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1.
J Environ Manage ; 361: 121263, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38820795

ABSTRACT

Roads are one of the most widespread structures that drive habitat loss and fragmentation. But they also restrict animal movement and drive landscape-level impacts on biodiversity. The South Pacific of Costa Rica is known for its high levels of biodiversity, but little has been done to reduce road impacts upon wildlife communities. To understand these impacts and advise on possible mitigation action, we used three key data approaches: 1. Camera traps, to survey wildlife activity along two major road sections that dissect the region's protected areas and biological corridors. Seventy-eight camera traps were deployed in secondary forest patches at different distances (between 200 m and 1 km) from the roads for six months and covariates were collected to explain the patterns found. 2. Citizen science data extracted from iNaturalist to identify roadkill "hotspots" along the roads. And 3. Circuitscape analysis, to assess how landscape structure could influence animal movement. Camera traps recorded 30 terrestrial species. Ocelots and agoutis displayed a negative effect of distance from protected area, while the Apex predators displayed a positive effect toward higher forest cover and vegetation density. Circuitscape analysis showed high connectivity throughout most of the area. Only a few locations showed higher flow (bottle neck locations), which coincided with roadkill "hotspots" identified through citizen science direct observations (70 observations of 21 species). Amalgamating data from the different analyses allow us to identify four key wildlife crossing locations (one of less priority) along the Inter-American Highway. We strongly recommend the placement of under/overpasses in these locations, with the aim to ensure wildlife safe movement and connectivity of wildlife populations in the region. Culvert modifications in the area could also be considered to incorporate wildlife underpasses at a reduced cost.


Subject(s)
Animals, Wild , Biodiversity , Conservation of Natural Resources , Ecosystem , Costa Rica , Conservation of Natural Resources/methods , Animals , Forests
2.
Braz. j. biol ; 84: e252093, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355861

ABSTRACT

Abstract The present study aimed to evaluate the diet of the free-living crab-eating fox by identifying the stomach contents of the 17 crab-eating foxes (Cerdocyon thous) roadkilled in two conservation units, both located in the Amazon rainforest. The food items were quantified by frequency of occurrence (FO) and percentage of occurrence (PO). The stomach contents were analysed for dry matter (DM), crude protein (CP), crude fibre (CF), ether extract (EE), and mineral matter (MM). Nitrogen-free extractives (NFE), metabolisable energy (ME) values, as well as the energy need for maintenance were estimated. The composition of the diet for the crab-eating fox presented 29 food items from the different taxonomic groups, with a greater diversity of items of animal origin (n=22), although the highest frequency of occurrence was gramineae (Poaceae) (41.18%). Among the items of animal origin, 21% were mammals, 18% reptiles, 10% amphibians, 9% invertebrates and 3% birds. A high content of CF (62.76%) were determined. Nitrogen-free extractive and dry matter averages were 5.91% and 141.82 kcal/100g, respectively. The average maintenance energy was 447.01 kcal/day. These findings suggesting that the crab-eating foxes have a generalist diet with an omnivorous diet in the Amazon basin, feeding on gramineae, fruits, insects, snakes, amphibians, birds and small mammals and have the same feeding habit that present in other Brazilian biomes.


Resumo Este estudo objetivou analisar a dieta do cachorro-do-mato, de vida livre, por meio da identificação do conteúdo estomacal de 17 Cerdocyon thous atropelados em duas unidades de conservação da Floresta Amazônica. O conteúdo estomacal foi analisado e os itens alimentares foram quantificados pela frequência de ocorrência (FO) e percentagem de ocorrência (PO). Também foram avaliados os teores de matéria seca (MS), proteína bruta (PB), fibra bruta (FB), extrato etéreo (EE) e, matéria mineral (MM). Foram estimados o extrativo não-nitrogenado (ENN), a energia metabolizável (EM) e a necessidade energética de manutenção. A composição da dieta do cachorro-do-mato apresentou 29 itens alimentares dos diferentes grupos taxonômicos, tendo uma maior diversidade de itens de origem animal (n=22), ainda que a maior FO tenha sido de gramíneas (Poaceae) (41.18%). Dentre os itens de origem animal, 21% eram mamíferos, 18% répteis, 10% anfíbios, 9% invertebrados e 3% aves. Determinou-se um alto teor de FB (62.76%). A média do ENN e da MS foi 5.91% e 141.82 kcal/100g, respectivamente. A média da energia de manutenção foi 447.01 kcal/dia. Estes achados sugerem que o cachorro-do-mato encontrado na Bacia Amazônica é um animal generalista com uma dieta onívora, se alimentando de gramíneas, frutos, insetos, serpentes, anfíbios, aves e pequenos mamíferos, portanto com o mesmo hábito alimentar relatado a esta espécie quando encontrada em outros biomas brasileiros.


Subject(s)
Animals , Rainforest , Foxes , Brazil , Diet/veterinary
3.
Braz. j. biol ; 842024.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469284

ABSTRACT

Abstract The present study aimed to evaluate the diet of the free-living crab-eating fox by identifying the stomach contents of the 17 crab-eating foxes (Cerdocyon thous) roadkilled in two conservation units, both located in the Amazon rainforest. The food items were quantified by frequency of occurrence (FO) and percentage of occurrence (PO). The stomach contents were analysed for dry matter (DM), crude protein (CP), crude fibre (CF), ether extract (EE), and mineral matter (MM). Nitrogen-free extractives (NFE), metabolisable energy (ME) values, as well as the energy need for maintenance were estimated. The composition of the diet for the crab-eating fox presented 29 food items from the different taxonomic groups, with a greater diversity of items of animal origin (n=22), although the highest frequency of occurrence was gramineae (Poaceae) (41.18%). Among the items of animal origin, 21% were mammals, 18% reptiles, 10% amphibians, 9% invertebrates and 3% birds. A high content of CF (62.76%) were determined. Nitrogen-free extractive and dry matter averages were 5.91% and 141.82 kcal/100g, respectively. The average maintenance energy was 447.01 kcal/day. These findings suggesting that the crab-eating foxes have a generalist diet with an omnivorous diet in the Amazon basin, feeding on gramineae, fruits, insects, snakes, amphibians, birds and small mammals and have the same feeding habit that present in other Brazilian biomes.


