Dispersal distances of radio-tracked cane toads in French Guiana

Like most invasive species, cane toads have attracted less research in
their native range than in invaded areas. We radio-tracked 34 free-ranging
toads in French Guiana, a source region for most invasive populations,
across two coastal and two rainforest sites. Coastal toads generally
sheltered in pools of fresh or brackish water but nocturnally foraged on
beaches, whereas rainforest toads sheltered in forested habitats, moving
into open areas at night. Over five days of monitoring, native toads
frequently re-used shelters and moved little between days (means = 10–63
m/site) compared to invasion-front toads from Australia (~250 m). Larger
toads moved less between days, but displaced in more consistent
directions. At night, foraging toads travelled up to 200 m before
returning to shelters. Foraging distance was related to body condition at
coastal sites, with toads in poorer body condition travelling farther.
Rain increased the probability of coastal toads sheltering in the dry
habitats where they foraged. Dispersal and rainfall were lower at coastal
sites, and the strategies utilized by coastal toads to minimize water loss
resembled those of invasive toads in semi-desert habitats. This global
invader already exhibits a broad environmental niche and substantial
behavioural flexibility within its native range.