Search

Simple Summary: In the Aragonese Pyrenees, we studied the survival and productivity of bearded vultures, an endangered species known for its diet of bones. Using data from 1987 to 2020, we found that the survival rates for juveniles, subadults and adults were 90%, 95% and 92%, respectively. Overall, the species' survival has improved, but juvenile survival is a concern. Productivity in the area is decreasing. Our research helps identify vulnerable age groups, guiding conservation efforts. The study suggests being cautious about feeding points to protect the species. The bearded vulture (Gypaetus barbatus) is an endangered species with a specialist osteophagous (bone) diet. We estimated the survival and productivity of this vulture in the Aragonese Pyrenees, where the main population of the species in Europe is found. We used a database covering a period of 33 years (1987–2020). To estimate the probability of survival, we used Cormack–Jolly–Seber models with a Bayesian approach. Our models estimated a survival rate of 0.90 ± 0.08 in juveniles, 0.95 ± 0.04 in subadults and 0.92 ± 0.05 in adults. The survival probability increased over the study period in adults and subadults but not in juveniles. By contrast, productivity decreased over the same period. Our study provides updated information on the status of two demographic parameters of great importance to the species and allows us to identify the most vulnerable age classes and to plan conservation actions to improve the situation of the species in a territory that is a donor of specimens for reintroduction projects. The estimated survival values suggest that more caution should be exercised when planning these feeding points according to the use the species makes of them. [ABSTRACT FROM AUTHOR]

• Roads are often used by agricultural pest species as dispersal corridors. • Rabbit damage to agricultural production has increased in Iberian Peninsula. • We assessed the distribution of rabbit warrens in motorway verges. • Rabbit warren presence correlated positively with the presence of olive groves. • Our modelling approach allows identifying high risk motorway stretches. Pest species cause significant ecological, social and economic impacts, and programs to control them usually target specific landscape features when pests use these to disperse. Roads or railways are often used by pest species as dispersal corridors, but little is known about the specific characteristics of these human infrastructures that facilitate pest species dispersal. This is particularly evident in the case of native agricultural vertebrate pests like the European wild rabbit (Oryctolagus cuniculu s) in the Iberian Peninsula (IP). Rabbit damage to agricultural production in IP has increased notably in recent years. This study uses a 'favourability function' to model the extent to which macroecological favourable conditions for rabbits and different fine-scale variables, including environmental, anthropogenic and agricultural factors, favour the presence of rabbit warrens on the verges of a motorway network in southern IP. For this purpose, we collected rabbit warren locations during car transects using CyberTraker 3.0 installed in a pad along 787 km of motorways. Our results revealed that rabbit warren distribution was widespread along the verges. Rabbit warren presence correlated positively with the presence of olive groves and with macroecological favourable conditions for rabbits. Our results provide strong evidence that rabbits use motorway verges, which are likely to act as dispersal corridors across landscapes. Additionally, our innovative approach, based on a rabbit warren index, the favourability function and a combination of local and macroecological predictors, could be used in many other areas where rabbits cause crop damage to make fine-scale predictions of high risk stretches and, therefore, where to apply mitigation measures. [ABSTRACT FROM AUTHOR]

The blue duiker ( Philantomba monticola) is an abundant and widely distributed ungulate in continental sub-Saharan Africa. High hunting pressure throughout its range may be particularly threatening to the persistence of island populations of the species. In this study, we assessed offtake of blue duikers in Pico Basilé, Bioko Island, Equatorial Guinea. We recorded the number of animals shot or snared by 46 commercial hunters over a 33-month period, and the location (elevation) of each animal hunted. From this, we estimated catch per hunter ( CH), catch per hunting day ( CD) and catch per unit effort ( CPUE). The number of duikers shot or snared across the study period, significantly declined within the mid-altitude range (901-1500 m). There were no significant drops in CH or CPUE at low or high altitudes for snared animals. The ratio of immature-to-adult animals hunted increased significantly over time within the mid-altitude range. We suggest that these trends in offtake, especially in the more heavily hunted mid-altitudes of the study area, indicate a decline in the population within this range. If this situation is widespread throughout the island, it is likely that unregulated bushmeat hunting will have devastating consequences to the biodiversity of Bioko Island, particularly for heavily hunted species that are naturally less abundant. [ABSTRACT FROM AUTHOR]

Red-legged partridge (Alectoris rufa) populations have significantly declined in the Iberian Peninsula (by > 50% between 1973 and 2002). This decline has been attributed to the drastic changes that have occurred in traditional agricultural landscapes, among other factors. This paper assesses the relationship between landscape change and the changes in areas favourable to partridges. The areas favourable to partridges in Andalusia (southern Spain), and the environmental and land-use factors that determined these areas, were identified for both the 1960s and the 1990s. Land-use changes were analysed both throughout the study area and for areas where favourability for partridges has either improved or worsened during recent decades. Both the location and the factors determining areas favourable to red-legged partridges have changed substantially over recent decades. In the 1960s, areas favourable to partridges were associated mainly with natural vegetation in mountainous areas, whereas, by the 1990s, favourable areas were associated with large low-lying croplands; such change may be attributable to regional land-use changes. The percentage area of the main natural vegetation variables positively correlated to partridge favourability in the 1960s model (mainly pastures and open scrubland) had decreased in areas that had become unfavourable to the species (such as mountain areas), and risen where partridge favourability increased. By the 1990s, the land area favourable to partridges had decreased by c. 10% (c. 6000 km2) in southern Spain, whereas land use unfavourable to partridges markedly increased (> 100%; an increase of c. 3000 km2). Landscape suitable for partridges has thus become severely impoverished over recent decades in the Iberian Peninsula. Management measures aimed at improving the landscape for farmland birds should be encouraged to conserve red-legged partridge populations in southern Spain. [ABSTRACT FROM PUBLISHER]