Resumo Este estudo objetivou analisar a dieta do cachorro-do-mato, de vida livre, por meio da identificação do conteúdo estomacal de 17 Cerdocyon thous atropelados em duas unidades de conservação da Floresta Amazônica. O conteúdo estomacal foi analisado e os itens alimentares foram quantificados pela frequência de ocorrência (FO) e percentagem de ocorrência (PO). Também foram avaliados os teores de matéria seca (MS), proteína bruta (PB), fibra bruta (FB), extrato etéreo (EE) e, matéria mineral (MM). Foram estimados o extrativo não-nitrogenado (ENN), a energia metabolizável (EM) e a necessidade energética de manutenção. A composição da dieta do cachorro-do-mato apresentou 29 itens alimentares dos diferentes grupos taxonômicos, tendo uma maior diversidade de itens de origem animal (n=22), ainda que a maior FO tenha sido de gramíneas (Poaceae) (41.18%). Dentre os itens de origem animal, 21% eram mamíferos, 18% répteis, 10% anfíbios, 9% invertebrados e 3% aves. Determinou-se um alto teor de FB (62.76%). A média do ENN e da MS foi 5.91% e 141.82 kcal/100g, respectivamente. A média da energia de manutenção foi 447.01 kcal/dia. Estes achados sugerem que o cachorro-do-mato encontrado na Bacia Amazônica é um animal generalista com uma dieta onívora, se alimentando de gramíneas, frutos, insetos, serpentes, anfíbios, aves e pequenos mamíferos, portanto com o mesmo hábito alimentar relatado a esta espécie quando encontrada em outros biomas brasileiros.

4.
Environ Monit Assess ; 196(1): 89, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38147172

ABSTRACT

One of the most obvious impacts of roads is roadkill, a problem that is recently being addressed in Mexico. However, there are economic and human resource limitations to monitor the entire road network, assess its impacts, and propose mitigation measures. The black bear (Ursus americanus) is a top predator and the largest terrestrial mammal distributed in Mexico, currently the only of the Ursidae family. In recent years, its presence near human settlements and incidents on roads has increased. We generated a single MaxEnt model to identify characteristics of sites with high black bear roadkill risk and to identify these areas within protected natural areas. We obtained 83 bear roadkill records between 2008 and 2022, and we used a set of 16 variables that included landscape, road variables, and human variables. The model had an area under curve value of 0.96 indicating good performance and the Jacknife analysis identified influence on the roadkill risk of the distance to water bodies, protected areas, scrubland, drainages, and speed limit. We identified 3883.25 km of roads at high roadkill risk for black bears of which, 373.10 (9.6%) km were inside protected areas. We suggest placing speed bumps and effective signage on high-risk sections as a short-term, low-cost strategy. The results help to focus conservation efforts to specific sections of the road network, as roadkill is an increasing source of mortality that has not been evaluated for black bear in Mexico. This information is applicable for mitigating the impacts of existing roads and for planning new projects that have less impact on wild black bear populations and, at the same time, increase the safety of vehicle drivers.


Subject(s)
Ursidae , Humans , Animals , Mexico , Environmental Monitoring , Area Under Curve
5.
Braz J Vet Med ; 45: e001023, 2023.
Article in English | MEDLINE | ID: mdl-37649963

ABSTRACT

In this study, we conducted a retrospective survey of 63 giant anteaters (Myrmecophaga tridactyla) using the Federal University of Uberlândia, Minas Gerais State, Brazil as reference site for wild animals. We analyzed the clinical records of 63 animals from January 2016 to February 2020. The information obtained included the location where the anteater was found, the reason for rescue, estimated life stage, gender, weight, general condition of the animal, clinical signs, diagnosis, and destination. Of the 63 animals, 30.15%, (n = 19/63) were found in rural areas, 25.40% (n = 16/63) in urban areas, and 22.22% (n = 14/63) near highways. The main reason for rescue was run-over accidents (n = 18/63, 28.60%). Regarding life stage distribution, 27% (n = 17/63) were cubs, 25.40% (n = 16/63) were adolescent, and 41.26% (n = 26/63) were adults. There was a higher frequency of females (n = 35/63, 56%), and three (9%) of them were pregnant or had cubs. For injury evaluation, three of the 63 giant anteaters were dead on arrival at the rehabilitation site; therefore, we excluded them from this aspect of the study. Of the 60 remaining anteaters, only 13.33% (n = 8/60) of the animals were healthy upon physical examination.The most common condition was traumatic brain injury (n = 32/60 53.33%), followed by fractures (n = 23/60, 38.33%), neonate triad (n = 15/60, 25%), and abrasions (n = 15/60, 25%). The animals presented a high mortality rate (n = 39/60, 65%). The low number of giant anteaters reintroduced to their natural habitat and the high mortality rate of animals sent to rehabilitation centers show that the protection of giant anteaters is important to reduce the number of these animals sent to rehabilitation centers.


Foi realizado um levantamento retrospectivo de 63 tamanduás-bandeira (Myrmecophaga tridactyla) atendidos em um centro de animais selvagens referência na Universidade Federal de Uberlândia, Minas Gerais, Brasil. Foram analisados registros clínicos de 63 animais de janeiro de 2016 a fevereiro de 2020. As informações coletadas foram: local onde foi encontrado, motivo do resgate, idade estimada, sexo, peso, estado geral do animal, sinais clínicos, diagnóstico e destinação. Os animais foram encontrados em áreas rurais (30.15%, n = 19/63), áreas urbanas (25.40%, n = 16/63) e próximo a rodovias (22.22%, n = 14/63). O principal motivo do resgate foram os atropelamentos (28.60%, n = 18/63). A faixa etária foi de 27% (n = 17/63) filhotes, 25.40% (n = 16/63) jovens e 41.26% (n = 26/63) adultos. Encontrou-se maior frequência de fêmeas (56%, n = 35/63), sendo que três (9%) estavam prenhes ou com os filhotes nas costas. Apenas 13.33% (n = 8/60) dos animais apresentavam-se saudáveis ao exame físico. A condição mais comum foi traumatismo cranioencefálico (53,33%, n = 32/60), seguida por fraturas (38.33%, n = 23/60), tríade neonatal (25%, n = 15/60) e escoriações (25%, n = 15/60). Os animais apresentaram alta taxa de mortalidade (65%, n = 39/60). O baixo número de tamanduás reintroduzidos em seu habitat natural e a alta taxa de mortalidade de animais encaminhados para centros de reabilitação, mostram a importância de medidas que os protejam a ponto de reduzir o número de animais encaminhados para esses centros.

