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1.
Sci Total Environ ; 946: 174216, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914319

RESUMO

Human-wildlife conflicts (HWC) are increasing and are potentially harmful to both people and wildlife. Understanding the current and potential distribution of wildlife species involved in HWC, such as carnivores, is essential for implementing management and conservation measures for such species. In this study, we assessed both the current distribution and potential distribution (forecast) of the Egyptian mongoose (Herpestes ichneumon) in the central part of the Iberian Peninsula. We acquired data concerning mongoose occurrences through an online questionnaire sent to environmental rangers. We used the municipality level as the sampling unit because all municipalities within the study area were covered at least by one ranger. Using the information provided by rangers (i.e. occurrences in their municipalities), we constructed environmental favourability distribution models to assess current and potential mongoose distribution through current distribution models (CDM) and ecological models (EM), respectively. >300 rangers participated in the survey and mongooses were reported in a total of 181 of 921 municipalities studied. The CDM model showed a current distribution mainly concentrated on the western part of the study area, where intermediate-high favourability values predominated. The EM model revealed a wider potential distribution, including the south-east part of the study area, which was also characterised by intermediate-high favourability values. Our predictions were verified using independent data, including confirmation of mongoose reproduction by rangers, reports by other experts, and field sampling in some areas. Our innovative approach based on an online survey to rangers coupled with environmental favourability models is shown to be a useful methodology for assessing the current distribution of cryptic but expanding wildlife species, while also enabling estimations of future steps in their expansion. The approach proposed may help policy decision-makers seeking to ensure the conservation of expanding wildlife species, for example, by designing awareness campaigns in areas where the target species is expected to arrive.

2.
Animals (Basel) ; 14(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338045

RESUMO

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.

3.
Sci Rep ; 11(1): 3503, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568774

RESUMO

A significant number of Baka Pygmies in Cameroon have been sedentarised in roadside villages, in contrast to their nomadic hunter-gatherer existence of the past. Although this change in lifestyle has had important consequences on health, most Baka villages still supplement their diets from forest products, especially wild meat. We used a combination of participatory methods and monitoring of individual hunters to map hunting territories in 10 Baka villages in southeastern Cameroon. From these, we determined whether wild meat extraction levels per village were related to the size of hunting territories, measured habitat use by hunters and finally defined the overlap between hunting territories and extractive industries in the region. Mapped village hunting areas averaged 205.2 ± 108.7 km2 (range 76.8-352.0 km2); all villages used a total of 2052 km2. From 295 tracks of 51 hunters, we showed that hunters travelled an average of 16.5 ± 13.5 km (range 0.9-89.8 km) from each village. Home ranges, derived from kernel utilization distributions, were correlated with village offtake levels, but hunter offtake and distance travelled were not significantly related, suggesting that enough prey was available even close to the villages. Hunters in all village areas exhibited a clear bias towards certain habitats, as indicated by positive Ivlev's index of selectivity values. We also showed that all village hunting territories and hunter home ranges fall within mining and logging concessions. Our results are important for local understanding of forest land uses and to reconcile these with the other land uses in the region to better inform decisions concerning land use policy and planning.

4.
Pest Manag Sci ; 74(1): 111-119, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28722344

RESUMO

BACKGROUND: Numerous small and medium-sized mammal pests cause widespread and economically significant damage to crops all over the globe. However, most research on pest species has focused on accounts of the level of damage. There are fewer studies concentrating on the description of crop damage caused by pests at large geographical scales, or on analysis of the ecological and anthropogenic factors correlated with these observed patterns. We investigated the relationship between agricultural damage by the European rabbit (Oryctolagus cuniculus) and environmental and anthropogenic variables throughout Spain. RESULTS: Rabbit damage was mainly concentrated within the central-southern regions of Spain. We found that rabbit damage increased significantly between the early 2000s and 2013. Greater losses were typical of those areas where farming dominated and natural vegetation was scarce, where main railways and highways were present, and where environmental conditions were generally favourable for rabbit populations to proliferate. CONCLUSION: From our analysis, we suggest that roads and railway lines act as potential corridors along which rabbits can spread. The recent increase in Spain of such infrastructure may explain the rise in rabbit damage reported in this study. Our approach is valuable as a method for assessing drivers of wildlife pest damage at large spatial scales, and can be used to propose methods to reduce human - wildlife conflict. © 2017 Society of Chemical Industry.