During the spring and summer of 2010 evidence was found that otters were using artificial lakes on golf courses in southern Spain as feeding areas. The remains of carp and turtles eaten by the otters were found. The presence of these otters may be influences by distances to and connections with natural habitats of the species. The use of these lakes as a potential feeding area is occurring at a time when there is a great deal of environmental stress in the Mediterranean region. [ABSTRACT FROM AUTHOR]

Understanding the biogeography of species in space and time is essential for the development of evidence‐based conservation and management plans. In this paper we propose a biogeographical spatial modelling approach based on the favourability function, and developed under a fuzzy logic framework, to unravel the historical biogeography of the two European wild rabbit subspecies, Oryctolagus cuniculus algirus (Oca) and Oryctolagus cuniculus cuniculus (Occ), in the Iberian Peninsula (IP).We first reviewed published and unpublished information (PhD theses, scientific papers, technical reports, etc.) on the occurrence of each rabbit subspecies throughout the IP. We compiled data from 201 Iberian rabbit populations and from genetic information of 4348 rabbits that was used to identify subspecies. Only populations in which all rabbits surveyed belonged to one subspecies were considered in the modelling procedure.We modelled rabbit subspecies' distribution separately for populations in which nuclear and mitochondrial DNA sequences were available. We employed a trend surface analysis developed by logistic regressions, which applied the favourability function and fuzzy logic operations.Using our approach we indentify the expansion cores from which both rabbit subspecies would have expanded after isolation during the last glaciations. Furthermore, we reveal the possible existence of a competitive exclusion zone between both rabbit subspecies that may have prevented their further expansion. Finally, our study shows that the Oca subspecies is distributed in north‐western areas previously attributed to Occ.This assessment of the actual and historical distribution of each rabbit subspecies may allow more specific conservation interventions, as the two subspecies are not just genetically distinct but also ecologically and behaviourally different. Our methodological approach could be useful in unravelling the historical biogeography of other lesser‐known species. [ABSTRACT FROM AUTHOR]

Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting. [ABSTRACT FROM AUTHOR]

Abstract Measuring hunting sustainability across West/Central African forests remains a challenge. Long-term assessment of trends is crucial. Via hunter-reported surveys we collected offtake data in three villages near the Dja Biosphere Reserve (southeast Cameroon). During four months (March–June) in 2003, 2009 and 2016, we gathered information on hunters, prey species and number of carcasses brought to the three settlements. Because it was not possible to record hunter effort i.e. the time a hunter spent pursuing animals or setting traps, to calculate catch per unit effort (CPUE), we used catch per hunter per day (CPHD) to document hunter returns. We then used the changes in the mean body mass indicator (MBMI) throughout the study period to test for defaunation in the three villages. Differences in CPHD and MBMI by month and year, between villages and hunting method, were investigated using Tweedie regression models. For all species pooled, we found that the mean CPHD remained relatively constant between 2003 and 2016. There was an observed shift from traps to firearms during the study period. CPHD for each of the seven most hunted species did not vary significantly during the entire study period, and a similar change from traps to firearms was observed. MBMI also remained stable for all species pooled, but significantly declined in the remotest village. Starting MBMI values for this village were higher than for the other two settlements perhaps because wildlife here is less depleted. Although hunter effort data may be difficult to obtain over long time periods, CPHD and MBMI may be useful tools as a measure of impact of hunters on prey populations. Highlights • Long-term monitoring of hunting offtake in tropical forests is fundamental to achieve sustainability. • Catch per hunter per day and mean body mass indicator of hunted prey can be used to document extraction patterns over time. • Notwithstanding some caveats, these measures can still be used as a good indication of changes in prey offtake. [ABSTRACT FROM AUTHOR]

Ebola virus is responsible for the fatal Ebola virus disease ( EVD)., Identifying the distribution area of the Ebola virus is crucial for understanding the risk factors conditioning the emergence of new EVD cases. Existing distribution models have underrepresented the potential contribution that reservoir species and vulnerable species make in sustaining the presence of the virus., In this paper, we map favourable areas for Ebola virus in Africa according to environmental and zoogeographical descriptors, independent of human-to-human transmissions. We combine two different biogeographical approaches: analysis of mammalian distribution types (chorotypes), and distribution modelling of the Ebola virus., We first obtain a model defining the distribution of environmentally favourable areas for the presence of Ebola virus. Based on a review of mammal taxa affected by or suspected of exposure to the Ebola virus, we model favourable areas again, this time according to mammalian chorotypes. We then build a combined model in which both the environment and mammalian distributions explain the favourable areas for Ebola virus in the wild., We demonstrate that mammalian biogeography contributes to explaining the distribution of Ebola virus in Africa, although vegetation may also underscore clear limits to the presence of the virus. Our model suggests that the Ebola virus may be even more widespread than previously suspected, given that additional favourable areas are found throughout the coastal areas of West and Central Africa, stretching from Cameroon to Guinea, and extend further East into the East African Lakes region., Our findings show that the most favourable area for the Ebola virus is significantly associated with the presence of the virus in non-human mammals. Core areas are surrounded by regions of intermediate favourability, in which human infections of unknown source were found. The difference in association between humans and other mammals and the virus may offer further insights on how EVD can spread. [ABSTRACT FROM AUTHOR]