics of species distributions, and ecological traits on SDM performance. We predict the distributions of dung beetle species in Madrid region (central Spain) using six SDM techniques and validate them on an independent dataset. We relate variations in model performance with environmental completeness, data characteristics, and species traits through a partial least squares analysis. In this analysis, body size, nesting behaviour, marginality, rarity, data prevalence, Relative Occurrence Area (ROA), range size, niche breadth, and completeness are used as predictors of six assessment metrics (sensitivity, specificity, kappa, TSS, CCR, and AUC). Marginality and data prevalence were the variables that most influenced SDM performance, followed by range size, ROA, and niche breadth: species presenting higher marginality and data prevalence, and smaller ROA and niche breadth were associated with better models. Nesting behaviour, rarity, niche completeness, and body size had minor importance for SDM performance. Our results highlight the importance of taking species’ and data characteristics into account when modelling and comparing large groups of species using SDM. This implies that estimates of species richness and composition based on stacked SDMs can show high levels of error if they are constructed for groups of species with diverse ecological traits and types of geographic distributions. We suggest that the species holding characteristics that lead to poor SDM performance

Beetles are the most successful and diversified animal taxa characterized by the possession of an external pair of sclerotized wings (elytra). Managing electromagnetic radiations could be one of the functions of the exoskeleton. We studied the spectrophotometric response to ultraviolet, visible, and near-infrared radiations of the elytra of seven closely related and sympatric Onthophagus species to examine if the environmental preferences of these species could be associated with the spectrophotometric behaviour of their elytra. Our results indicated that sibling species can drastically differ in their environmental preferences but not in their spectrophotometric responses. However, our results corroborated that there are interspecific differences in the spectrophotometric characteristics of the elytra, which are mainly explained by morphological features. Among the examined morphological variables, darkness seems to be especially relevant as it facilitates the absorbance and obstructs the transmittance of visible and near-infrared radiations.

There is consensus surrounding the need to include a third dimension when estimating Species Distribution Models (SDMs), which is of special interest for marine species. Application of the third dimension is, however, rarely available, thus users are obliged to manually combine 2D SDM outputs (i.e., suitability or presence/absence maps) for 3D distribution generation. Herein, the Niche of Occurrence 3D (NOO3D) is presented, which is a new, simple modelling procedure that provides 3D distributions using both 3D occurrence samples and environmental datasets that consist of one layer per depth value. NOO3D performance was evaluated using five virtual marine species to avoid errors associated with real data sets (three pelagic species, with wide, medium, and narrow distributions, respectively, a mesopelagic species and an abyssal species). These virtual species are distributed across the North Atlantic Ocean and were built to a 0.5° x 0.5° resolution and considering 49 depth levels (from 0.43 m to an undersea depth of 5274.7 m). NOO3D results were also compared to those provided by 3D Alpha Shapes and Maximum Entropy (MaxEnt). The True Positive Rate (TPR), or sensitivity, True Negative Rate (TNR), or specificity, False Positive Rate (FPR), or commission error, and False Negative Rate (FNR), or omission error, were employed in order to facilitate comparison between methods. MaxEnt performed best for TPR, TSS and FNR, and Alpha Shape 3D performed best for FPR and TNR. NOO3D was always the second-ranked method for all metrics considered, which indicates that it was the most suitable method. The provided results indicate that NOO3D can be considered a viable alternative in achieving three-dimensional species distribution models.

Ivermectin is the most common endectocide used to control parasites affecting livestock. Short-term physiological and behavioural effects of ivermectin on dung beetles may have long-term consequences for beetle populations and ecosystem functioning. Long-term effects of the use of ivermectin can be estimated by comparing dung assemblages and ecosystem functions in areas with conventional ivermectin-treated livestock and environmentally similar areas in which livestock are not treated with veterinary medical products (organic farming). In this study, we investigated both short-term and long-term effects of the administration of ivermectin on the characteristics of dung beetle assemblages and the services they provided in a protected area (Doñana National Park, SW Spain). We examined short-term dung colonization, dwelling, relocation, and disaggregation rates and the associations between these processes and the key assemblage parameters of species richness, abundance, biomass and functional diversity. Furthermore, we analysed changes in soil physical-chemical properties and processes. Short-term differences were observed in the total amount of dung relocated by dung beetles at different colonization vs. emigration stages, suggesting that dung beetles in this area were affected by the recent treatments of livestock with ivermectin. Moreover, short-term effects could also be responsible for the significant differences in dung spreading rates between sites. Conventional use of ivermectin disrupted ecosystem functioning by affecting species richness, abundance and biomass. The decrease in diversity parameters was related to a reduction in the functional efficiency, which resulted in the long-term accumulation of dung on the ground and considerable changes in soil functionality.

