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1.
Sci Total Environ ; 927: 172356, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38614338

ABSTRACT

Roads represent one of the main sources of wildlife mortality, population decline, and isolation, especially for low-vagility animal groups. It is still not clearly understood how wildlife populations respond to these negative effects over space and time. Most studies on wildlife road mortality do not consider the spatial and temporal components simultaneously, or the imperfect roadkill detection, both of which could lead to inaccurate assumptions and unreliable mitigation actions. In this study, we applied a multi-season occupancy model to a 14-year amphibian mortality dataset collected along 120 km of roads, combined with freely available landscape and remote sensing metrics, to identify the spatiotemporal patterns of amphibian roadkill in a Mediterranean landscape in Southern Portugal. Our models showed an explicit general decrease in amphibian roadkill. The Iberian painted frog (Discoglossus galganoi) experienced roadkill declines over time of ∼70 %, while the spiny common toad (Bufo spinosus) and the fire salamander (Salamandra salamandra) had a loss of nearly 50 %, and the Southern marbled newt (Triturus pygmaeus) had 40 %. Despite the decreasing trend in roadkill, spatial patterns seem to be rather stable from year to year. Multi-season occupancy models, when combined with relevant landscape and remote sensing predictors, as well as long-term monitoring data, can describe dynamic changes in roadkill over space and time. These patterns are valuable tools for understanding roadkill patterns and drivers in Mediterranean landscapes, enabling the differentiation of road sections with varying roadkill over time. Ultimately, this information may contribute to the development of effective conservation measures.


Subject(s)
Population Dynamics , Animals , Portugal , Amphibians/physiology , Environmental Monitoring/methods , Spatio-Temporal Analysis , Conservation of Natural Resources , Transportation
2.
J Environ Manage ; 348: 119221, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37913600

ABSTRACT

Roads are the second largest anthropogenic cause of mortality for most vertebrates. Previous research has analyzed the factors influencing roadkill either by species or by group of species based on some species-specific characteristics. However, to gain a comprehensive understanding on the consistency of findings within and between taxa, it is necessary to conduct an analysis that encompasses both individual species and group of species. This study aims to assess the role of taxonomic level in determining the spatial, climatic and temporal drivers using roadkill data for 70 species. We used generalized linear models to examine the association between roadkill and land cover and climate across 26 individual species and groups of reptiles, birds and mammals. Temporal patterns were evaluated using circular statistics. Our study revealed variations in spatial, climatic and temporal factors among taxa. For reptiles, spatial patterns differed between the class/order and species level, while climatic and temporal patterns remained consistent among these taxonomic levels. Spatial and climatic patterns were not consistent between class, order and associated species for birds and mammals. Temporal patterns, on the other hand, were consistent between each order and its associated species. In general, we found that roadkill incidence was positively associated with silviculture and agriculture cover as well as proximity of rivers. Accumulated insolation and mean minimum temperature were positively associated with roadkill, while mean temperature exhibited a negative association. Our study emphasizes the importance of analyzing roadkill variables on a species-specific basis. In the case of endangered species with low roadkill rates, it is essential to consider their assessment alongside other species exhibiting similar behavior and ecological needs.


Subject(s)
Mammals , Vertebrates , Animals , Birds , Reptiles , Endangered Species , Ecosystem
3.
PeerJ ; 10: e14291, 2022.
Article in English | MEDLINE | ID: mdl-36518279

ABSTRACT

Roads have considerable ecological effects that threaten the survival of some species, including many terrestrial carnivores. The western polecat is a small-medium sized mustelid native to Asia and Europe, including Britain where its historical stronghold is in Wales. Polecats are frequently killed on roads and road casualties represent the most common source of data on the species in the UK. However, little is known about the factors that increase the risk of collision. We used Generalized Additive Models to explore seasonal patterns in collisions as well as using Principal Component Analysis and regression modelling to identify landscape characteristics associated with polecat road casualties in Wales. Polecat road casualties had a bimodal distribution, occurring most frequently in March and October. Casualties were more frequently associated with road density, traffic volume, presence of rabbits, habitat patchiness and the abundance of proximal improved grassland habitat. Casualties were negatively associated with elevation and the abundance of semi-natural grassland habitat. The results of this study provide a framework for understanding and mitigating the impacts of roads on polecats in their historic stronghold, hence has considerable value to polecat conservation as well as broader applicability to ecologically similar species.


