Road-killed toads as a non-invasive source to study feeding ecology of migrating population

Abstract

Little is known about amphibian feeding activity during post-hibernation migration to breeding ponds. It is widely assumed that explosively breeding anurans do not feed between the end of hibernation and completion of breeding. We investigated the potential for using road-killed common toads Bufo bufo in order to find out whether migrating toads feed during this period and to assess the content of their stomachs. We collected a total of 416 toad carcasses during spring migration from two study sites in southwestern Poland, of which 246 (59%) carcasses contained intact digestive tracts (stomach and intestines). In 97 of these (39%), we found stomach contents composed of invertebrate remains, whereas the intestines of 180 (73%) toads contained already-digested animal remains. We found no significant differences between males and females, with or without prey, or between individuals at two different study sites. We found a total of 290 prey items, classified to the lowest possible taxonomic rank. Formicidae (Insecta: Hymenoptera) was the most abundant taxon; however, based on the dominance index, common toads could not be classified as fully polyphagous. The Jaccard and Bray-Curtis indices showed a generally low level of intersexual similarity in diet composition at both study sites as well as between males and females. Our results show that road-killed toads can be used to study foraging activity and diet composition; however, this approach should be tested on more species.

Effects of invasive jumping worms (Amynthas spp.) on microhabitat and trophic interactions of native herpetofauna

“…This aligns with prior findings that toads predominantly consume arthropod prey (Smith and Bragg 1949;Bellocq et al 2000;Bolek and Coggins 2000), but may opportunistically prey on earthworms (Bush 1959). Earthworms have also been recorded in diets of toad species in the related genus Bufo (Evans and Lampo 1996;Vallvé and Sánchez-Iglesias 2018;Kolenda et al 2019). Our sample size of American toads was relatively small, particularly in the Amynthasinvaded area, so we cannot say with much certainty whether or not American toads are consuming Amynthas in the field.…”

Dead snakes and their stories: morphological anomalies, asymmetries and scars of road killed Dolichophis caspius (Serpentes, Colubridae) from Romania

“…Road traffic does not only impact snakes, but also other animals (Ashley and Robinson 1996;Glista et al 2007;Baxter-Gilbert et al 2015;Ciolan et al 2017). The high number of mortalities from different animal groups has permitted road mortalities to be employed as study material for feeding ecology (Drygala and Zoller 2013; Kolenda et al 2019), phylogeography (Grill et al 2009;Horcajada et al 2018), temporal trends in populations (Meek 2020) and faunistic studies (Gonzáles-Gallina et al 2016;Teodor et al 2019).…”