Systematic studies
We compiled 3305 wildlife roadkill records from ten systematic surveys
conducted on Ecuadorian roads. These corresponded to five published
papers, four theses, and one unpublished dataset (Medrano-Vizcaíno et
al. in review). Georeferenced data were available for eight of these
studies and comprised 2744 roadkill records.
Systematic survey studies were not only rare, but also geographically
biased (Figure 1), with three studies conducted in Napo province (Filius
et al., 2020; Medrano-Vizcaíno & Espinosa, 2021; Medrano-Vizcaíno et
al. in review), two in Galápagos (Tanner & Perry, 2007; García-Carrascoet al. , 2020), two in Guayas (González, 2018; Armendáriz, 2022),
two in Manabí (Zavala, 2020; Gaón & Valdez, 2021) and one in Azuay
(Aguilar et al. , 2019).
Collectively systematic studies surveyed only 2.7 % (454.5 km) of the
16,647.65 km of primary and secondary roads in Ecuador (Meijer et
al. , 2018) and yet reported roadkill events for at least 282 species
(i.e., not all individuals had been identified). Seven out of the ten
studies reported data for all tetrapods, while two studies focused on
birds, and one on a single species: the lava lizard Microlophus
albemarlensis. Most records were for reptiles (965 from 76 species; 80
unidentified individuals) and birds (943 from 130 species; 224
unidentified individuals), followed by amphibians (717 from 24 species;
71 unidentified individuals), and mammals (680 from 52 species; 86
unidentified individuals). Roads were monitored using different methods:
driving a car, a bicycle, a motorcycle and walking. Survey intervals
varied between 1.4 and 7 days with the total survey period ranging from
27 to 425 days (Table 1).