Insects can use thermoregulation to keep their body temperatures within a certain range in response to thermal stress situations. The mechanisms to regulate internal temperature depend on whether species are endothermic or ectothermic species, i.e., if the heat source is internal and/or external. In this study, the thermal stress response due to excess heat was examined in individuals belonging to different species of the Geotrupinae subfamily by using a standardized protocol based on infrared thermography. All the measured heat stress variables allow discrimination among the considered species to a greater or lesser extent. The body heating rate in the heat stress range, the critical thermal maximum and the stress start temperature were the most important variables in discriminating between apterous and winged individuals (R2 = 52.5%, 51.1% and 50.0%, respectively). Examining the degree of association between the physiological similarity of individuals and some species traits suggest that flying capability and daily activity are related with different thermal responses. Based on the obtained results, the Geotrupinae subfamily can be divided into three ecophysiological groups: good, medium and non-thermoregulators. Within these groups, apterism appears mainly in those species with the ability to actively decrease their body temperature. Our results indicate that this ability may be partially due to the management of water loss related with evaporative cooling.

Insects can use thermoregulation to keep their body temperatures within a certain range in response to thermal stress situations. The mechanisms to regulate internal temperature depend on whether species are endothermic or ectothermic species, i.e., if the heat source is internal and/or external. In this study, the thermal stress response due to excess heat was examined in individuals belonging to different species of the Geotrupinae subfamily by using a standardized protocol based on infrared thermography. All the measured heat stress variables allow discrimination among the considered species to a greater or lesser extent. The body heating rate in the heat stress range, the critical thermal maximum and the stress start temperature were the most important variables in discriminating between apterous and winged individuals (R2 = 52.5%, 51.1% and 50.0%, respectively). Examining the degree of association between the physiological similarity of individuals and some species traits suggest that flying capability and daily activity are related with different thermal responses. Based on the obtained results, the Geotrupinae subfamily can be divided into three ecophysiological groups: good, medium and non-thermoregulators. Within these groups, apterism appears mainly in those species with the ability to actively decrease their body temperature. Our results indicate that this ability may be partially due to the management of water loss related with evaporative cooling.

Understanding the spatial distribution of elephant carcasses in relation to ecological characteristics and human activities is critical to developing targeted management strategies for reducing poaching. We employ a spatial modelling approach to quantify the relative contribution of multiple climatic, ecological, human and protected area management predictors of the number of elephant carcasses in a recognized poaching hotspot: the Ruvuma landscape of northern Mozambique and southern Tanzania. This includes the Niassa Reserve in the south and the Selous Game Reserve in the north. In Mozambique, the number of elephant carcasses is positively associated with State-managed protected areas such as Niassa Reserve, but particularly with environmental variables including low rainfall and high temperatures. In Tanzania, elephant carcasses are positively associated with community-managed sites. A strong focus on effective management of protected areas in the Ruvuma landscape is crucial to reducing the killing of elephants.

Biodiversity databases are typically incomplete and biased. We identify their three main limitations for characterizing the geographic distributions of species: unknown levels of survey effort, unknown absences of a species from a region, and unknown level of repeated occurrence of a species in different samples collected at the same location. These limitations hinder our ability to distinguish between the actual absence of a species at a given location and its (erroneous) apparent absence as consequence of inadequate surveys. Good practice in biodiversity research requires knowledge of the number, location and degree of completeness of relatively well-surveyed inventories within territorial units. We herein present KnowBR, an application designed to simultaneously estimate the completeness of species inventories across an unlimited number of spatial units and different geographical extents, resolutions and unit expanses from any biodiversity database. We use the number of database records gathered in a territorial unit as a surrogate of survey effort, assuming that such number correlates positively with the probability of recording a species within such area. Consequently, KnowBR uses a “record-by-species” matrix to estimate the relationship between the accumulated number of species and the number of database records to characterize the degree of completeness of the surveys. The final slope of the species accumulation curves and completeness percentages are used to discriminate and map well-surveyed territorial units according to user criteria. The capacity and possibilities of KnowBR are demonstrated through two examples derived from data of varying geographic extent and numbers of records. Further, we identify the main advances that would improve the current functionality of KnowBR.