Subject(s)
Lagomorpha , Mustelidae , Animals , Rabbits , Wales/epidemiology , Europe , Ecosystem
4.
Biol Futur ; 73(3): 335-341, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35951219

ABSTRACT

Emys orbicularis is one of the freshwater turtles occurring in Europe, Middle East and Western Asia, but also occur in Caucasus region as Georgia, Armenia, Azerbaijan and Southern Caspian Sea region (northern Iran provinces as Guilan, Mazandaran, Golestan). In this study, seventeen localities in three Iranian provinces were investigated to study the response of this species to abiotic factors (water quality parameters) and road mortality. To test for differences in occurrence of E. orbicularis between sites that could be explained by variation in abiotic factors, one-way ANOVA test and Tukey's HSD post hoc tests were conducted. These showed significant differences in conductivity (CON) and Total Dissolved Solids (TDS) between locations in the three provinces of Golestan, Mazandaran and Gilan [CON: (F (2, 13) = 9.824, p = 0.003); TDS: (F (2, 13) = 13.957, p = 0.001)]. Differences in four other abiotic variables-water temperature, pH, salinity and dissolved oxygen (DO)-were not significant between provinces, although there were differences. These findings suggested that the species can occur in ponds with the following features: temperature 21-28 °C; pH 7-8; salinity > 750 mg/L; DO > 30%. Road mortality might be another factor that could contribute to the decline of this turtle's population in northern Iran, noting that the roads were created by human within the species' habitat and increased the mortality rate. Roads should be monitored in order to evaluate their effect on freshwater turtle mortality. Overall, our results demonstrated the advantage of using analysis of abiotic variables as a valid approach for defining species-responses to abiotic factors in E. orbicularis and recommended monitoring roads to find high-risk mortality of this species and create under road tunnels for moving turtles without any risk to reduce high rate of mortality.


Subject(s)
Turtles , Animals , Humans , Fresh Water , Iran/epidemiology , Oxygen
5.
Animals (Basel) ; 12(5)2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35268178

ABSTRACT

Dead specimens provide valuable data for the conservation of threatened species, allowing investigations of mortality, health conditions, and demographic parameters. The Eurasian otter (Lutra lutra) is a semiaquatic carnivore listed as endangered in Italy. In 2009, we started the first post mortem (PM) study of otters in Italy, through collaborative research between mammal ecologists and veterinary pathologists, using standardized protocols. Twenty-eight otters, mostly collected between 2009 and 2017, were examined. Most otters were males (67%), between 1 and 3 years old (64%), and predominantly in good nutritional condition. Adult males were significantly larger than adult females (p < 0.02), as expected for the species, although both sexes appeared to be smaller than otters examined in Central−northern Europe. The youngest sexually mature female was 3 years old. Road traffic collisions were the major cause of death, especially in young individuals, and mainly occurred in autumn−winter, particularly for females. Investigations of the scene of death contributed to revealing factors forcing otters to travel out of the water and move over the road, suggesting appropriate measures to reduce vehicle collision risk. Other causes of death included blunt chest trauma of uncertain origin, dog and conspecific attacks, or diseases of infectious or non-infectious origin, such as ulcerative gastritis, pleuropneumonia and peritonitis. Other diagnosed diseases included lymphoma. Ecto- and endoparasites were rarely detected, although we report the first documentation of heartworm and Ixodes hexagonus infestation in Italian otters. It is important to continue comprehensive, standardized PM investigations of otters in Italy to define baseline health, biometric and demographic parameters, collect biological samples for comparative analyses, and to reduce road-kill mortality. The present study suggests that the timely collection of carcasses and collaborative and coordinated research efforts are essential for obtaining useful data for the conservation of otters.

