Using DNA barcode to relate landscape attributes to small vertebrate roadkill

Abstract

Large vertebrates are the main focus of roadkill studies because their greater size facilitates taxonomic identification and the collection of statistical data. However, these studies fail to effectively include and identify small vertebrates and correlate roadkill events with the surrounding landscape. Here we showed the effectiveness of molecular data to identify small vertebrate roadkill, and we correlated landscape structure attributes with the location of roadkill for functional groups of varying mobility. The extraction of DNA from roadkilled individuals was followed by the amplification of two mitochondrial genes. We compared each DNA sequence to a database and used the highest similarity values for species identification. The species were classified according to their taxa and degree of mobility: birds, reptilia and amphibia with low and intermediate movement capability. After calculating the landscape attributes for each roadkill point, we used a competing model approach based on Akaike Information Criteria to determine which landscape variable best explained the occurrence of roadkills. Combining molecular and morphological characteristics, we identified 82.93% of the roadkilled animals. DNA barcoding allowed the identification of 310% more specimens than by morphological characteristics alone. Roadkilled birds with intermediate movement capability were strongly influenced by dominated areas by agriculture and sugar cane monocultures. Roadkilled reptiles with low movement capability were positively correlated with the presence of forest remnants, while those with intermediate movement capability seemed to be more Communicated by Kirsty Park.

Roadkill records of reptiles and birds in Cerrado and Pantanal landscapes

“…First geographic records (FGR) and new roadkill records (NRR) for reptile and bird species were verified from the literature. We compared our dataset to data collected by De Souza et al (2014) from the same highway (BR-262) and data of road-killed reptiles and birds from other Brazilian roads (Novelli et al 1988, Prado et al 2006, Silva et al 2007, Coelho et al 2008, Hengemühle and Cademartori 2008, Cunha et al 2010, Hartmann et al 2011, Ramos et al 2011, Santana 2012, Santos et al 2012, 2014Carvalho et al 2014, Klippel et al 2015, Machado et al 2015, Almeida et al 2016, Braz and França 2016, Deffaci et al 2016, Saranholi et al 2016, Steil et al 2016, Corrêa et al 2017, Miranda et al 2017, Rodríguez-Castro et al 2017, Viturino and Graciolli 2017, Gonçalves et al 2018, Ramos-Abrantes et al 2018.…”

Spatio-temporal variation of roadkills show mass mortality events for amphibians in a highly trafficked road adjacent to a national park, Costa Rica

“…Seasonal differences in mortality rate were also observed for tropical bird species in two federal highways in Southern Brazil (Alvez da Rosa & Bager, 2012). In addition, the spatial configurations and attributes of roads within landscapes and their distance to wildlife habitats may influence the rate at which animals are killed (Glista, DeVault, & DeWoody, 2008;Fahrig & Rytwinski 2009;Rodríguez-Castro et al, 2017). Thus, roads in close proximity to natural habitats are expected to have greater impacts on wildlife than those located away from natural habitats.…”

“…However, González-Gallina, Benítez-Badillo, Rojas-Soto and Hidalgo-Mihart (2013) found that mammals were the most frequently killed on roads in grassland in Mexico, and that 95 % of the 827 mammals found were small rodents. In addition, accurate accounts and precise identification of small bodies were achieved recently using DNA barcoding in Brazil (Rodríguez-Castro, Ciocheti, Ribeiro, Ribeiro, & Galetti Jr., 2017).…”

“…However, González-Gallina, Benítez-Badillo, Rojas-Soto and Hidalgo-Mihart (2013) found that mammals were the most frequently killed on roads in grassland in Mexico, and that 95 % of the 827 mammals found were small rodents. In addition, accurate accounts and precise identification of small bodies were achieved recently using DNA barcoding in Brazil (Rodríguez-Castro, Ciocheti, Ribeiro, Ribeiro, & Galetti Jr., 2017).Although roadkills are commonly reported as an average number per km, dead animals are not distributed evenly along the roads. Brockie (2007) found that a disproportionate number of possums (Trichosurus vulpecula) and hedgehogs (Erinaceus europaeus) were killed in or near bridges in New Zealand, a spatially aggregated pattern that the author termed roadkill "blackspots".…”

“…A review by Taylor and Goldingay (2010) on roadkill studies around the world showed a strong bias towards temperate zones. The authors found that 51 % of studies were conducted in North America, 25 % in Europe, 17 % in Australia and only 7 % in other countries (Coelho, Kindel, & Coelho, 2008;Cáceres et al, 2010;González-Gallina et al, 2013;Rodríguez-Castro et al, 2017). Such a distinct geographical bias is holding back the development of effective conservation policy in the tropics, where large expanses of pristine tropical rain forest are being subjected to road construction (Laurance, Goosem, & Laurance, 2009).…”