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In the Northern Alboran Sea, artisanal small-scale fisheries using trammel nets suffer economic losses, and local fishermen see their way-of-life endangered, due to interactions with wildlife species such as alien species and dolphins. On the one hand, the alien seaweed Rugulopteryx okamurae, which was first recorded in the Alboran Sea in 2015, has undergone an intensive expansion in the sub-region, monopolizing the available seabed, causing radical changes in the underwater seascape and clogging the trammel nets. On the other hand, the damage caused to the fishing nets by dolphin fish predation is an ancient problem worldwide, but it is intensifying in the last years. The main objective of this study is to understand the main environmental and technical conditions that favor damages of fishing trammel nets in the Alboran Sea, which entails an important loss of catchability, due to (i) the clogging of the artisanal fishing trammel nets by invasive seaweed, and (ii) the breaking of the nets by dolphin predation. Through close monitoring of fishermen in port, we obtained direct information of 548 sets. Our results indicate that approximately 30% of trammel sets suffered a damage due to unwanted interaction with alien seaweeds and dolphins. As seaweeds invasion is a global problem while dolphin-fishing gear interaction is more local, we concluded that only a large-scale management of exotic algae, together with the involvement of local fishermen, could solve the economic problems of this activity. [ABSTRACT FROM AUTHOR]

Deep-habitat cetaceans are generally difficult to study, leading to a limited knowledge of their population. This paper assesses the differential distribution patterns of three deep-habitat cetaceans (Sperm whale—Physeter macrocephalus, Risso's dolphin—Grampus griseus & Cuvier's beaked whale—Ziphius cavirostris). We used data of 842 opportunistic sightings of cetaceans in the western Mediterranean sea. We inferred environmental and spatio-temporal factors that affect their distribution. Binary logistic regression models were generated to compare the presence of deep-habitat cetaceans with the presence of other cetacean species in the dataset. Then, the favourability function was applied, allowing for comparison between all the models. Sperm whale and Risso's dolphin presence was differentially favoured by the distance to towns in the eastern part of the western Mediterranean sea. The differential distribution of sperm whale was also influenced by the stability of SST, and that of the Risso's dolphin by lower mean salinity and higher mean Chlorophyll A concentration. When modelling the three deep-habitat cetaceans (including Cuvier's beaked whale), the variable distance to towns had a negative influence on the presence of any of them more than it did to other cetaceans, being more favourable far from towns, so this issue should be further investigated. [ABSTRACT FROM AUTHOR]

Yellow fever is transmitted by mosquitoes among human and non-human primates. In the last decades, infections are occurring in areas that had been free from yellow fever for decades, probably as a consequence of the rapid spread of mosquito vectors, and of the virus evolutionary dynamic in which non-human primates are involved. This research is a pathogeographic assessment of where enzootic cycles, based on primate assemblages, could be amplifying the risk of yellow fever infections, in the context of spatial changes shown by the disease since the late 20th century. In South America, the most relevant spread of disease cases affects parts of the Amazon basin and a wide area of southern Brazil, where forest fragmentation could be activating enzootic cycles next to urban areas. In Africa, yellow fever transmission is apparently spreading from the west of the continent, and primates could be contributing to this in savannas around rainforests. Our results are useful for identifying new areas that should be prioritised for vaccination, and suggest the need of deep yellow fever surveillance in primates of South America and Africa. Models based on primates and disease vectors indicate a risk of zoonotic and anthroponotic yellow fever expansion in South America and Africa. [ABSTRACT FROM AUTHOR]

The North Atlantic Oscillation (NAO) is the most important large-scale climatic oscillation affecting the North Atlantic region. The variability introduced by the NAO affects many meteorological parameters, including wind speed and direction, and differences in air temperature and rainfall, particularly during the boreal winter. The NAO is also known to affect the ocean by changing heat content, sea surface temperature, gyre circulation, mixed layer depth, salinity, high-latitude deep water formation, and sea ice cover. Consequently, the NAO has been widely used to analyze the variability of marine ecosystems. Several researchers found that fishery resources were teleconnected with the NAO variability, resulting in a significant relationship between this climatic oscillation and fishery yields. More precisely, the NAO affects the target species abundance, recruitment, catchability, and body condition. These effects can be cumulative over time and act synergistically. In this study, the available information about this topic is reviewed, and the importance of the NAO as a large-scale climatic oscillation in fisheries management is discussed using an ecosystem approach. We also discuss the possible effects of climate change on Atlantic and Mediterranean fisheries if this change were to affect the NAO pattern. [ABSTRACT FROM AUTHOR]