6.
Environ Manage ; 69(2): 429-437, 2022 02.
Article in English | MEDLINE | ID: mdl-34845534

ABSTRACT

We studied the impact of the new fenced and accident-safe motorway on the mortality of European badgers Meles meles on local roads in western Poland in 2010-2015. We monitored the badgers mortality on local roads of three categories: main roads, secondary roads and county roads. The study was conducted before and after the opening of the motorway in 2012. We hypothesized that the mortality of badgers is lower due to traffic concentration on motorway. Ninety two badgers were killed in collisions with vehicles on all monitored roads. Mean number of killed badgers was lowest in 2010 before the motorway opening and the highest in 2012. The mortality of badgers on regional roads was highest after the opening of the motorway due to the changes in traffic on the access roads. Within the road network, the mortality of badgers was 5.8 individuals/10 km of road per whole study period with the highest rate on main roads 8.5 individuals/10 km. The badgers mortality was highest on county roads but it was lower than expected in relation to the road network density. The highest vehicle collision risk for badgers of both sexes occurred in June. Distance to human settlements was the only environmental factor that was positively related to badger mortality on roads. We conclude that the new motorway did not reduce the mortality rate of badgers on the adjacent roads because the status of local roads has changed and now they mainly function as access roads to the motorway.


Subject(s)
Mortality , Mustelidae , Animals , Anthropogenic Effects , Female , Male , Poland , Transportation
7.
Ecol Evol ; 11(19): 13305-13320, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34646471

ABSTRACT

Collisions with vehicles can be a major threat to wildlife populations, so wildlife mitigation structures, including exclusionary fencing and wildlife crossings, are often constructed. To assess mitigation structure effectiveness, it is useful to compare wildlife road mortalities (WRMs) before, during, and after mitigation structure construction; however, differences in survey methodologies may make comparisons of counts impractical. Location-based cluster analyses provide a means to assess how WRM spatial patterns have changed over time. We collected WRM data between 2015 and 2019 on State Highway 100 in Texas, USA. Five wildlife crossings and exclusionary fencing were installed in this area between September 2016 and May 2018 for the endangered ocelot (Leopardus pardalis) and other similarly sized mammals. Roads intersecting State Highway 100 were mitigated by gates, wildlife guards, and wing walls. However, these structures may have provided wildlife access to the highway. We combined local hot spot analysis and time series analysis to assess how WRM cluster intensity changed after mitigation structure construction at fine spatial and temporal scales and generalized linear regression to assess how gaps in fencing and land cover were related to WRM cluster intensity in the before, during, and after construction periods. Overall, WRMs/survey day decreased after mitigation structure construction and most hot spots occurred where there were more fence gaps, and, while cluster intensity increased in a few locations, these were not at fence gaps. Cluster intensity of WRMs increased when nearer to fence gaps in naturally vegetated areas, especially forested areas, and decreased nearer to fence gaps in areas with less natural vegetation. We recommend that if fence gaps are necessary in forested areas, less permeable mitigation structures, such as gates, should be used. Local hot spot analysis, coupled with time series and regression techniques, can effectively assess how WRM clustering changes over time.

8.
Environ Manage ; 67(2): 412-423, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33469694

ABSTRACT

The negative effects of roads on wildlife populations are a growing concern. Movement corridors and road-kill data are typically used to prioritize road segments for mitigation measures. Some research suggests that locations where animals move across roads following corridors coincide with locations where they are often killed by vehicles. Other research indicates that corridors and road-kill rarely occur in the same locations. We compared movement corridor and road mortality models as means of prioritizing road segments for mitigation for five species of felids in Brazil: tiger cats (Leopardus tigrinus and Leopardus guttulus were analyzed together), ocelot (Leopardus pardalis), jaguarundi (Herpailurus yagouaroundi), and puma (Puma concolor). We used occurrence data for each species and applied circuit theory to identify potential movement corridors crossed by roads. We used road-kill records for each species and applied maximum entropy to determine where mortality was most likely to occur on roads. Our findings suggest that movement corridors and high road mortality are not spatially associated. We suggest that differences in the behavioral state of the individuals in the species occurrence and road-kill data may explain these results. We recommend that the road segments for which the results from the two methods agree (~5300 km for all studied species combined at 95th percentile) should be high-priority candidates for mitigation together with road segments identified by at least one method in areas where felids occur in low population densities or are threatened by isolation effects.