6.
Iheringia, Sér. zool ; 113: e2023007, 2023. tab, graf, mapas
Article in English | VETINDEX | ID: biblio-1434002

ABSTRACT

Understanding the ecological impacts of roads on mammals requires periodic monitoring of roads, and identification of both temporal and spatial distribution of roadkills (i.e., roadkill hotspots). The main aim of the study was to identify the most roadkilled mammals and evaluate the temporal and spatial distribution of roadkills in the RJ-122, a highway that crosses the threaten lowland Atlantic Forest in the state of Rio de Janeiro, southeast Brazil. Between October 2017 and January 2020, an intense monitoring study was conducted, with the carcasses of the roadkilled mammals being collected three times a week. Overall, we recorded 295 roadkilled mammals belonging to 22 species, resulting in 11 roadkills per month for the RJ-122 highway. The black-eared opossum, Didelphis aurita (N=149, 51%) stood out as the most roadkilled mammal, followed by porcupine, Coendou spinosus (N= 24, 8%), crab-eating fox, Cerdocyon thous (N= 23, 8), nine-banded armadillo, Dasypus novemcinctus (N= 23, 8%), and white-tufted marmoset, Callithrix jacchus (N= 20, 7%). Roadkills on the RJ-122 varied throughout the year, being more frequent in the rainy season (N=180) than in the dry season (N=115), and were concentrated in two hotspots, indicating some critical points with high roadkill frequency. Hotspots were associated with areas with dense natural vegetation, which can function as forest corridors in this fragmented landscape. Based on our results, several mitigation measures are recommended for the RJ-122 highway.(AU)


Compreender os impactos ecológicos das estradas sobre a fauna de mamíferos requer o monitoramento periódico das estradas e a identificação da distribuição temporal e espacial dos atropelamentos (ou seja, hotspots de atropelamentos). O objetivo principal do estudo foi identificar os mamíferos mais atropelados e avaliar a distribuição temporal e espacial dos atropelamentos na RJ-122, uma rodovia que atravessa a ameaçada Mata Atlântica de baixada no estado do Rio de Janeiro, sudeste do Brasil. Entre outubro de 2017 e janeiro de 2020, foi realizado um intenso estudo de monitoramento, com a coleta três vezes por semana das carcaças dos mamíferos atropelados. Ao todo, registramos 295 mamíferos atropelados pertencentes a 22 espécies, resultando em 11 atropelamentos por mês para a rodovia RJ-122. O gambá-de-orelha-preta, Didelphis aurita (N=149, 51%) destacou-se como o mamífero mais atropelado, seguido pelo ouriço-cacheiro, Coendou spinosus (N= 24, 8%), cachorro-do-mato, Cerdocyon thous (N= 23, 8%), tatu-galinha, Dasypus novemcinctus (N= 23, 8%) e sagui-de-tufo-branco, Callithrix jacchus (N= 20, 7%). Os atropelamentos na RJ-122 variaram ao longo do ano, sendo mais frequentes na estação chuvosa (N=180) do que na estação seca (N=115), e se concentraram em duas áreas, indicando alguns pontos críticos com alta frequência de atropelamentos. Os hotspots foram associados a áreas com vegetação natural densa, que podem funcionar como corredores florestais nesta paisagem fragmentada. Com base em nossos resultados, várias medidas de mitigação são recomendadas para a rodovia RJ-122.(AU)


Subject(s)
Animals , Accidents, Traffic , Mammals , Brazil , Spatio-Temporal Analysis
7.
Braz. j. biol ; 83: e263311, 2023. tab, graf, mapas
Article in English | VETINDEX | ID: biblio-1429983

ABSTRACT

Being a significant global biodiversity hotspot, the Atlantic Forest has been drastically reduced by human activities. Among the anthropic activities that most affect the biodiversity of this biome is the construction and operation of roads and highways. Between harmful effects of these infrastructures, wildlife roadkill is currently considered one of the biggest causes of mortality of wild vertebrates. This study evaluated patterns of vertebrates' roadkill on two roads in the coastal region of the largest continuous remnant of the Brazilian Atlantic Forest. For twelve months, we carry out weekly samples with a motor vehicle at a constant speed of 40 km/h to search for carcasses along the roads. All carcasses found were georeferenced and identified to the lowest possible taxonomic level. Then, using Siriema v.2.0 software, we analyzed roadkill aggregation and the spatial distribution of hotspots of wildlife roadkill. In 43 sampling days, 209 road-killed animals were registered (average roadkill rate of 0.105 and 0.111 animals/kilometer/day for PR-407 e PR-508, respectively). Extrapolating the rates found, we estimate that about 1,773 animals can be roadkill every year on these roads. The most affected groups were birds (33.01%) and amphibians (30.62%), followed by reptiles (19.13%) and mammals (17.33%). Warmer months had the highest roadkill rates. We found two critical roadkill hotspots for the PR-407 (kilometer 11.7 to 12.5 and kilometer 14.7 to 16.7). For the PR-508, we found a critical point of 5.2 km (kilometer 5 to 10.2). As a short-term measure, we recommend installing speed reducers in the identified stretches and implementing environmental education campaigns with residents and tourists, especially during the summer months, aiming to mitigate the roadkill on both roads. However, due to the importance and environmental fragility of the area, we emphasize the need for running periodic road ecology and local wildlife population viability studies in the medium and long term.


