The impact of transportation and translocation on dispersal behaviour in the invasive cane toad

Abstract

Biological invasions transport organisms to novel environments; but how does the translocation process influence movement patterns of the invader? Plausibly, the stress of encountering a novel environment, or of the transport process, might induce rapid dispersal from the release site-potentially enhancing (or reducing) invader success and spread. We investigated the effect of transportation and release to novel environments on dispersal-relevant traits of one of the world's most notorious invaders, the cane toad (Rhinella marina). We collected toads in northern New South Wales from heath and woodland habitats, manipulated the level of transport stress and either returned toads to their exact collection point (residents) or reciprocally translocated them to a novel site. Both translocation and the level of transport stress drastically altered toad dispersal rates for at least 5 days post-release. Translocated toads (depending on their level of transport stress and release habitat) moved on average two to five times further per day (mean range 67-148 m) than did residents (mean range 22-34 m). Translocated toads also moved on more days, and moved further from their release point than did resident toads, but did not move in straighter lines. A higher level of transport stress (simulating long-distance translocation) had no significant effect on movements of resident toads but amplified the dispersal of translocated toads only when released into woodland habitat. These behavioural shifts induced by translocation and transportation may affect an invader's ability to colonise novel sites, and need to be incorporated into plans for invader control.

Captivity induces large and population‐dependent brain transcriptomic changes in wild‐caught cane toads (Rhinella marina)

“…Enrichment for these GO terms has been repeatedly found in studies investigating gene expression changes associated with phenotypic differences, for example, between Chinese and western pig breeds (Zhang et al, 2018), sympatric whitefish (Coregonus clupeaformis) populations (Hebert et al, 2013), dietary restricted fruit flies (Katewa et al, 2012), or mice selected for increased voluntary wheel-running behaviour (Kavushansky et al, 2018). This suggests a strong influence of captivity on toad behaviour, as has been previously reported (Gruber et al, 2018;Pettit et al, 2017).…”

Reproductive behavior drives female space use in a sedentary Neotropical frog

“…To date, the vast majority of studies on amphibian space use focused on migratory behavior of temperate amphibians characteristic of the seasonal and lifetime spatio-temporal scale, e.g., the synchronized mass migration from winter habitats to breeding sites, return migrations of adults between different parts of the habitat or dispersal of juveniles (e.g., Heusser, 1968;Sztatecsny & Schabetsberger, 2005;Sinsch et al, 2012) (for reviews see Richards, Sinsch & Alford, 1994;Sinsch, 2010;Pittman, Osbourn & Semlitsch, 2014;Sinsch 2014). Tropical amphibians show much more diverse reproductive and spatial behaviors, such as long-term site fidelity, territoriality, courtship, and offspring transport (Wells, 2007;Summers & Tumulty, 2014) but very few studies have quantified the fine-scale movements of tropical amphibians (Brown et al, 2006;Oliveira et al, 2016;Ward-Fear, Greenlees & Shine, 2016;Pettit, Greenlees & Shine, 2017).…”

Habitat type and structure affect trap capture success of an invasive snake across variable densities

“…Due to aberrant behavior often associated with translocation (Pettit et al. ), or differences in behavior and habitat on other islands, this assumption may not be so straightforward. Overall, however, habitat structure and forest types are largely similar across the Mariana Islands (Fosberg ).…”