Andreas Kindel

Roadkills of vertebrate species on two highways through the Atlantic Forest Biosphere Reserve, southern Brazil

We assessed the magnitude, composition, and spatial and temporal patterns of road mortality of native vertebrates on two highways in southern Brazil from 18 January 2003 to 26 January 2004. The highways cross remnants of the Atlantic Rainforest, a global biodiversity hotspot, and differ in vehicle traffic and surrounding landscape. We compared the road-kill magnitude and composition of birds, mammals, and reptiles between roads and seasons. We used a modified K statistic to depict the spatial patterns of roadkills of these groups and tested the association between vehicle traffic and road mortality through linear regression. We recorded 869 kills of 92 species. The two roads differed regarding the abundance and composition of roadkills. Reptile road mortality was higher in summer than winter, but all other groups did not show significant difference in the magnitude of mortality between seasons. The composition of killed assemblages differed significantly for some of the taxonomic groups among seasons. We found only one positive association between roadkills and vehicle traffic (reptiles on one of the roads), suggesting that vehicle flow does not explain the road-kill temporal variation on these roads. Total vertebrate, bird, and mammal roadkills showed significant spatial aggregations possibly due to variation in vehicle traffic, highway design, and local landscape condition and arrangement. With expected expansion of the road network, mitigation measures for multi-species assemblages should include habitat protection, soil use regulation, road crossing structures, speed reducers, and campaigns to raise people’s awareness about road impacts on wildlife.

Anuran road-kills neighboring a peri-urban reserve in the Atlantic Forest, Brazil

Mortality from road-kills may figure among the important causes of decline in amphibian populations and species extinctions worldwide. Evaluation of the magnitude, composition, and temporal and spatial distributions of amphibian road-kills is a key step for mitigation planning, especially in peri-urban reserves. Once a month for 16 months, we surveyed, on foot, a 4.4 km section of state road ERS-389 bordering the Itapeva reserve in the southern Atlantic Forest. We recorded 1433 anuran road-kills and estimated a mortality rate of 9002 road-kills/km/year. The species most often recorded were the largest ones: Leptodactylus latrans, Rhinella icterica, Leptodactylus gracilis and Hypsiboas faber; 54.5% of the carcasses could not be identified. Anuran mortality was concentrated in summer, and was associated with temperature, rainfall and photoperiod. Leptodactylus road-kills were strongly influenced by vehicle traffic, probably because of its high abundance during the entire study period. Road-kill hotspots differed for anurans as a group and for single species, and we found an association among spatial patterns of mortality and types of land cover, distance from the nearest waterbody, roadside ditches, and artificial light. Traffic should be banned temporarily during periods of high mortality, which can be forecasted based on meteorological data. A comprehensive mitigation approach should take into account hotspots of all anuran records, and also of target species for selecting locations for amphibian passages and fencing. Roadside ditches, artificial waterbodies, and conventional street lights should be reduced as much as possible, since they may represent ecological traps for anuran populations.

Canopy bridges as road overpasses for wildlife in urban fragmented landscapes

Os efeitos do desmatamento e da fragmentacao de habitats sao exacerbados por elementos como rodovias e redes eletricas, que podem atuar como filtros ou barreiras aos movimentos da vida silvestre. Com o objetivo de mitigar a mortalidade e restaurar a conectividade, passagens de fauna tem sido construidas como corredores lineares. A instalacao dessas estruturas deve ser seguida de monitoramento sistematico, visando a avaliacao de seu uso e efetividade e a geracao de informacoes para seu manejo e para convencer os tomadores de decisao sobre seu valor. Neste artigo, apresentamos os resultados do monitoramento do uso de seis pontes de corda, realizado durante 15 meses, entre agosto de 2008 e outubro de 2009, nas imediacoes da Reserva Biologica do Lami Jose Lutzenberger, em Porto Alegre, Brasil. As pontes de dossel foram instaladas pelo Nucleo de Extensao Macacos Urbanos em locais com registros de atropelamentos e choques eletricos de bugios-ruivos (Alouatta guariba clamitans Cabrera, 1940). Instalamos armadilhas fotograficas em cada ponte e selecionamos moradores locais para registrarem seu uso. Tres especies foram registradas usando as pontes de corda: o bugio-ruivo (Alouatta guariba clamitans Cabrera, 1940), o gamba-de-orelha-branca (Didelphis albiventris Lund, 1840) e o ourico-cacheiro (Sphiggurus villosus Cuvier, 1823). As pontes de corda mais usadas por maior numero de especies sao aquelas situadas nas areas de maior cobertura florestal e menor area urbanizada, em relacao as pontes menos usadas pelas especies. Nossos resultados indicam que as pontes de corda funcionam como um corredor linear entre os remanescentes florestais, embora nao tenhamos avaliado os efeitos das pontes sobre a sobrevivencia dos individuos, persistencia e demografia dos grupos e fluxo genico na populacao. Alem disso, as pontes podem ser usadas para mitigar o impacto de redes eletricas e rodovias sobre a mortalidade, mas os cabos eletricos tambem devem ser completamente isolados quando presentes.