Subject(s)
Felidae , Puma , Animals , Animals, Wild , Brazil , Cats , Population Density
9.
Animals (Basel) ; 10(9)2020 Aug 28.
Article in English | MEDLINE | ID: mdl-32872180

ABSTRACT

Transport infrastructure is a pervasive element in modern landscapes and continues to expand to meet the demands of a growing human population and its associated resource consumption. Road-induced mortality is often thought to be a major contributor to the marked declines of European hedgehog populations. This review synthesizes available evidence on the population-level impacts of road mortality and the threat to population viability for the five hedgehog species in Europe. Local and national studies suggest that road mortality can cause significant depletions in population sizes, predominantly removing adult males. Traffic collisions are a probable cause of fragmentation effects, subsequently undermining ecological processes such as dispersal, as well as the genetic variance and fitness of isolated populations. Further studies are necessary to improve population estimates and explicitly examine the consequences of sex- and age-specific mortality rates. Hedgehogs have been reported to use crossing structures, such as road tunnels, yet evaluations of mitigation measures for population survival probability are largely absent. This highlights the need for robust studies that consider population dynamics and genetics in response to mitigation. In light of ongoing declines of hedgehog populations, it is paramount that applied research is prioritised and integrated into a holistic spatial planning process.

10.
Conserv Biol ; 34(5): 1210-1220, 2020 10.
Article in English | MEDLINE | ID: mdl-32227646

ABSTRACT

Mortality of animals on roads is a critical threat to many wildlife populations and is poised to increase strongly because of ongoing and planned road construction. If these new roads cannot be avoided, effective mitigation measures will be necessary to stop biodiversity decline. Fencing along roads effectively reduces roadkill and is often used in combination with wildlife passages. Because fencing the entire road is not always possible due to financial constraints, high-frequency roadkill areas are often identified to inform the placement of fencing. We devised an adaptive fence-implementation plan to prioritize road sections for fencing. In this framework, areas along roads of high, moderate, and low levels of animal mortality (respectively, roadkill hotspots, warmspots, and coldspots) are identified at multiple scales (i.e., in circles of different diameters [200-2000 m] in which mortality frequency is measured). Fence deployment is based on the relationship between the amount of fencing being added to the road, starting with the strongest roadkill hotspots, and potential reduction in road mortality (displayed in mortality-reduction graphs). We applied our approach to empirical and simulated spatial patterns of wildlife-vehicle collisions. The scale used for analysis affected the number and spatial extent of roadkill hot-, warm-, and coldspots. At fine scales (e.g., 200 m), more hotspots were identified than at coarse scales (e.g., 2000 m), but combined the fine-scale hotspots covered less road and less fencing was needed to reduce road mortality. However, many short fences may be less effective in practice due to a fence-end effect (i.e., animals moving around the fence more easily), resulting in a trade-off between few long and many short fences, which we call the FLOMS (few-long-or-many-short) fences trade-off. Thresholds in the mortality-reduction graphs occurred for some roadkill patterns, but not for others. Thresholds may be useful to consider when determining road-mitigation targets. The existence of thresholds at multiple scales and the FLOMS trade-off have important implications for biodiversity conservation.


Un Plan Adaptativo para la Priorización de Secciones de Carretera para Cercar y Reducir la Mortalidad Animal Resumen La mortalidad de los animales en las carreteras es una amenaza muy importante para las poblaciones silvestres y se pronostica que aumentarán enérgicamente debido a la construcción continua y planeada de carreteras. Si estas nuevas carreteras no pueden evitarse, se necesitarán medidas efectivas de mitigación para detener la declinación de la biodiversidad. El cercado a lo largo de las carreteras reduce efectivamente los atropellamientos y se usa frecuentemente junto con los pasos de fauna. Ya que cercar por completo la carretera no siempre es posible debido a las restricciones financieras, es común identificar las áreas con una frecuencia alta de atropellamientos para que la colocación de cercas esté informada al respecto. Diseñamos un plan adaptativo de implementación de cercas para priorizar las secciones de carretera que requieren ser cercadas. En este marco de trabajo, identificamos las áreas a lo largo de las carreteras con un nivel alto, moderado y bajo de mortalidad animal (respectivamente, puntos calientes, cálidos y fríos de atropellamiento) a diferentes escalas (es decir, en círculos de diferentes diámetros [200-2000 m] dentro de los cuales se mide la frecuencia de la mortalidad). El despliegue de cercas está basado en la relación entre la cantidad de cercas que se van añadiendo a la carretera, iniciando en los puntos calientes de atropellamiento, y la reducción potencial de la mortalidad en la carretera (presentada en gráficas de reducción de la mortalidad). Aplicamos nuestra estrategia a los patrones espaciales empíricos y simulados de las colisiones entre vehículos y animales. La escala utilizada para el análisis afectó al número y a la extensión espacial de los puntos calientes, cálidos y fríos de los atropellamientos. A escalas finas (p. ej.: 200 m), se identificaron más puntos calientes que a escalas más amplias (p. ej.: 2000 m), pero combinadas las escalas finas, los puntos calientes cubrieron una superficie menor de la carretera y se necesitaron menos cercas para reducir la mortalidad. Sin embargo, muchas cercas cortas pueden ser menos efectivas en la práctica debido al efecto de fin de valla (es decir, que los animales se muevan alrededor de la cerca con mayor facilidad), lo que resulta en una compensación entre pocas cercas largas y muchas cercas cortas, que denominamos compensación de cercas FLOMS (pocas-largas-o-muchas-cortas). Los umbrales en las gráficas de reducción de la mortalidad se presentaron para algunos patrones de atropellamiento, pero no para otros. Los umbrales pueden ser útiles para considerar cuando se determinan los objetivos de mitigación para las carreteras. La existencia de los umbrales a escalas múltiples y la compensación de FLOMS tienen implicaciones importantes para la conservación de la biodiversidad.