Sendo um importante hotspot de biodiversidade global, a Mata Atlântica tem sido drasticamente reduzida pelas atividades humanas. Entre as atividades antrópicas que mais afetam a biodiversidade desse ecossistema está a construção e operação de estradas e rodovias. Considerado um dos efeitos mais nocivos desses empreendimentos, o atropelamento de animais silvestres é atualmente uma das maiores causas de mortalidade de vertebrados silvestres. Neste estudo, avaliamos os padrões de atropelamentos de pequenos vertebrados em duas estradas na região litorânea do maior remanescente contínuo de Mata Atlântica brasileira. Durante doze meses realizamos coletas semanais com um veículo motorizado a uma velocidade constante de 40 km/h para busca de carcaças ao longo das estradas. Todas as carcaças encontradas foram georreferenciadas e identificadas até o menor nível taxonômico possível. Em seguida, usando o software Siriema v.2.0, analisamos a distribuição e os padrões espaciais dos eventos para identificar pontos de atropelamento de animais selvagens. Em um total de 43 dias de amostragem, foram registrados 209 animais atropelados (taxa média de atropelamentos de 0,105 e 0,111 animais/quilômetro/dia para PR-407 e PR-508 respectivamente). Extrapolando os índices encontrados, podemos estimar que cerca de 1.773 animais podem ser atropelados todos os anos nessas estradas. Os grupos mais afetados foram aves (33,01%) e anfíbios (30,62%), seguidos de répteis (19,13%) e mamíferos (17,33%). Os meses mais quentes tiveram as maiores taxas de atropelamentos. Durante o período encontramos dois pontos críticos de atropelamentos para a rodovia PR-407 (quilômetro 11,7 a 12,5 e quilômetro 14,7 a 16,7). Para a rodovia PR-508, encontramos um ponto crítico de 5,2 km (quilômetro 5 a 10,2). Como medida de curto prazo, recomendamos a instalação de redutores de velocidade nos trechos identificados e a implementação de campanhas de educação ambiental com moradores e turistas, principalmente nos meses de verão, visando mitigar o atropelamento em ambas as vias. No entanto, devido à importância e fragilidade ambiental da área, ressaltamos a necessidade de estudos de ecologia viária e de viabilidade populacional da fauna local a médio e longo prazo.


Subject(s)
Animals , Vertebrates , Roads , Accidents, Traffic , Animals, Wild
8.
Biota Neotrop. (Online, Ed. ingl.) ; 23(2): e20221454, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1447506

ABSTRACT

Abstract The construction of highways is responsible for access to previously protected areas, resulting in changes in landscape and dynamics of the animal populations that live in these areas. These enterprises are the major responsible for the mortality of wild animals, surpassing hunting and even the trafficking of animals. The objective of this study was to make a list that reflects the diversity of amphibians and reptile's road-killed along the BR-040, a highway that crosses the threaten lowland Atlantic Forest in Southeastern region of Brazil, including the use of microhabitats, lifestyle, activity pattern, reproductive cycles, and possible rare or endangered species. The study area consists of 180,4 km of highways. Monitoring began in 2006 and continues to the present day. A total of 1,410 individuals from 60 species were recorded in this study. The reptiles were more frequent in number of individuals and species. The commonest species recorded were Crotalus durissus and Dipsas mikanii. We have registered a single endangered species: Ranacephala hogei. The highest rates of road-kill were recorded during the wet season. Road-kills of fauna is a major threat to species, studies are of great importance to define plans that seek to mitigate the effects generated by these enterprises.


Resumo A construção de rodovias é responsável pelo acesso a áreas anteriormente protegidas, resultando em alterações na paisagem e na dinâmica das populações animais que vivem nessas áreas. Esses empreendimentos são os maiores responsáveis pela mortalidade de animais silvestres, superando a caça e até mesmo o tráfico de animais. O objetivo deste estudo foi realizar uma lista que reflita a diversidade de anfíbios e répteis atropelados ao longo da BR-040, uma rodovia que atravessa a ameaçada Mata Atlântica na região Sudeste do Brasil, incluindo o uso de microhabitats, estilo de vida, padrão de atividade, ciclos reprodutivos, e possíveis espécies raras ou ameaçadas. A área de estudo é constituída por 180,4 km de rodovias. O monitoramento começou em 2006 e segue até os dias atuais. Ao todo 1.410 indivíduos de 60 espécies foram registrados nesse estudo. Os répteis foram mais frequentes, em número de indivíduos e espécies. As espécies mais comumente registradas foram Crotalus durissus e Dipsas mikanii. Registramos uma espécie ameaçada de extinção: Ranacephala hogei. A maior taxa de atropelamento foi registrada durante a estação chuvosa. O atropelamento de fauna é uma grande ameaça as espécies, sendo de grande importância estudos para definição de planos que busquem mitigar os efeitos gerados por esses empreendimentos.

9.
J Comp Pathol ; 197: 1-18, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36089291

ABSTRACT

Motor vehicle collisions (MVCs) are a severe threat to wildlife biodiversity worldwide and most vertebrate species are at risk. However, there is a considerable knowledge gap on the traumatic features and potential patterns of MVCs in wildlife. We investigated traumatic injuries (TIs) caused by MVCs (MVCs-TIs) in 430 neotropical wild mammals representing 44 species from Brazil. Injuries were classified topographically into four categories: abdomen/pelvis (AP), chest (TX), head/neck (HN) and extremities (EX). We also determined the prevalence of pathological changes in MVC fatalities. AP (n = 381; 89%) was the most affected body segment, followed by TX (n = 372; 87%), HN (n = 363; 84%) and EX (n = 288; 67%). The most prevalent gross pathological findings were single or multiple bone fractures (n = 397; 92%), visceral organ rupture (n = 371; 86%), haemothorax (n = 220; 51%) and pulmonary haemorrhage (n = 212; 49%). Microscopically, pulmonary oedema (n = 324; 82%) and haemorrhage (n = 272; 69%) were the most prevalent lesions. No distinct TI patterns were evident across the various taxonomic groups, although trends were found in some taxa, such as armadillos. These results may help clinicians performing emergency care on MVC wildlife patients and may be of value in pathological and forensic investigations where a MVC has been deemed a likely contributory factor to death.