Ivermectin is the most common endectocide used to control parasites affecting livestock. Short-term physiological and behavioural effects of ivermectin on dung beetles may have long-term consequences for beetle populations and ecosystem functioning. Long-term effects of the use of ivermectin can be estimated by comparing dung assemblages and ecosystem functions in areas with conventional ivermectin-treated livestock and environmentally similar areas in which livestock are not treated with veterinary medical products (organic farming). In this study, we investigated both short-term and long-term effects of the administration of ivermectin on the characteristics of dung beetle assemblages and the services they provided in a protected area (Doñana National Park, SW Spain). We examined short-term dung colonization, dwelling, relocation, and disaggregation rates and the associations between these processes and the key assemblage parameters of species richness, abundance, biomass and functional diversity. Furthermore, we analysed changes in soil physical-chemical properties and processes. Short-term differences were observed in the total amount of dung relocated by dung beetles at different colonization vs. emigration stages, suggesting that dung beetles in this area were affected by the recent treatments of livestock with ivermectin. Moreover, short-term effects could also be responsible for the significant differences in dung spreading rates between sites. Conventional use of ivermectin disrupted ecosystem functioning by affecting species richness, abundance and biomass. The decrease in diversity parameters was related to a reduction in the functional efficiency, which resulted in the long-term accumulation of dung on the ground and considerable changes in soil functionality.

Experimental information on the roles played by climatic factors in determining the ecology and distribution of insect species is scarce. This has stimulated the increasing use of the climatic characteristics of the localities in which the species are observed to derive predictions under different climatic scenarios (the so called species-distribution models or SDMs). This text reviews the main limitations of these correlative models when they are applied to organisms, such as insects, that are characterized by a high degree of collector bias and incompleteness. It is argued that SDMs must rely solely on presence information, rejecting the use of background or pseudoabsences, and that we are not predicting the future distribution of a species but exploring the future location of the climatic conditions in which a species was observed. The scarcity and bias of the available occurrence information in insects as well as our ignorance about the non-climatic factors delimiting species ranges forces us to be extremely careful. It is therefore desirable to avoid the use of central tendency measures reflecting supposed optimum niche conditions because they are particularly dependent on the quantity and biases of the occurrence information. The use of simple algorithms and procedures aimed at extracting information on environmental limits from the available occurrences would be more convenient in this case.

The study of insect responses to thermal stress has involved a variety of protocols and methodologies that hamper the ability to compare results between studies. For that reason, the development of a protocol to standardize thermal assays is necessary. In this sense, infrared thermography solves some of the problems allowing us to take continuous temperature measurements without handling the individuals, an important fact in cold-blooded organisms like insects. Here, we present a working protocol based on infrared thermography to estimate both cold and heat thermal stress in insects. We analyse both the change in the body temperature of individuals and their behavioural response. In addition, we used partial least squares regression for the statistical analysis of our data, a technique that solves the problem of having a large number of variables and few individuals, allowing us to work with rare or endemic species. To test our protocol, we chose two species of congeneric, narrowly distributed dung beetles that are endemic to the southeastern part of the Iberian Peninsula. With our protocol we have obtained five variables in the response to cold and twelve in the response to heat. With this methodology we discriminate between the two flightless species of Jekelius through their thermal response. In response to cold, Jekelius hernandezi showed a higher rate of cooling and reached higher temperatures of stupor and haemolymph freezing than Jekelius punctatolineatus. Both species displayed similar thermoregulation ranges before reaching lethal body temperature with heat stress. Overall, we have demonstrated that infrared thermography is a suitable method to assess insect thermal responses with a high degree of sensitivity, allowing for the discrimination between closely related species.

The study of insect responses to thermal stress has involved a variety of protocols and methodologies that hamper the ability to compare results between studies. For that reason, the development of a protocol to standardize thermal assays is necessary. In this sense, infrared thermography solves some of the problems allowing us to take continuous temperature measurements without handling the individuals, an important fact in cold-blooded organisms like insects. Here, we present a working protocol based on infrared thermography to estimate both cold and heat thermal stress in insects. We analyse both the change in the body temperature of individuals and their behavioural response. In addition, we used partial least squares regression for the statistical analysis of our data, a technique that solves the problem of having a large number of variables and few individuals, allowing us to work with rare or endemic species. To test our protocol, we chose two species of congeneric, narrowly distributed dung beetles that are endemic to the southeastern part of the Iberian Peninsula. With our protocol we have obtained five variables in the response to cold and twelve in the response to heat. With this methodology we discriminate between the two flightless species of Jekelius through their thermal response. In response to cold, Jekelius hernandezi showed a higher rate of cooling and reached higher temperatures of stupor and haemolymph freezing than Jekelius punctatolineatus. Both species displayed similar thermoregulation ranges before reaching lethal body temperature with heat stress. Overall, we have demonstrated that infrared thermography is a suitable method to assess insect thermal responses with a high degree of sensitivity, allowing for the discrimination between closely related species. 2016 Elsevier Ltd. All rights reserved