Habitat Structure Influences the Diversity, Richness and Composition of Bird Assemblages in Successional Atlantic Rain Forests:

This study evaluated the influence of vegetation structure on bird diversity, guilds, and the richness and composition of species in different successional stages of the subtropical Atlantic rain forest. Much of the land that was formerly agricultural in the Brazilian Atlantic rain forest region is now given over to secondary forests. The habitat structure of these successional forests vary and are influenced by time, historical use and local variables, all of which affect bird assemblies. Sampling of bird species was carried out through audio-visual point counts conducted in forests varying from six years after abandonment to old-growth areas. Forests in which the point counts were conducted were further classified into initial, intermediate and advanced stages according to 11 vegetation structural variables, through cluster analyses. The study found that bird richness and diversity were similar between initial and intermediate stages, but higher in advanced areas. Bird species composition differed between the initial and advanced stages, whereas the guild composition of initial forests differed in both intermediate and advanced stages. Late successional forests had more heterogeneous habitats, and some species and guilds were found only in this stage. However, bird diversity and species and guild composition were similar in intermediate and advanced forests, emphasizing the importance of successional forests for conservation efforts, especially when they are located near old-growth forests and conservation units. The recovery patterns of the successional forests studied indicate a great potential for the natural regeneration of the Atlantic rain forest, at least in areas where slash-and-burn agriculture was the previous landuse.

The Need to Improve and Integrate Science and Environmental Licensing to Mitigate Wildlife Mortality on Roads in Brazil

The ongoing expansion of the transportation network is one of the most important threats to tropical ecosystems. In recent years, the Brazilian government is making huge investments in paving and upgrading of the existing road network. It is therefore crucial time to consider how to achieve mitigation of two main road impacts: wildlife mortality and isolation. We discuss the improvement of road ecology research and environmental impact assessments, and recommend the integration of both as a way to achieve effective mitigation. Research oriented toward practical needs is likely to increase use of road ecology in decisions about the impacts of roads and traffic, including the environmental licensing of roads. Well-planned, focused assessments can effectively influence road planning. However, merely improving environmental assessments and research will not be enough to make environmental licensing more effective: there is a need for integration among professions involved in road construction, biodiversity management and conservation for better regulations and enforcement.

Reptile road-kills in Southern Brazil: Composition, hot moments and hotspots

Understanding road-kill patterns is the first step to assess the potential effects of road mortality on wildlife populations, as well as to define the need for mitigation and support its planning. Reptiles are one of the vertebrate groups most affected by roads through vehicle collisions, both because they are intentionally killed by drivers, and due to their biological needs, such as thermoregulation, which make them more prone to collisions. We conducted monthly road surveys (33months), searching for carcasses of freshwater turtles, lizards, and snakes on a 277-km stretch of BR-101 road in Southernmost Brazil to estimate road-kill composition and magnitude and to describe the main periods and locations of road-kills. We modeled the distribution of road-kills in space according to land cover classes and local traffic volume. Considering the detection capacity of our method and carcass persistence probability, we estimated that 15,377 reptiles are road-killed per year (55reptiles/km/year). Road-kills, especially lizards and snakes, were concentrated during summer, probably due to their higher activity in this period. Road-kill hotspots were coincident among freshwater turtles, lizards, and snakes. Road-kill distribution was negatively related to pine plantations, and positively related to rice plantations and traffic volume. A cost-benefit analysis highlighted that if mitigation measures were installed at road-kill hotspots, which correspond to 21% of the road, they could have avoided up to 45% of recorded reptile fatalities, assuming a 100% mitigation effectiveness. Given the congruent patterns found for all three taxa, the same mitigation measures could be used to minimize the impacts of collision on local herpetofauna.