Subject(s)
Accidents, Traffic , Mammals , Animals , Brazil/epidemiology , Motor Vehicles , Prevalence
10.
J Environ Manage ; 321: 115903, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-35973292

ABSTRACT

For several species, roadkill is not spatially aggregated on hotspots, having instead a more diffuse pattern along the roads. For such species, management measures such as road passages may be insufficient for effective mitigation, since a large part of the road crossings is likely to occur outside the influence of those structures. One complementary approach could be to implement temporary mitigation actions, such as traffic calming. This requires understanding when roadkill peaks may occur. We tested the feasibility of predicting seasonal peaks of roadkill using data from a 3-year systematic monitoring (78 surveys over ca. 960 km of roads) from eight non-flying vertebrate species from Mato Grosso do Sul, Brazil, with different body size and life history traits (ca. 6400 records from focal species). We modelled the time-series of the roadkill of these species at large scale (state level) using generalized additive mixed models (GAMMs). We used the data of the first 2 years as training datasets, and the information from the third year of surveys as testing datasets to evaluate the prediction performance of models. Overall, the models of species feed with a higher number of records were able to follow reasonably well the variations of roadkill over time, although they were not able to correctly predict the number of collisions. For species with fewer observations, the models presented a poorer goodness-of-fit and prediction ability. Our results suggest that, at least for those species with higher roadkill rates, it can be possible to forecast periods of higher probability of occurring hot-moments of mortality. Such models can provide valuable information to implement seasonal management actions.


Subject(s)
Vertebrates , Animals , Brazil , Seasons
11.
Infect Genet Evol ; 99: 105246, 2022 04.
Article in English | MEDLINE | ID: mdl-35158084

ABSTRACT

Landscape transformation favors the spread of new pathogens that can be shared between domestic and wild animals. Certain adenoviruses (e.g., canine adenovirus 1 and 2, family Adenoviridae) can infect domestic and wild carnivores. In domestic canids, these viruses are associated with hepatic and respiratory diseases (among others). Nevertheless, information regarding adenovirus pathogenicity and molecular features in wild carnivores is still limited. Herein we surveyed adenovirus in free-ranging carnivores from Brazil. Total DNA was extracted from and subsequently tested by a nested panPCR in spleen and/or lung of 52 carnivores, representing species of the following families: Canidae (n = 4), Felidae (n = 3), Mustelidae (n = 2) and Procyonidae (n = 2). The obtained sequences were compared to others available at GenBank. Available tissue samples from the positive cases were evaluated histopathologically. One out of 52 (1.9%, CI 95%, 0.0-5.7%) carnivores was positive; a roadkilled ocelot (Leopardus pardalis). The obtained sequence presented a low deduced amino acid (78.1%) similarity with the closest adenovirus, identified in a pinniped from the United States of America. This fact and its detection in a novel host suggest it may be representative of a novel species and denominated ocelot adenovirus 1. None of the gross and microscopic findings of the positive case were associated with adenovirus. To the authors' knowledge, this is the first report of adenovirus in wild felids of South America and the second worldwide. Further studies are necessary to assess the epidemiology and potential pathogenicity of this agent in wild carnivores.


Subject(s)
Carnivora , Felidae , Adenoviridae/genetics , Animals , Animals, Wild , Brazil/epidemiology , Humans
12.
Parasitol Res ; 121(1): 225-233, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34807288

ABSTRACT

Maintenance of the life cycle of a wide diversity of helminths depends on the aquatic environment. Freshwater turtles are considered one of the main groups in these ecosystems due to their high density and biomass. However, there is little information on the infection parameters of helminths associated with the Chelidae species Hydromedusa tectifera, Phrynops hilarii, and Acanthochelys spixii that occur in the Pampa biome. Therefore, this study aimed at analyzing the gastrointestinal helminth assemblage of the three species. Analyses showed that A. spixii was associated with 11 helminth taxa while P. hilarii and H. tectifera were parasitized by eight taxa each. The gastrointestinal helminth assemblage of A. spixii and H. tectifera showed high similarity by the Morisita index. Infections suggest that the helminth fauna is directly related to the diet of the hosts, since A. spixii, P. hilarii, and H. tectifera are generalist and/or opportunistic with diets composed of various invertebrates, which, in turn, are part of the life cycles as intermediate hosts of most of the identified helminths. Thus, this study highlights not only the importance of helminthological research for the understanding of the biology of host organisms, but also the need for conservation of flooded areas characteristic of the Pampa biome, which is essential to maintain the diversity of the ecosystem.


Subject(s)
Helminthiasis, Animal , Helminths , Turtles , Animals , Brazil , Ecosystem , Fresh Water
13.
Heliyon ; 7(1): e06015, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33553734

ABSTRACT

Roadkill estimates for different species and species groups are available for many countries and regions. However, there is a lack of information from tropical countries, including from Latin America. In this study, we analyzed medium and large-sized mammal roadkill data from 18 toll road companies (TRC) in São Paulo State (6,580 km of monitored toll roads), Brazil. We extrapolated these roadkill numbers to the entire system of major paved roads in the State (36,503 km). The TRC collected mammal-road- mortality data both before (2-lanes) and after (4-lanes) road reconstruction. We used the "before" data from the TRC to estimate annual mammal-road-mortality along 2-lane roads that remained public roads. Combined with the data for the new 4-lane highways, this allowed us to estimate annual mammal road mortality for all the paved roads in the State. During 10 years of roadkill monitoring along toll roads, a total of 37,744 roadkilled mammals were recorded, representing a total of 32 medium to large-sized mammal species (average number of roadkilled individuals/year = 3,774 ± 1,159; min = 1,932; max = 5,369; 0.6 individuals roadkilled/km/year). Most roadkilled species were common generalists, but there were also relatively high roadkill numbers of threatened and endangered species (4.3% of the data), which is a serious conservation concern. Most of the roadkill was reported occurred during the nocturnal period (66%, n = 14,189) and in the rainy months (October-March) (55%, n = 15,318). Reported mammal roadkill tended to increase between 2009 and 2014 (R2 = 0.614; p = 0.065), with an average increase of 313.5 individuals/year. Extrapolation of the results to the entire São Paulo State, resulted in an average estimate of 39,605 medium and large-sized mammals roadkilled per year. Our estimates of the number of roadkilled individuals can be used as one of the input parameters in population viability analyses to understand the extinction or extirpation risk, especially for threatened and endangered species.

