Fig 1.
History of introductions of Cane Toads (Rhinella marina) to Japanese islands (in bold).
In Iriomote, Cane Toads were transported from Ishigaki as accidental entries. Based on [4,21–23].
Fig 2.
Growth and development of Cane Toad tadpoles at day 10 following exposure as embryos to chemical cues of older conspecific tadpoles.
The panels show impact of exposure to older tadpoles on a) body mass, and b) developmental stage (Gosner 1960 [38]) of embryos that were exposed to cues from tadpole of four groups (Wild Group 1, 2, and Lucrin Group1, 2). The graphs show mean values with associated standard errors.
Fig 3.
Growth and development of Cane Toad tadpoles at day 10 day following exposure as embryos to chemical cues of older tadpoles of native frog species (F. sakishimensis, R. owstoni, and M. ornata).
The panels show impact of exposure to native frog tadpoles on a) body mass, and b) developmental stage (Gosner 1960 [38]) of Cane Toad embryos. The graphs show mean values with associated standard errors.
Fig 4.
Growth and development of tadpoles of the Ornate Narrow Mouthed Frog M. ornata at day 10 day following exposure as embryos to chemical cues of older Cane Toad tadpoles (Wild Group 1 and 2) and native frog tadpoles (F. sakishimensis and M. ornata).
The panels show impact of exposure to tadpoles on a) body mass, and b) developmental stage (Gosner 1960 [38]) of Ornate Narrow Mouthed Frog embryos. The graphs show mean values with associated standard errors.
Fig 5.
Odds ratio for attraction responses of Cane Toad tadpoles to cues from conspecific eggs and adult toxin.
The graph shows mean odds ratios with 95% confidence intervals. The horizontal line at Odds Ratio of 1.0 represents the Control; treatments whose 95% confidence intervals do not overlap this line are significantly different from the Control.
Table 1.
Results of statistical analysis on data for position within the acoustic-testing apparatus for male Cane Toads after 10 minutes.
We used Rayleigh’s tests to assess the directional mean of toads, and Dunnett’s tests to compare the distance from speaker in the pink noise (Control) treatment versus the other four sound types.
Fig 6.
Angle that Cane Toads approached a variety of acoustic stimuli after 10 minutes.
The panels show responses of (a) male toads (upper panel), and (b) female toads (lower panel). Sample size is given in parentheses. The black square indicates the position of the speaker. Each black small circle shows the position of a toad after ten minutes. * P<0.05.
Fig 7.
Phonotactic responses of Cane Toads (Rhinella marina) to a variety of acoustic stimuli, based on the toad’s distance to the speaker after 10 minutes.
The panels show responses of (a) male toads, and (b) female toads. All graphs show mean values and associated standard errors. * P<0.05.
Table 2.
Results of statistical analysis of data for position within the acoustic-testing apparatus for female Cane Toads after 10 minutes.
Statistical methods were same as described in the caption to Table 1.