Subject(s)
Animals, Wild , Conservation of Natural Resources , Animals , Biodiversity
11.
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
12.
Ecology ; 99(11): 2625, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30229895

ABSTRACT

Mortality from collision with vehicles is the most visible impact of road traffic on wildlife. Mortality due to roads (hereafter road-kill) can affect the dynamic of populations of many species and can, therefore, increase the risk of local decline or extinction. This is especially true in Brazil, where plans for road network upgrading and expansion overlaps biodiversity hotspot areas, which are of high importance for global conservation. Researchers, conservationists and road planners face the challenge to define a national strategy for road mitigation and wildlife conservation. The main goal of this dataset is a compilation of geo-referenced road-kill data from published and unpublished road surveys. This is the first Data Paper in the BRAZIL series (see ATLANTIC, NEOTROPICAL, and BRAZIL collections of Data Papers published in Ecology), which aims make public road-kill data for species in the Brazilian Regions. The dataset encompasses road-kill records from 45 personal communications and 26 studies published in peer-reviewed journals, theses and reports. The road-kill dataset comprises 21,512 records, 83% of which are identified to the species level (n = 450 species). The dataset includes records of 31 amphibian species, 90 reptile species, 229 bird species, and 99 mammal species. One species is classified as Endangered, eight as Vulnerable and twelve as Near Threatened. The species with the highest number of records are: Didelphis albiventris (n = 1,549), Volatinia jacarina (n = 1,238), Cerdocyon thous (n = 1,135), Helicops infrataeniatus (n = 802), and Rhinella icterica (n = 692). Most of the records came from southern Brazil. However, observations of the road-kill incidence for non-Least Concern species are more spread across the country. This dataset can be used to identify which taxa seems to be vulnerable to traffic, analyze temporal and spatial patterns of road-kill at local, regional and national scales and also used to understand the effects of road-kill on population persistence. It may also contribute to studies that aims to understand the influence of landscape and environmental influences on road-kills, improve our knowledge on road-related strategies on biodiversity conservation and be used as complementary information on large-scale and macroecological studies. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

13.
PeerJ ; 6: e5423, 2018.
Article in English | MEDLINE | ID: mdl-30123718

ABSTRACT

Conservation authorities invest heavily in the restoration and/or creation of wetlands to counteract the destruction of habitat caused by urbanization. Monitoring the colonization of these new wetlands is critical to an adaptive management process. We conducted a turtle mark-recapture survey in a 250 ha artificially created wetland complex in a large North American city (Toronto, Ontario). We found that two of Ontario's eight native turtle species (Snapping turtle (SN), Chelydra serpentina, and Midland Painted (MP) turtle, Chrysemys picta marginata) were abundant and both were confirmed nesting. The Blanding's turtle (Emydoidea blandingii) was present but not well established. Species richness and turtle density were not equally distributed throughout the wetland complex. We noted SN almost exclusively populated one water body, while other areas of the wetland had a varying representation of both species. The sex ratios of both SN and MP turtles were 1:1. We tracked the movement of Snapping and Blanding's turtles and found that most turtles explored at least two water bodies in the park, that females explored more water bodies than males, and that 95% of turtles showed fidelity to individual overwintering wetlands. We performed DNA analysis of two Blanding's turtles found in the created wetlands and could not assign these turtles to any known profiled populations. The genetic data suggest that the turtles probably belong to a remnant local population. We discuss the implications of our results for connectivity of artificial wetlands and the importance of the whole wetland complex to this turtle assemblage.