14.
J Comp Pathol ; 170: 34-45, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31375157

ABSTRACT

The lowland tapir (Tapirus terrestris) is the largest land mammal in South America. The species faces steady population decline due to poaching, habitat loss and fragmentation, road-kill, pesticide pollution, competition with domestic livestock and fires, among other threats. The lowland tapir is currently listed as vulnerable to extinction. Little information is available about natural disease processes for the species. This study aimed to report the pathological findings recorded in a cohort of 35 lowland tapirs killed by motor vehicle collision (MVC) on highways of Mato Grosso do Sul State, Brazil, between 2015 and 2018. The main gross pathological findings were those associated with MVC, primarily involving skeletal fractures and internal multiorgan damage with extensive bleeding and/or severe central nervous system injury. The most prevalent concurrent histopathological findings, unrelated to the cause of death, were: adrenal gland degeneration, necrosis and loss of fascicular and reticular cells with replacement fibrosis and cortical atrophy (9/15; 60%); interstitial pneumonia (20/34; 59%); glossitis (9/24; 38%); pulmonary anthracosis (12/34; 35%); colitis (9/28; 32%); and cholangitis/pericholangitis (9/35; 26%). The aetiopathogeneses and clinicopathological significance of some of these findings are unclear; however, parasitic infections appear to be common. Our results highlight the importance of wildlife health information obtained through the study of carcasses of roadkills.


Subject(s)
Animals, Wild , Perissodactyla , Accidents, Traffic , Animals , Brazil
15.
J Environ Manage ; 248: 109320, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31376609

ABSTRACT

We modelled the spatiotemporal patterns of road mortality for seven medium-large mammals, using a roadkill dataset from Mato Grosso do Sul, Brazil (800 km of roads surveyed every two weeks, for two years). We related roadkill presence-absence along the road sections (1000 m) and across the survey dates with a collection of environmental variables, including land cover, forest cover, distance to rivers, temperature, precipitation and vegetation productivity. We further included two variables aiming to reflect the intrinsic spatial and temporal roadkill risk. Environmental variables were obtained through remote sensing and weather stations, allowing the estimate of the roadkill risk for the entire surveyed roads and survey periods. Overall, the models could explain a small fraction of the spatiotemporal patterns of roadkills (<0.23), probably due to species being habitat generalists, but still had reasonable discrimination power (AUC averaging 0.70 ±â€¯0.07). The intrinsic spatial and temporal roadkill risk were the most important variables, followed by land cover, climate and NDVI. We show that identifying spatiotemporal roadkill patterns may provide valuable information to define specific management actions focused on road sections and time periods, in complement to permanent road mitigation measures. Our approach thus offers a new insight into the understanding of road effects and how to plan and strategize monitoring and mitigation.


Subject(s)
Ecosystem , Mammals , Animals , Brazil , Forests , Rivers
16.
Rev. biol. trop ; Rev. biol. trop;67(1): 47-60, Jan.-Mar. 2019. tab, graf
Article in English | LILACS | ID: biblio-1041893

ABSTRACT

Abstract Domestic animals are involved in a large number of traffic accidents and they represent danger to humans due to their size. Despite this, few studies consider domestic animals. That is why we evaluate mammals' roadkill aggregations in order to locate them and to determine if wild and domestic mammals' roadkills overlap. In addition, we investigate the influence of the landscape on the location of the aggregations. This study was carried out on the BR-050 highway, an area of Cerrado biome, in Southeastern Brazil. The monitoring was executed from April 2012 to March 2013, by car, at an average speed of 60 km/h, with two observers looking for roadkills on the highway. We found 482 mammals' roadkills, including 260 (54 %) wild mammals, 164 (34 %) domestic and 58 (12.0 %) undetermined specimens. Of the 21 recorded mammal species, five were domestic. The wild mammals' roadkill rate was 0.03 (± 0.02) individuals/km/day and the domestic roadkill rate was 0.02 (± 0.01). We detected roadkill aggregations for wild and domestic mammals. Roadkill hotspots of domestic mammals and wild mammals did not overlap. The variables that had the highest influence on wild mammals' roadkill probability were: agriculture and silviculture cover as positive effects and distance to the nearest river, to the urban perimeter and to a natural fragment as negative effects. For domestic mammals these variables were: area of the smallest fragment and distance to a natural fragment as positive effects and silviculture cover as a negative effect. The explanation for the wild and domestic mammals' roadkill hotspot non overlapping seems to be the effect of each variable in determining the roadkill hotspot since their effect is different for wild and domestic mammals. On the other hand, this non overlapping can be a result of domestic mammals' scavenging habits. We propose different kinds of mitigation measures in order to reduce domestic and wild mammals' roadkill.(AU)