The establishment of protected areas is one of the main strategies to reduce losses of biodiversity. While a number of studies have evaluated the effectiveness of existing reserves in preserving representative samples of ecosystem and species diversity, there has been no systematic assessment of their effectiveness in terms of conserving evolutionary history. We used comprehensive phylogenies of four lineages of aquatic Coleoptera to investigate (i) the performance of National Parks (NPs) in representing the phylogenetic diversity (PD) of the Iberian Peninsula; (ii) the representation in NPs of the species with the highest conservation priority, as identified from a combination of their evolutionary distinctiveness and vulnerability; and (iii) whether species richness may be a good surrogate of PD when selecting new conservation areas. Our results show that Iberian NPs perform poorly in the preservation of freshwater PD. In most cases PD was not different from a random expectation, but when it did differ, PD in NPs was always lower than that obtained by a random selection of the same number of species. We also found that most of the highly evolutionarily distinct and vulnerable taxa were not covered by any NP. Finally, when additional conservation areas were selected maximizing the number of unrepresented species, the variation in PD could be very high, and as a consequence, depending on the group and the number of areas added, they could preserve much less evolutionary history than when they were specifically selected to maximize PD. © 2013 Elsevier Ltd.

This article examines the role of the Late Pleistocene climatic changes in the disappearance of the European populations of spotted hyenas. A species distribution model was built using both current and past environmental requirements of the species. Model projections were made with climatic scenarios provided by the GENESIS 2.0 General Circulation Model (126 ka, 42 ka, 30 ka and 21 ka). Those projections indicate (1) that during the Late Pleistocene warm scenarios spotted hyenas should have been widespread in Europe, and (2) that during the last glacial maximum their potential climatically suitable geographic distribution diminished in size. The decrease in the potential climatic distribution was strictly restricted to Northern Europe. Climatic conditions in Southern Europe during the Late Pleistocene remained within the spotted hyena climatic tolerance. Hence, climate changes could have directly affected the Northern distribution of the species during the last glaciations. However, climate change alone is not sufficient to have caused the disappearance of the spotted hyena populations in Southern Europe. That is, other factors, such as prey abundance or human ecological impacts, in addition to climatic change, are needed to completely account for extinction of the European spotted hyena.

Although the conversion of natural vegetation to agriculture threatens biodiversity, post-agricultural lands may provide an opportunity to preserve biodiversity if they are allowed to regenerate. We develop a framework for incorporating abandoned agricultural fields into the design of a Biosphere Reserve using former cocoa plantations on Bioko, Equatorial Guinea, as a case study. First, we used BIOCLIM to model the potential distribution of 62 ferns, 327 monocotyledons, 749 dicotyledons, seven primates, and 104 birds on Bioko. Next, we quantitatively assessed the representation of these distributions in conservation areas proposed by the Equatoguinean administration (hereafter “EPAs”). In addition, we used an area prioritization algorithm implemented in the ResNet software package to select an initial set of sites to serve as the Biosphere Reserve’s core areas, that is, intact forest in Bioko’s montane regions. Then, to augment the beta-diversity of the Reserve, we used the area prioritization algorithm to prioritize buffer zones in lowland sites including rainforest remnants and abandoned plantations that have partially regenerated to forest. We also compared the representation of biodiversity in the EPAs to its representation in Biosphere Reserves designed with ResNet. The representation of vegetation types and species in Reserves selected by ResNet that occupy 25% of the land on Bioko is equivalent to the representation achieved by the EPAs, which would cover 42% of Bioko. To conclude, we propose a conservation plan for Bioko.