Assuntos
Agricultura , Produtos Agrícolas , Cadeia Alimentar , Coelhos , Animais , Controle de Pragas , Espanha
5.
PLoS One ; 11(9): e0161703, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27589384

RESUMO

We use data on game harvest from 60 Pygmy and non-Pygmy settlements in the Congo Basin forests to examine whether hunting patterns and prey profiles differ between the two hunter groups. For each group, we calculate hunted animal numbers and biomass available per inhabitant, P, per year (harvest rates) and killed per hunter, H, per year (extraction rates). We assess the impact of hunting of both hunter groups from estimates of numbers and biomass of prey species killed per square kilometre, and by examining the proportion of hunted taxa of low, medium and high population growth rates as a measure of their vulnerability to overhunting. We then map harvested biomass (kg-1P-1Yr-1) of bushmeat by Pygmies and non-Pygmies throughout the Congo Basin. Hunting patterns differ between Pygmies and non-Pygmies; Pygmies take larger and different prey and non-Pygmies sell more for profit. We show that non-Pygmies have a potentially more severe impact on prey populations than Pygmies. This is because non-Pygmies hunt a wider range of species, and twice as many animals are taken per square kilometre. Moreover, in non-Pygmy settlements there was a larger proportion of game taken of low population growth rate. Our harvest map shows that the non-Pygmy population may be responsible for 27 times more animals harvested than the Pygmy population. Such differences indicate that the intense competition that may arise from the more widespread commercial hunting by non-Pygmies is a far more important constraint and source of conflict than are protected areas.


Assuntos
Conservação dos Recursos Naturais , Florestas , Animais , População Negra , Congo , Humanos
6.
PLoS One ; 9(11): e112367, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25372705

RESUMO

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.


Assuntos
Biodiversidade , Modelos Biológicos , África Central , Animais , Humanos , Dinâmica Populacional
7.
Acta Parasitol ; 59(2): 259-62, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24827095

RESUMO

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.


Assuntos
Ectoparasitoses/veterinária , Sanguessugas/crescimento & desenvolvimento , Tartarugas/parasitologia , Animais , Ectoparasitoses/parasitologia , Masculino , Espanha
8.
Conserv Biol ; 28(1): 224-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24024960

RESUMO

Bushmeat markets exist in many countries in West and Central Africa, and data on species sold can be used to detect patterns of wildlife trade in a region. We surveyed 89 markets within the Cross-Sanaga rivers region, West Africa. In each market, we counted the number of carcasses of each taxon sold. During a 6-month period (7594 market days), 44 mammal species were traded. Thirteen species were on the International Union for Conservation of Nature (IUCN) Red List or protected under national legislation, and at least 1 threatened species was traded in 88 of the 89 markets. We used these data to identify market groups that traded similar species assemblages. Using cluster analyses, we detected 8 market groups that were also geographically distinct. Market groups differed in the diversity of species, evenness of species, and dominant, prevalent, and characteristic species traded. We mapped the distribution of number of threatened species traded across the study region. Most threatened species were sold in markets nearest 2 national parks, Korup National Park in Cameroon and Cross River in Nigeria. To assess whether the threatened-species trade hotspots coincided with the known ranges of these species, we mapped the overlap of all threatened species traded. Markets selling more threatened species overlapped with those regions that had higher numbers of these. Our study can provide wildlife managers in the region with better tools to discern zones within which to focus policing efforts and reduce threats to species that are threatened by the bushmeat trade.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Mamíferos , Animais , Biodiversidade , Camarões , Mapeamento Geográfico , Nigéria
9.
Environ Manage ; 43(6): 1256-68, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19430827

RESUMO

Agricultural change has transformed large areas of traditional farming landscapes, leading to important changes in the species community assemblages in most European countries. We suspect that the drastic changes in land-use that have occurred in Andalusia (southern Spain) over recent decades, may have affected the distribution and abundance of game species in this region. This article compares the distribution of the main game species in Andalusia during the 1960s and 1990s, using data from maps available from the Mainland Spanish Fish, Game and National Parks Service and from recent datasets on hunting yield distributions, respectively. Big-game and small-game species were significantly segregated in southern Spain during the 1990s, as two clearly independent chorotypes (groups of species whose abundances are similarly distributed) were obtained from the classification analysis. In contrast, big-game and small-game species were not significantly segregated several decades ago, when there was only one chorotype consisting of small-game species and wild boar. The other three ungulates did not constitute a significant chorotype, as they showed positive correlations with some species in the group mentioned above. These changes seem to be a consequence of the transformations that have occurred in the Iberian Mediterranean landscape over the last few decades. The abandoning of traditional activities, and the consequent formation of dense scrubland and woodland, has led to an expansion of big-game species, and a decrease of small-game species in mountain areas. Moreover, agricultural intensification has apparently depleted small-game species populations in some agricultural areas. On the other hand, the increasingly intensive hunting management could be artificially boosting this segregation between small-game and big-game species. Our results suggest that the conservation and regeneration of traditional agricultural landscapes (like those predominating in the 1960s) should be a priority for the conservation of small-game species.


Assuntos
Biodiversidade , Geografia , Agricultura , Animais , Demografia , Pesqueiros , Geografia/classificação , Modelos Estatísticos , Dinâmica Populacional , Espanha , Tempo
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