14.
PeerJ ; 6: e5413, 2018.
Article in English | MEDLINE | ID: mdl-30128196

ABSTRACT

Roads may have an important negative effect on animal dispersal rate and mortality and thus the functioning of local populations. However, road verges may be surrogate habitats for invertebrates. This creates a conservation dilemma around the impact of roads on invertebrates. Further, the effect of roads on invertebrates is much less understood than that on vertebrates. We studied the effect of roads on butterflies by surveying abundance, species richness and composition, and mortality in ten grassland patches along high-traffic roads (∼50-100 vehicles per hour) and ten reference grassland patches next to unpaved roads with very little traffic (<1 vehicle per day) in southern Poland. Five 200-m transects parallel to the road were established in every grassland patch: at a road verge, 25 m from the verge, in the patch interior, and 25 m from the boundary between the grassland and field and at the grassland-arable field boundary. Moreover, one 200-m transect located on a road was established to collect roadkilled butterflies. The butterfly species richness but not abundance was slightly higher in grassland patches adjacent to roads than in reference grassland patches. Butterfly species composition in grasslands adjacent to roads differed from that in the reference patches. Proximity of a road increased variability in butterfly abundances within grassland patches. Grassland patches bordering roads had higher butterfly abundance and variation in species composition in some parts of the grassland patch than in other parts. These effects were not found in reference grassland patches, where butterfly species and abundance were more homogenously distributed in a patch. Plant species composition did not explain butterfly species. However, variance partitioning revealed that the presence of a road explained the highest proportion of variation in butterfly species composition, followed by plant species richness and abundance in grassland patches. Road mortality was low, and the number of roadkilled butterflies was less than 5% of that of all live butterflies. Nevertheless, the number and species composition of roadkilled butterflies were well explained by the butterfly communities living in road verges but not by total butterfly community structure in grassland patches. This study is the first to show that butterfly assemblages are altered by roads. These results indicate that: (1) grassland patches located near roads are at least as good habitats for butterflies as reference grassland patches are, (2) roads create a gradient of local environmental conditions that increases variation in the abundance of certain species and perhaps increases total species richness in grassland patches located along roads, and (3) the impact of roads on butterflies is at least partially independent of the effect of plants on butterflies. Furthermore, (4) the direct impact of road mortality is probably spatially limited to butterflies living in close proximity to roads.

15.
PeerJ ; 6: e5385, 2018.
Article in English | MEDLINE | ID: mdl-30083473

ABSTRACT

Roadkill has gradually become a common factor that has contributed to the decline of amphibians, and traffic volume is an important parameter that can be used to determine the impacts of roads. However, few researchers have studied the effects of either daily or nightly traffic volume on amphibian roadkill in China. Hence, as an essential step for implementing mitigation measures, we conducted 77 road surveys along 10 km of road in the Wanglang National Nature Reserve (NNR) to determine the temporal and spatial distribution patterns of amphibian road mortality. In total, 298 dead individuals (Bufo andrewsi and Rana chensinensis) were observed on the road from April to October in 2017 and during June and August in 2015 and 2016. B. andrewsi had the highest number of records (85.2%) and was more vulnerable to road mortality than R. chensinensis. Amphibian fatalities mainly occurred during the breeding season in April, but there was an additional concentration of B. andrewsi roadkill in June and July. There was a significantly positive correlation between amphibian road mortality and mean night-time traffic volume. Roadkill hotspots were non-randomly distributed throughout the study area and were mainly concentrated in the road sections near the breeding pools. Therefore, to effectively mitigate the effects of road mortality in the Wanglang NNR, measures should be implemented both during hot moments and at hotspots. First, based on roadkill hot moments, during the breeding season (in April) and in June and July, the Wanglang NNR should establish temporary traffic restraints at night. Second, based on roadkill hotspots, culverts should be established in areas near breeding pools adjacent to roads, and barrier walls should be installed to guide amphibians into the culverts.