Resumen Los animales domésticos están involucrados en una gran cantidad de accidentes de tránsito y representan un peligro para los humanos debido a su tamaño. A pesar de esto, pocos estudios consideran a los animales domésticos. Es por eso que evaluamos agregaciones de atropellos de mamíferos, con el fin de ubicarlas y determinar si los atropellos de los mamíferos silvestres y domésticos se traslapan. Además, investigamos la influencia del paisaje en la ubicación de las agregaciones. Este estudio se realizó en la carretera BR-050, un área del bioma Cerrado, en el sureste de Brasil. El muestreo se ejecutó entre abril 2012 y marzo 2013, en automóvil, a una velocidad promedio de 60 km/h, y dos observadores buscaron animales atropellados en la carretera. Encontramos 482 mamíferos atropellados, incluidos 260 (54 %) mamíferos silvestres, 164 (34 %) ejemplares domésticos y 58 (12 %) especímenes indeterminados. De las 21 especies de mamíferos registradas, cinco fueron de origen doméstico. La tasa de mortalidad de mamíferos silvestres fue de 0.033 (± 0.018) individuos/km/día y la de domésticos de 0.020 (± 0.008). Detectamos agregaciones de atropellos para mamíferos silvestres y domésticos. Los "hotspots" de atropellos de mamíferos domésticos y silvestres no se traslapan. Las variables que tuvieron la mayor influencia positiva en la probabilidad de atropello de mamíferos silvestres fueron: cobertura de la agricultura y la silvicultura; mientras que distancia al río más cercano, al perímetro urbano y al fragmento natural tuvieron un efecto negativo. Para los mamíferos domésticos estas variables con un efecto positivo fueron: área del fragmento más pequeño y distancia al fragmento natural; en tanto que la cobertura de silvicultura tuvo un efecto negativo. El que no haya un traslape de los atropellos de mamíferos silvestres y domésticos se podría explicar por el efecto de cada variable en la determinación de los "hotspots" de atropellos, ya que su efecto es diferente para los mamíferos silvestres y domésticos. Por otro lado, el no traslape puede ser el resultado de los hábitos carroñeros de los mamíferos domésticos. Proponemos diferentes tipos de medidas de mitigación con el fin de reducir los atropellos de los mamíferos domésticos y salvajes.(AU)


Subject(s)
Roads , Accidents, Traffic/trends , Animals, Domestic , Animals, Wild , Brazil , Sampling Studies , Spatial Analysis
17.
Sci Total Environ ; 660: 493-500, 2019 Apr 10.
Article in English | MEDLINE | ID: mdl-30640116

ABSTRACT

Transportation infrastructures are directly responsible for killing billions of animals worldwide. Although the understanding about road impacts have recently increased, the impact of railroads on wildlife has received less attention. The current knowledge concerning the impacts of railroads focuses mainly on large mammals although amphibians might be affected. Our study aims to unravel temporal and spatial patterns of Rhinella toad fatalities on a Brazilian Amazonian railroad, to comprehend how toads are killed and to estimate the magnitude of toad fatalities. Data collection was carried out on foot on an 871-km stretch of the Estrada de Ferro Carajás from 2013 to 2017. We identified different potential causes for fatalities: being run over, desiccated or with barotrauma signs. We estimated a surprisingly high carcass persistence probability of about 38 days. After correcting for the bias from carcass detection and removal, we estimated that approximately 10,000 toads are killed per year (≈ 11 fatalities/km/year). A GLM model showed that toads were more likely to be killed in the dry to wet transition. We identified critical zones of fatalities and prioritized them according to their intensity. The highly critical segments encompass >10% of all fatalities although they cover only 1.5% of the railroad. Our study is the first one to address carcass detection and persistence on railroads and to unravel patterns of fatalities of an amphibian species in a tropical climate. A better understanding of the patterns of animal fatality on railroads is of fundamental importance to manage and mitigate this impact.


Subject(s)
Bufonidae , Conservation of Natural Resources , Railroads , Animals , Brazil , Longevity , Population Dynamics
18.
Sci Total Environ ; 642: 629-637, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-29909330

ABSTRACT

Wildlife-vehicle collisions (WVC) represent a major threat for wildlife and understanding how WVC spatial patterns relate to surrounding land cover can provide valuable information for deciding where to implement mitigation measures. However, these relations may be heavily biased as many casualties are undetected in roadkill surveys, e.g. due to scavenger activity, which may ultimately jeopardize conservation actions. We suggest using occupancy models to overcome imperfect detection issues, assuming that 'occupancy' represents the preference for crossing the road in a given site, i.e. is a proxy for the roadkill risk; and that the 'detectability' is the joint probability of an animal being hit in the crossing site and its carcass being detected afterwards. Our main objective was to assess the roadkill risk along roads while accounting for imperfect detection issues and relate it to land cover information. We conducted roadkill surveys over 114 km in nine different roads, biweekly, for five years (total of 484 surveys), and developed a Bayesian hierarchical occupancy model to assess the roadkill risk for the six most road-killed taxa for each road section and season (WET and DRY). Overall, we estimated a higher roadkill risk in road sections surrounded by agriculture, open habitats; and a higher detectability within the 4-lane road sections. Our modeling framework has a great potential to overcome the limitations related to imperfect detection when assessing the roadkill risk and may become an important tool to predict which road sections have a higher mortality risk.


Subject(s)
Environmental Monitoring , Models, Statistical , Motor Vehicles/statistics & numerical data , Accidents, Traffic/statistics & numerical data , Animals , Animals, Wild , Bayes Theorem , Ecosystem , Probability
19.
Braz. J. Biol. ; 78(1): 125-132, Feb.2018. mapas, tab
Article in English | VETINDEX | ID: vti-732667

ABSTRACT

Roadkill impact is still underestimated due to the lack of knowledge of its intensity and effect on animal populations. To assess differences between animal roadkills on roads in distinct landscapes, this study recorded meso- and megavertebrate roadkills along 50 km during a year in two highways in the transitional area of Amazonia/Cerrado in Tangará da Serra, Mato Grosso: MT-358 and MT-235, the latter crossing the Paresi Indigenous Land. We assessed roadkill rates and points with higher rates of roadkills, recording the most impacted species, seasonal effects, biomass loss, activity period of species, and traffic volume. We recorded 178 roadkills in 4,950 km travelled, a rate of 0.035 animal/km-travelled. Mammals were the most impacted with 135 roadkills (75.8%), followed by reptiles (6.2%), amphibians (5.6%) and birds (5.1%). Among mammals 51.1% were Carnivora, and the most impacted species was Cerdocyon thous (n = 42). On highway MT-358 (human-modified landscape), we recorded 155 roadkilled mammals, and the most impacted were C. thous (23.9%) and Euphractus sexcinctus (13.5%). Whilst on highway MT-235 (Paresi Indigenous Land), we recorded 23 roadkilled mammals, and the most impacted were Myrmecophaga tridactyla (26.1%) and C. thous (21.7%). The low roadkill rate in the Paresi Indigenous Land might be related to the presence of fauna pathways along the highway and the availability of a forested landscape.(AU)