Currently, there are naturalized populations of feral pigeon (Columba livia var. domestica) worldwide with an estimated global population between 165 and 330 million individuals. Feral pigeons are adapted to urban environments, creating problems related to human health, damage to architectural structures, unpleasant soiling, and foul odors. Thus, local governments usually implement measures to reduce feral pigeon populations in cities to a suitable size. We monitored a feral pigeon trapping campaign to investigate the use of cage traps as control method in residential zones. We analyzed efficiency (daily capture rate), effectiveness (defined as the number of feral pigeons captured relative to the total number of potential pigeon captures), animal welfare, selectivity (the proportion of captured feral pigeons in relation to the total number of captured animals), and the effect on feral pigeon abundance. All procedures were conducted in compliance with current European and Spanish legislation. Overall efficiency was 0.25 feral pigeons/trap-day, effectiveness was 22.5%, and selectivity was 99.7%. Over the study period, there was a decreasing trend in abundances. A significant decrease was found in the relative abundances of feral pigeons after 2 months of extractions, and population abundances remained low up to the end of the extraction period. The use of cage traps was a useful and effective method to reduce local feral pigeon populations in isolated urban areas with low building density in which the feral pigeon population has not yet reached high densities. [ABSTRACT FROM AUTHOR]

Monitoring progress towards global goals and biodiversity targets require reliable descriptions of species distributions over time and space. Current gaps in accessible information on species distributions urges the need for integrating all available data and knowledge sources, and intensifying cooperations to more effectively support global environmental governance. For many areas and species groups, experts can constitute a valuable source of information to fill the gaps by offering their knowledge on species-environment interactions. However, expert knowledge is always subject to uncertainty, and incorporating that into species distribution mapping poses a challenge. We propose the use of the dempster-shafer theory of evidence (DST) as a novel approach in this field to extract expert knowledge, to incorporate the associated uncertainty into the procedure, and to produce reliable species distribution maps. We applied DST to model the distribution of two species of eagle in Spain. We invited experts to fill in an online questionnaire and express their beliefs on the habitat of the species by assigning probability values for given environmental variables, along with their confidence in expressing the beliefs. We then calculated evidential functions, and combined them using Dempster's rules of combination to map the species distribution based on the experts' knowledge. We evaluated the performances of our proposed approach using the atlas of Spanish breeding birds as an independent test dataset, and further compared the results with the outcome of an ensemble of conventional SDMs. Purely based on expert knowledge, the DST approach yielded similar results as the data driven SDMs ensemble. Our proposed approach offers a strong and practical alternative for species distribution modelling when species occurrence data are not accessible, or reliable, or both. The particular strengths of the proposed approach are that it explicitly accounts for and aggregates knowledge uncertainty, and it capitalizes on the range of data sources usually considered by an expert. [ABSTRACT FROM AUTHOR]

Ebola virus disease (EVD) is a contagious, severe and often lethal form of hemorrhagic fever in humans. The association of EVD outbreaks with forest clearance has been suggested previously but many aspects remained uncharacterized. We used remote sensing techniques to investigate the association between deforestation in time and space, with EVD outbreaks in Central and West Africa. Favorability modeling, centered on 27 EVD outbreak sites and 280 comparable control sites, revealed that outbreaks located along the limits of the rainforest biome were significantly associated with forest losses within the previous 2 years. This association was strongest for closed forests (>83%), both intact and disturbed, of a range of tree heights (5–>19 m). Our results suggest that the increased probability of an EVD outbreak occurring in a site is linked to recent deforestation events, and that preventing the loss of forests could reduce the likelihood of future outbreaks. [ABSTRACT FROM AUTHOR]

An accurate estimation of the expected consequences of climate change requires the proper quantification of the effect of climate on current species distributions. Several interrelated sources of uncertainty may affect the likelihood of species distribution models (SDMs) to determine the relative importance of climate. Our aim was to assess the relationship between the influence of geographical background (GB) delimitation and that of subtracting the non-climate effects from the weight of climatic predictors to estimate the combined influence of these two factors on predictions in climate change scenarios. The distribution of 40 endemic mammals in Western Europe have been modeled by (i) using the whole territory of Western Europe as the GB and also specifically delimiting the GB with a geographical criterion and (ii) considering climatic predictors in addition to other non-climatic variables in order to extract the pure effect of climate. The models were used to quantify species' sensitivity to new climate scenarios. Results showed discrepancies among the analytical approaches. Changes in distribution obtained by considering the pure effect of climate were lower than those obtained by considering the apparent effect, and GB-delimited models yielded higher changes than those trained in Western Europe. We evidence that climate weighting and GB delimitation have dramatic influences on the projections of models when transferred to new scenarios. We emphasize that scientific studies and derived adaptation policies based on SDMs without an explicit consideration of the GB and the weighting of the climate-related variables may be misleading and in need of revision. [ABSTRACT FROM AUTHOR]