16.
Environ Monit Assess ; 190(7): 413, 2018 Jun 20.
Article in English | MEDLINE | ID: mdl-29926192

ABSTRACT

The growing rate of wildlife underpass use for the mitigation of road-induced wildlife mortality necessitates the development of low-cost monitoring tools for determination of mitigation success. Trail cameras are one such tool that can provide valuable insight into the usage patterns and effectiveness of wildlife underpasses. We deployed trail cameras in wildlife underpasses in Guelph, ON, to develop recommendations for camera monitoring protocols. The trail cameras used high interval time lapse and motion sensors from April to October of 2016 to capture crossing by a variety of species through two slotted, small animal underpasses. Daily and seasonal underpass usage patterns of 21 species and species groups suggest that to comprehensively monitor underpass usage, cameras must be active continuously and utilize high frequency time lapse and motion sensors simultaneously to capture crossing events by both endothermic and ectothermic species. Although these recommendations are dependent on the specific objectives and target conservation species, these results can be used to guide a range of underpass monitoring programs.


Subject(s)
Environmental Monitoring/methods , Photography , Remote Sensing Technology , Animals , Animals, Wild , Biodiversity
17.
Article in English | WPRIM (Western Pacific) | ID: wpr-960085

ABSTRACT

@#<p style="text-align: justify;"><strong>BACKGROUND AND OBJECTIVE:</strong> Road safety in the Philippines has been increasingly significant with the increasing level of industrialization and urbanization over the last decade. The main objective of the study was to determine the road safety performance for Metro Manila by computing for an index based on data and variables of road traffic over the past years.</p><p style="text-align: justify;"><strong>METHODOLOGY: </strong>The variables for index calculation included speed, alcohol, infrastructure, vehicle defect, and other unsafe driver behavior were drawn from the Metro Manila Development (MMDA) database complemented with literature review from several sources. Equal Weighting method was utilized, as this is the simplest, yet, least biased measurement suitable for the data at hand.</p><p style="text-align: justify;"><b>RESULTS AND CONCLUSION:</b> The Road Safety Performance Index for Metro Manila remains more or less constant over a five-year period, increasing and decreasing from 0.45 to 0.59 which means that Metropolitan Manila has fared poorly in all indicators. Metro Manila has a poor road safety performance as evidenced by the road safety index. There is a need to improve on all components of road safety identified in this study for the safety of road users. </p>


Subject(s)
Industrial Development , Urbanization , Philippines
18.
BMC Ecol ; 17(1): 24, 2017 06 26.
Article in English | MEDLINE | ID: mdl-28651557

ABSTRACT

BACKGROUND: Amphibians and reptiles are among the most endangered vertebrate species worldwide. However, little is known how they are affected by road-kills on tertiary roads and whether the surrounding landscape structure can explain road-kill patterns. The aim of our study was to examine the applicability of open-access remote sensing data for a large-scale citizen science approach to describe spatial patterns of road-killed amphibians and reptiles on tertiary roads. Using a citizen science app we monitored road-kills of amphibians and reptiles along 97.5 km of tertiary roads covering agricultural, municipal and interurban roads as well as cycling paths in eastern Austria over two seasons. Surrounding landscape was assessed using open access land cover classes for the region (Coordination of Information on the Environment, CORINE). Hotspot analysis was performed using kernel density estimation (KDE+). Relations between land cover classes and amphibian and reptile road-kills were analysed with conditional probabilities and general linear models (GLM). We also estimated the potential cost-efficiency of a large scale citizen science monitoring project. RESULTS: We recorded 180 amphibian and 72 reptile road-kills comprising eight species mainly occurring on agricultural roads. KDE+ analyses revealed a significant clustering of road-killed amphibians and reptiles, which is an important information for authorities aiming to mitigate road-kills. Overall, hotspots of amphibian and reptile road-kills were next to the land cover classes arable land, suburban areas and vineyards. Conditional probabilities and GLMs identified road-kills especially next to preferred habitats of green toad, common toad and grass snake, the most often found road-killed species. A citizen science approach appeared to be more cost-efficient than monitoring by professional researchers only when more than 400 km of road are monitored. CONCLUSIONS: Our findings showed that freely available remote sensing data in combination with a citizen science approach would be a cost-efficient method aiming to identify and monitor road-kill hotspots of amphibians and reptiles on a larger scale.