O impacto de atropelamentos por veículos sobre populações animais ainda é subestimado devido ao pouco conhecimento existente sobre sua intensidade e seus efeitos. Para avaliar diferenças entre atropelamentos de animais em rodovias inseridas em paisagens distintas, este trabalho registrou atropelamentos de meso e mega vertebrados em trechos de 50 km durante um ano em duas rodovias na região de transição Amazônia/Cerrado em Tangará da Serra, Mato Grosso: MT-358 e MT-235, sendo que a segunda cruza a Terra Indígena Paresi. Avaliamos as taxas de atropelamento e os locais de maior intensidade, registrando as espécies mais impactadas. Avaliamos efeitos de sazonalidade, perda de biomassa, horário de atividade das espécies e horário de maior fluxo de veículos. Foram 178 animais atropelados em 4.950 km percorridos, com 33 espécies (15 ordens), totalizando 0,035 animais/km-percorrido. Os mamíferos foram os mais atingidos com 135 atropelamentos (75,8%), seguidos por répteis (6,2%), anfíbios (5,6%) e aves (5,1%). Entre os mamíferos atropelados 51,1% pertencem à ordem carnívora, e a espécie mais atropelada foi Cerdocyon thous (n = 42). Na rodovia MT-358 (antropizada) foram registrados 155 atropelamentos de mamíferos, sendo que C. thous (23,9%) e Euphractus sexcinctus (13,5%) foram os mais atropelados. Enquanto na rodovia MT-235 foram registrados 23 atropelamentos sendo Myrmecophaga tridactyla (26.1%) e C. thous (21,7%) as espécies mais afetadas. Observamos menor taxa de atropelamentos dentro da Terra Indígena Paresi, possivelmente devido a presença de passagens para fauna ao longo da rodovia e maior quantidade de áreas florestadas.(AU)


Subject(s)
Animals , Roads/adverse effects , Roads/statistics & numerical data , Biodiversity , Vertebrates , Accidents, Traffic/statistics & numerical data , Brazil
20.
Braz. j. biol ; Braz. j. biol;78(1): 125-132, Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-888837

ABSTRACT

Abstract Roadkill impact is still underestimated due to the lack of knowledge of its intensity and effect on animal populations. To assess differences between animal roadkills on roads in distinct landscapes, this study recorded meso- and megavertebrate roadkills along 50 km during a year in two highways in the transitional area of Amazonia/Cerrado in Tangará da Serra, Mato Grosso: MT-358 and MT-235, the latter crossing the Paresi Indigenous Land. We assessed roadkill rates and points with higher rates of roadkills, recording the most impacted species, seasonal effects, biomass loss, activity period of species, and traffic volume. We recorded 178 roadkills in 4,950 km travelled, a rate of 0.035 animal/km-travelled. Mammals were the most impacted with 135 roadkills (75.8%), followed by reptiles (6.2%), amphibians (5.6%) and birds (5.1%). Among mammals 51.1% were Carnivora, and the most impacted species was Cerdocyon thous (n = 42). On highway MT-358 (human-modified landscape), we recorded 155 roadkilled mammals, and the most impacted were C. thous (23.9%) and Euphractus sexcinctus (13.5%). Whilst on highway MT-235 (Paresi Indigenous Land), we recorded 23 roadkilled mammals, and the most impacted were Myrmecophaga tridactyla (26.1%) and C. thous (21.7%). The low roadkill rate in the Paresi Indigenous Land might be related to the presence of fauna pathways along the highway and the availability of a forested landscape.


Resumo O impacto de atropelamentos por veículos sobre populações animais ainda é subestimado devido ao pouco conhecimento existente sobre sua intensidade e seus efeitos. Para avaliar diferenças entre atropelamentos de animais em rodovias inseridas em paisagens distintas, este trabalho registrou atropelamentos de meso e mega vertebrados em trechos de 50 km durante um ano em duas rodovias na região de transição Amazônia/Cerrado em Tangará da Serra, Mato Grosso: MT-358 e MT-235, sendo que a segunda cruza a Terra Indígena Paresi. Avaliamos as taxas de atropelamento e os locais de maior intensidade, registrando as espécies mais impactadas. Avaliamos efeitos de sazonalidade, perda de biomassa, horário de atividade das espécies e horário de maior fluxo de veículos. Foram 178 animais atropelados em 4.950 km percorridos, com 33 espécies (15 ordens), totalizando 0,035 animais/km-percorrido. Os mamíferos foram os mais atingidos com 135 atropelamentos (75,8%), seguidos por répteis (6,2%), anfíbios (5,6%) e aves (5,1%). Entre os mamíferos atropelados 51,1% pertencem à ordem carnívora, e a espécie mais atropelada foi Cerdocyon thous (n = 42). Na rodovia MT-358 (antropizada) foram registrados 155 atropelamentos de mamíferos, sendo que C. thous (23,9%) e Euphractus sexcinctus (13,5%) foram os mais atropelados. Enquanto na rodovia MT-235 foram registrados 23 atropelamentos sendo Myrmecophaga tridactyla (26.1%) e C. thous (21,7%) as espécies mais afetadas. Observamos menor taxa de atropelamentos dentro da Terra Indígena Paresi, possivelmente devido a presença de passagens para fauna ao longo da rodovia e maior quantidade de áreas florestadas.


Subject(s)
Animals , Automobile Driving , Vertebrates , Biodiversity , Transportation , Brazil/epidemiology
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