We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met. [ABSTRACT FROM AUTHOR]

Placobdella costata is a leech specific to freshwater turtle Emys orbicularis. Both genera are native to North America and have co-evolved and undergone dispersion through the Palearctic. The leech is present throughout the Mediterranean area, always associated with E. orbicularis. Their only known presence in the Iberian Peninsula is in the north and center of the peninsula. Here we present the first description of the leech in southern Spain (Andalusia) in association with a small fragmented population of fresh-water turtles in which E. orbicularis and Mauremys leprosa coexist. Unusually, the leech was found attached to the carapace of a male M. leprosa. [ABSTRACT FROM AUTHOR]

Cory's shearwater Calonectris diomedea is the main seabird species by-caught by the Spanish longline fleet operating in the western Mediterranean Sea. Identification of the principal factors that determine this by-catch and understanding how they could be controlled is fundamental for improving the management of fisheries and so carry out a better conservation of Cory's shearwater populations in the Mediterranean. The aim of this paper was to model the longline by-catch of Mediterranean Cory's shearwater in the Spanish Mediterranean longline fishery as a function of time of the year, technical characteristics of the fishing operation, and geographical location. We used data recorded by an onboard observer program monitoring commercial longline fisheries. During the 10 years covered in this study, 80 birds were captured in 30 fishing operations out of a total of 2,587 observed fishing sets. We used favourability functions and Random Forest analyses to relate the presence of Cory's shearwater in the by-catch with the explanatory factors. The most explanatory factor in relation to incidence of by-catch was the geographical location (longitude and fishing over the continental shelf) and then the technical characteristics of the fishing operation (number of hooks and fishing during non-working days). Our conclusion is clear, because seabirds are more likely to approach longline vessels when trawlers are not allowed to operate (i.e. non-working days), activity of longliners should be limited to working days, and closing longliners activity during the month of October could reduce greatly reducing seabird bycatch. [ABSTRACT FROM AUTHOR]

This study explores the possible effects of the North Atlantic Oscillation (NAO) on the quality of Spanish Cava. We found a significant negative relationship between the mean NAO for the months of March through August of each year between 1970 and 2008 and the probability of obtaining a top quality Cava. The NAO is associated with temperature and rainfall variations in the Cava region, which affect vine physiological processes during grape maturity. The probability of obtaining a top quality Cava was highest when the mean value of the NAO was negative, which causes the mean temperature in the Cava area to decrease, with positive consequences on Cava quality. Although the overall discrimination capacity and explanatory power of the model were low, 80 % of clearly favorable years were classified correctly as corresponding to top quality Cava, and 70 % of clearly unfavorable years were classified correctly as non top quality Cava. [ABSTRACT FROM AUTHOR]

The idea of analysing the general favourability for the occurrence of an event was presented in 2006 through a mathematical function. However, even when favourability has been used in species distribution modelling, the conceptual framework of this function is not yet well perceived among many researchers. The present paper is conceived for providing a wider and more in-depth presentation of the idea of favourability; concretely, we aimed to clarify both the concept and the main distinctive characteristics of the favourability function, especially in relation to probability and suitability, the most common outputs in species distribution modelling. As the capabilities of the favourability function go beyond species distribution modelling, we also illustrate its usefulness for different research disciplines for which this function remains unknown. In particular, we stressed that the favourability function has potential to be applied in all the cases where the probability of occurrence of an event is analysed, such as, for example, habitat selection or epidemiological studies. [ABSTRACT FROM AUTHOR]

