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Abstract:The effects of habitat fragmentation and deforestation are exacerbated by some elements, such as roads and power lines, which may become filters or barriers to wildlife movements. In order to mitigate mortality and restore connectivity, wildlife passages are being constructed as linear corridors. The installation of these mitigation measures must be followed by systematic monitoring, in order to evaluate their use and effectiveness, to assist in their management, and to convince stakeholders of their value. In this paper we present the results of a monitoring study of the use of rope overpasses developed near a protected area in Porto Alegre, southern Brazil. The canopy bridges were installed by the Urban Monkeys Program in places where electric hazards and road-kills of brown howler monkeys (Alouatta guariba clamitans Cabrera, 1940) were recorded. Camera traps were installed at each bridge, and local people were selected and trained to monitor overpass use over 15 months, from August 2008 to October 2009. Three species were recorded using canopy bridges: brown howler monkey (Alouatta guariba clamitans Cabrera, 1940), white-eared opossum (Didelphis albiventris Lund, 1840) and porcupine (Sphiggurus villosus Cuvier, 1823). Rope bridges with the highest number of species recorded had more forest cover and lower urban area around them than overpasses little used. Our results indicate that overpasses, in Porto Alegre, work as a linear corridor between forest remnants, although the outcomes for individual survival, group persistence, population demography or gene flow have not been measured. Furthermore, canopy bridges may be important to mitigate the impact of roads and power lines on wildlife, but electric cables also need to be completely isolated when present, to warrant animals' physical integrity. Resumo: Os efeitos do desmatamento e da fragmentação de hábitats são exacerbados por elementos como rodovias e redes elétricas, 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 têm sido construídas como corredores lineares. A instalação dessas estruturas deve ser seguida de monitoramento sistemático, visando à avaliação de seu uso e efetividade e a geração de informações para seu manejo e para convencer os tomadores de decisão 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 imediações da Reserva Biológica do Lami José Lutzenberger, em Porto Alegre, Brasil. As pontes de dossel foram instaladas pelo Núcleo de Extensão Macacos Urbanos em locais com registros de atropelamentos e choques elétricos de bugios-ruivos (Alouatta guariba clamitans Cabrera, 1940). Instalamos armadilhas fotográficas em cada ponte e selecionamos moradores locais para registrarem seu uso. Três espécies foram registradas usando as pontes de corda: o bugio-ruivo (Alouatta guariba clamitans Cabrera, 194...

The evaluation of road-kill spatial patterns is an important tool to identify the priority of locations for mitigation measures aiming to reduce wildlife mortality on roads. Single-target or multi-species approaches are usually adopted on the implementation of such measures, although their success must be assessed. We aim to test if road-kill hotspots are coincident among different vertebrate groups. If this proves to be right, data on accidents from one group could be used to plan measures applicable to other groups. We identified hotspots using five different grouping criteria: vertebrate Classes (reptiles, birds or mammals), body size (large or small), species commonness (common or rare), type of locomotion (flying or non-flying), and time of activity (nocturnal/crepuscular or diurnal). We analyzed data from road-kill surveys on four roads in southern Brazil, each with at least one year of monitoring. We performed a modified Ripley's K-statistic to recognize scales of road-kill aggregation, and we carried out a hotspot analyses to identify the location of road-kill aggregations for each group described above on each road. To test for similarity in hotspot location among different groups we performed an association test using correlation as the resemblance measure. Hotspot analyses and association tests were done using different spatial scales to evaluate the effect of scales on similarities. Correlation results between groups presented low values at small scales although they had a tendency to increase with raising scales. Our results show that road-kill hotspots are different among groups, especially when analyzed on small scales. We suggest that, for a successful biodiversity approach to mitigation, one should first select general hotspots on large scales and then identify specific hotspots on small scales to implement specific measures. These findings are relevant in a context of existing road networks, where mitigation measures are being planned to reduce impact on wildlife.

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.

Summary The effectiveness of measures installed to mitigate wildlife road‐kill depends on their placement along the road. Road‐kill hotspots are frequently used to identify priority locations for mitigation measures. However, in situations where previous road mortality has reduced population size, road‐kill hotspots may not indicate the best sites for mitigation. The purpose of this study was to identify circumstances in which road‐kill hotspots are not appropriate indicators for the selection of the best road‐kill mitigation sites. We predicted that: (i) road‐kill hotspots can move in time from high‐traffic road segments to low‐traffic segments, due to population depression near the high‐traffic segment caused by road mortality; (ii) this shift will occur earlier for more mobile species because they should interact more often with the road; (iii) this shift can occur even if the low‐traffic segment runs through lower quality habitat than the high‐traffic segment. To test these predictions, we simulated population size and road‐kill over time for two populations, one exposed to a road segment with high traffic and the other to a road segment with low traffic. Our simulation results supported Predictions 1 and 3, while Prediction 2 was not supported. Synthesis and applications. Our results indicate that, for new roads, road‐kill hotspots can be useful to indicate appropriate sites for mitigation. On older roads, road‐kill hotspots may not indicate the best sites for road mitigation due to population depression caused by road mortality. Direct measures of the road impact on the population, such as per capita mortality, are better indicators of appropriate mitigation sites than road‐kill hotspots.

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