We examine the potential for two species – the wild rabbit Oryctolagus cuniculus and the dung beetle Thorectes valencianus – to affect the establishment of Erodium praecox, an endemic plant of the Iberian Peninsula. Rabbit latrines may be considered potential maternal parent areas of E. praecox. The spatial and temporal stability for nutrients and surface irregularities caused by the activity of rabbits increases bare soil areas. A negative relation between diameter of the basal rosettes of Erodium and the distance to the centroid of latrines was observed. Rabbit latrines were important for E. praecox distribution but their effect was higher when T. valencianus burrows exist. In laboratory conditions, a higher number of seeds buried was observed in latrines with dung beetles, while a lower number of seeds buried was observed in bare soil. T. valencianus activity plays the role of a soil fertilizer, increasing the rate of nutrient cycling and microbial activity which could raise the rate of decomposition of pellets and result in the further release of nutrients. The excavation of the dung beetles increases the soil fertilization and the surface irregularities required for the seeds of E. praecox to be easily self-buried.

Even though singing plays a major role in bird communication, environmental variables affecting the geographic patterns observed in the variation of singing onset within large areas have not previously been studied. The singing phenology of two long-distance migrants, the Cuckoo Cuculus canorus and the Nightingale Luscinia megarhynchos, recorded in thousands of sites throughout Spain, was related to a set of 51 explanatory variables by partial least squares regression. Observed variability in singing onset among localities follows spatial trends on an Iberian scale at 10 10 km resolution, and was well modelled by some environmental variables. Of these variables, climate was the most influential. Males of both species sang earlier in warmer and drier sites. Males who were near the Straits of Gibraltar and in the southern Iberian basins, which are geographic gradients closely related with climate in the Iberian Peninsula, were also heard earlier. Most environmental variables affected the singing activity of both species equally, i.e., the same environmental gradients are linked to singing onset. However, the models’ predictions indicated differences in the geographical pattern in singing onset between both species, mainly related to their rates of progression during spring migration through Spain. Local variables, such as land uses, vegetation productivity or species abundance, played a minor role on singing onset spatial patterns. Therefore, models’ composition supports the hypothesis that singing onset is a good proxy of arrival dates in migratory species, since those variables related to indirect effects on singing onset phenology through migratory progression and arrival to the breeding grounds showed the highest influence.

In contrast to the attention attracted by temporal trends of phenology, the spatial patterns of arrivals, departures or stays of trans-Saharan birds are still nowadays largely unknown in most of their European breeding areas. In the case of the white stork (Ciconia ciconia), some studies have attempted to describe its migratory patterns throughout some European countries but, to our knowledge, no one has related these patterns to some kind of explanatory variable which offers an ecologically-based explanation for the heterogeneous phenology observable among populations. Here, arrivals, departures and stays of this species, recorded in hundreds of Spanish localities, were related to a set of environmental, geographical, biological and spatial predictors, and modeled by multiple regression. The best model for arrival dates accounted for up to 34% of variability of data and pointed towards an earlier arrival in those populations located in south-western Iberia and with higher population densities. This last relationship is probably due to the competition for nest-site fidelity maintenance. However, no variable was able to explain properly the blurred spatial pattern recorded for departure dates. Departure decisions are strongly influenced by social behavior in this species and depend on collective decisions influenced by peculiar local environmental conditions of each year rather than macrogeographical gradients. Environmental, geographical or spatial variables also did not capture much of the observed variability in the length of the stays among populations. However, this variable was strongly related to the arrival and departure dates of populations. White storks stay longer in localities with earlier arrivals and, especially, later departures.

Processes of seed predation and dispersal are crucial for tree regeneration and forest dynamics. To understand the role of the dung beetle, Thorectes lusitanicus (Col., Scarabaeoidea, Geotrupidae) as secondary seed disperser in Mediterranean oak forests, its food preference was investigated in the field and in the laboratory. This paper had for objectives (1) to explore the feeding preferences for acorns of the two species available in the field: Quercus suber and Quercus canariensis, and (2) to study the olfactory and palatability response of T. lusitanicus to different food resources (oak acorns and dung) under laboratory conditions. The number of beetles in the field was curvilinearly related to the number of acorns, being higher when the number of acorns was intermediate. The maximum values of T. lusitanicus density corresponded to those plots located under Q. suber trees with the highest total weight of acorns. Bioassays with a fourarmed olfactometer showed that T. lusitanicus was clearly attracted to volatiles of Q. suber acorns more than to of dung. Palatability bioassays also showed significant preferences for acorns of Q. suber in comparison with the typical food previously described for this beetle species (dung). According to our results, we suggest that a diet based on acorns (due to their high content of polyunsaturated fatty acids) probably satisfies the nutritional requirements of T. lusitanicus during winter, larval development, and metamorphosis.