Hyperpredation can be described as a restrictive case of apparent competition where an increased number of primary prey species indirectly induces the decrease of the secondary prey species through numerical response of predators to the primary prey dynamics. It has been proposed that rabbit hemorrhagic disease (RHD), which decimated populations of European wild rabbit (Oryctolagus cuniculus) in Spain, led to prey switching by raptors towards red-legged partridges (Alectoris rufa) causing declines in their populations as a peculiar case of hyperpredation. We have reviewed field studies that disagree with estimates (based on bag records) of recent increases of rabbit and partridge numbers in Spain. Because of an increase in releases of farm-reared animals, there is doubt about the use of bag records to accurately estimate population trends in recent decades. We also provide new data and discuss some analytical considerations related to the temporal and spatial scales that might affect the interpretation of data. Finally, we discuss why studies associated with raptor food habits, predator population dynamics and predator distribution suggest that diet data are not sufficient to link patterns and processes. Although we agree that the RHD outbreak has markedly affected rabbit populations, which has indirectly affected many other species in the Iberian Peninsula, we consider that hyperpredation mediated by raptors has not been clearly demonstrated. In contrast, endorsing the hypothesis of raptor-mediated hyperpredation without sufficient proof may have conflictive consequences if we consider the increased persecution of raptors in recent decades in Spain. [ABSTRACT FROM AUTHOR]

Some species are very difficult to observe in the wild, and some of these present an apparently incongruent distribution, as is the case of the spur-thighed tortoise Testudo graeca in the southern Iberian Peninsula. This species has a discontinuous distribution with two main reproductive areas: one in the contiguous provinces of Almeria and Murcia, and the other in Huelva province. Both populations are thought to maintain reproductive isolation. However, we present new records obtained from two areas (the provinces of Malaga and Cadiz) which are outside their previously known range. Malaga province and Cadiz province are located between the two traditional reproductive areas. The new records were based on 16 interviews with shepherds as well as information provided by three naturalists. The aim of this work was to analyze the spatial distribution of areas favourable to the spur-thighed tortoise in the southern Iberian Peninsula, using different models with the same group of variables but with a different number of records: known records, new records and a combination of them. We obtained a distribution model for the species in Andalusia consistent with all observations, which was related to climatic stability, climatic disturbances, and spatial situation. This model presented three main favourable areas: two are coincident with the two known nuclei, and the other is situated in the southern part of the region, in the contiguous provinces of Cadiz and Malaga. We conclude that it is important to consider all the observations in the distribution models because records outside the traditional reproductive areas can include other environmental characteristics appropriate for the species. [ABSTRACT FROM AUTHOR]

We tested two approaches to forecast species distributions while balancing the impact of climate change against the inertia promoted by other influential factors that have been forecast as not changing. Given that mountain species are presumed to be more at risk due to climate warming, we selected an amphibian, a reptile, a bird, and a mammal species present in the Spanish mountains, to model their distributional response to climate change during this century. The climatic forecasts were made according to the general circulation models CGCM2 and ECHAM4 and to the A2 and B2 emission scenarios. We modelled the response of the species to spatial, topographic, human, and climatic variables separately. In our first approach, we compared each of these single-factor models using the Akaike Information Criterion, and produced a combined model weighting each factor (spatial, topographic, human, and climatic) according to Akaike weights. This procedure overestimated the best model, and the other factors were neglected in the combined model output. In our second approach, we produced a combined model using stepwise selection of the variables previously selected within each factor. In this way every factor was effectively represented in the combined explanatory model of the distributional response of the species to environmental conditions. This enabled the construction of models that combined climate with the other explanatory factors, to be later extrapolated to the future by replacing current climatic and human values with those expected from each emission and socio-economic scenario, while preserving spatial and topographic variables in the model. [ABSTRACT FROM AUTHOR]

In recent decades, Mediterranean landscapes have been experiencing more rapid changes in land use than usual, which have affected the ecology of the species inhabiting this biodiversity hotspot. Some studies have assessed the effect of such changes on biodiversity, but most of these were diachronic studies of population dynamics, or synchronic studies of species habitat selection, whereas few studies have simultaneously taken into account temporal changes in habitat composition and changes in species distribution. This study analysed the effects of land-use changes on the distribution of wild ungulates ( Capreolus capreolus, Capra pyrenaica, Cervus elaphus and Sus scrofa). Using favourability function and Markov chain analysis combined with cellular automata, we addressed the following objectives: (i) to examine the environmental determinants of ungulate distribution in the past (1960s) and present (1990s), (ii) to model land use for 2040 to forecast future species distributions and (iii) to assess the biogeographical differences between the above-mentioned study periods (past-present and present-future). Species favourability was predicted to be more widely distributed in the present than in the past, but this increase varied across species. Areas predicted to be favourable in the present should remain stable in the future, but in addition there will be more new favourable areas not previously occupied by these species. The results are discussed from the perspective of the socio-economic relevance of wild ungulates in relation to some unfavourable areas of Mediterranean regions. [ABSTRACT FROM AUTHOR]