Subject(s)
Amphibians/physiology , Remote Sensing Technology/methods , Reptiles/physiology , Animals , Biodiversity , Ecosystem , Female , Male , Models, Biological , Seasons
19.
Conserv Biol ; 31(6): 1340-1349, 2017 12.
Article in English | MEDLINE | ID: mdl-28319283

ABSTRACT

Ex situ conservation tools, such as captive breeding for reintroduction, are considered a last resort to recover threatened or endangered species, but they may also help reduce anthropogenic threats where it is difficult or impossible to address them directly. Headstarting, or captive rearing of eggs or neonate animals for subsequent release into the wild, is controversial because it treats only a symptom of a larger conservation problem; however, it may provide a mechanism to address multiple threats, particularly near population centers. We conducted a population viability analysis of Australia's most widespread freshwater turtle, Chelodina longicollis, to determine the effect of adult roadkill (death by collision with motor vehicles), which is increasing, and reduced recruitment through nest predation from introduced European red foxes (Vulpes vulpes). We also modeled management scenarios to test the effectiveness of headstarting, fox management, and measures to reduce mortality on roads. Only scenarios with headstarting from source populations eliminated all risks of extinction and allowed population growth. Small increases in adult mortality (2%) had the greatest effect on population growth and extinction risk. Where threats simultaneously affected other life-history stages (e.g., recruitment), eliminating harvest pressures on adult females alone did not eliminate the risk of population extinction. In our models, one source population could supply enough hatchlings annually to supplement 25 other similar-sized populations such that extinction was avoided. Based on our results, we believe headstarting should be a primary tool for managing freshwater turtles for which threats affect multiple life-history stages. We advocate the creation of source populations for managing freshwater turtles that are greatly threatened at multiple life-history stages, such as depredation of eggs by invasive species and adult mortality via roadkill.


Subject(s)
Conservation of Natural Resources/methods , Extinction, Biological , Food Chain , Foxes/physiology , Turtles/physiology , Animals , Australia , Fresh Water , Introduced Species , Longevity , New South Wales , Population Density , Population Dynamics , Predatory Behavior , Risk , Victoria
20.
Rev. MVZ Córdoba ; 21(2)May-Aug. 2016.
Article in English | LILACS-Express | LILACS | ID: biblio-1535358

ABSTRACT

Objective. Here we aimed to identify the main points of animal death by roadkill in the view of helping mitigation plans and reducing the impact over the local fauna of a protected area. Materials and methods. We surveyed the roads around a protected area of Cerrado (São Paulo, Brazil) from May 2012 to August 2013. We recorded the local of roadkills, biometric and morphologic data of the animals, and collected samples of tissue for molecular species confirmation. Results. Thirty-one roadkilled animals were registered, including threatened species: Leopardus pardalis; Cuniculus paca and Chrysocyon brachyurus. Most roadkills were represented by mammals (54.8%) and reptiles (38.7%), and the mortality rate was 1.46 animals/km/year. Three roadkill hotspots were detected, suggesting that they were important points of animal crossing, probably because of the existence of natural remnant vegetation and intersection of roads by riparian vegetation. Conclusions. This work provided strong evidence of the most critical points where mitigation strategies should be immediately implemented and highlighted the importance of detecting roadkill hotspots and the species or taxonomic groups more affected, helping to elaborate effective actions that can improve fauna conservation.


Objetivo. Identificar los principales puntos donde mueren animales para proponer planes de mitigación. Materiales y métodos. Se recorrieron las vías alrededor de una área protegida de Cerrado (São Paulo, Brasil) entre Mayo de 2012 y Agosto de 2013. Se registró el lugar del atropellamiento, datos biométricos y morfológicos de los animales y se colectaron muestras de tejido para la confirmación molecular de la especie. Resultados. Se registraron 31 animales atropellados (muertos), incluyendo especies amenazadas: Leopardus pardalis; Cuniculus paca y Chrysocyon brachyurus. La mayoría de los atropellamientos fueron representados por mamíferos (54.8%) y reptiles (38.7%) y la tasa de mortalidad fue de 1.46 animales/km/año. Fueron detectados tres hotspots de atropellamiento, sugiriendo que son puntos importantes en la probabilidad de cruce de animales, debido a un remanente de vegetación natural y la intercepción de la carretera con bosques de galería. Conclusiones. Este trabajo proporciona fuerte evidencia de los puntos más críticos donde las estrategias de mitigación deben ser implementadas inmediatamente y resalta la importancia de detectar hotspots de atropellamiento, las especies y los grupos taxonómicos más afectados ayudando a elaborar acciones efectivas que pueden mejorar la conservación de la fauna.

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