The Asian kelp Undaria pinnatifida was first reported in north-western Spain in 1988. Since then, it has spread along the Galician coasts and towards the western Cantrabrian coast, probably supported by new introductions related to aquaculture and private yachts. Despite the high potential of this seaweed to invade new areas, it has not fully established itself in specific areas along the eastern Cantabrian coast where it has been farmed. We attempted to identify the macro-environmental determinants for the successful establishment of U. pinnatifida in the northern Iberian coast. Thus, we built a model based on the significant relationships between this kelp and several environmental factors using the Favourability Function, a method based on binary logistic regression. We obtained a statistically significant Favourability model where the chlorophyll concentration in summer was the most influential variable and the photosynthetically active radiation in spring was a secondary variable that best characterized the presence of U. pinnatifida. The ecological implications are discussed. [ABSTRACT FROM AUTHOR]

In this study, we propose the use of a favourability function to perform Gap Analysis. To exemplify this, we modelled the distribution of terrestrial mammal species in Andalusia (South of Spain) on the basis of their presence/absence on a grid of 10 km 9 10 km UTM cells (n = 961). Using logistic regression and 30 variables related with the environment, space and human influence, we obtained probabilities of occurrence for each species in each cell. We computed a crisp favourability index considering the areas as favourable or unfavourable for a species if the probability of occurrence was higher or lower than the species prevalence, respectively. We also used a favourability function and fuzzy logic to level all species to the same threshold of favourability, which allowed to compare and to combine species distributions. Adding up the fuzzy favourability values for each species in each cell we obtained a fuzzy favourability index that we compared with species richness (sum of species in each cell) and with the crisp favourability index. We performed Gap Analysis by overlapping these results with the current reserve network of Andalusia. Gaps were grouped in fewer and bigger zones after applying the favourability indices. Considerations and recommendations for the use of the favourability function to select areas of conservation interest are discussed. [ABSTRACT FROM AUTHOR]

Logistic regression is a statistical tool widely used for predicting species’ potential distributions starting from presence/absence data and a set of independent variables. However, logistic regression equations compute probability values based not only on the values of the predictor variables but also on the relative proportion of presences and absences in the dataset, which does not adequately describe the environmental favourability for or against species presence. A few strategies have been used to circumvent this, but they usually imply an alteration of the original data or the discarding of potentially valuable information. We propose a way to obtain from logistic regression an environmental favourability function whose results are not affected by an uneven proportion of presences and absences. We tested the method on the distribution of virtual species in an imaginary territory. The favourability models yielded similar values regardless of the variation in the presence/absence ratio. We also illustrate with the example of the Pyrenean desman’s ( Galemys pyrenaicus) distribution in Spain. The favourability model yielded more realistic potential distribution maps than the logistic regression model. Favourability values can be regarded as the degree of membership of the fuzzy set of sites whose environmental conditions are favourable to the species, which enables applying the rules of fuzzy logic to distribution modelling. They also allow for direct comparisons between models for species with different presence/absence ratios in the study area. This makes them more useful to estimate the conservation value of areas, to design ecological corridors, or to select appropriate areas for species reintroductions. [ABSTRACT FROM AUTHOR]

Classification and ordination methods used to examine the internal complexity of the Mediterranean Tagus River catchment based on fish distribution revealed that it is not a homogeneous biogeographical unit. The indigenous fishes analyzed in this study are distributed through the basin forming geographical communities (chorotypes), some of which are associated with environmental factors like river morphology, water quality or geographical location. Nevertheless, 40% of the variation in species occurrence remains unexplained by either environmental or geographical variables, suggesting that historical factors may influence the freshwater fish distribution patterns. Three main biogeographical areas, delimited by significant boundaries, were identified. Two of them are identified as the upper and the middle-lower basins of the Tagus River catchment; the third corresponds to the Alagón River and seems to be linked to historical factors of the catchment. [ABSTRACT FROM AUTHOR]

The recent modification of species distribution ranges in response to a warmer climate has constituted a major and generalized biogeographic change. The main driver of the shift in distribution is the disequilibrium of the species ranges with their climatic favourability. Most species distribution modelling approaches assume equilibrium of the distribution with the environment, which hinders their applicability to the analysis of this change. Using fuzzy set theory we assessed the response to climate change of a historically African species, the Atlas Long-legged Buzzard. With this approach we were able to quantify that the Buzzard's distribution is in a latitudinal disequilibrium of the species distribution with the current climate of 4 km, which is driving the species range northwards at a speed of around 1.3 km/year, i.e., it takes 3 years for the species to occupy new climatically favourable areas. This speed is expected to decelerate to 0.5 km/year in 2060–2080. [ABSTRACT FROM AUTHOR]