ORIGINAL PAPER The impact of lungworm parasites on rates of dispersal of their anuran host, the invasive cane toad Gregory P. Brown . Crystal Kelehear . Ligia Pizzatto . Richard Shine Received: 23 July 2015 / Accepted: 24 September 2015 Ó Springer International Publishing Switzerland 2015 Abstract Translocation of native-range parasites to control invasive species is effective only if the parasite substantially impairs either the viability or dispersal rate of the invasive host. Lungworms (Rhabdias pseudosphaerocephala) of cane toads (Rhinella mar- ina) were introduced to Australia from the toad’s native range, along with the toads, and have been suggested as a potential biocontrol of invasive toads due to various negative impacts on toad viability. We conducted two radio-telemetry studies on a tropical floodplain to specifically assess the parasite’s impact on toad dispersal. First, a retrospective correlative analysis of data from field-collected animals showed that toads infected with lungworms moved farther, not less, than uninfected conspecifics. Second, an exper- imental study (comparing movements of experimen- tally infected toads vs. uninfected controls) showed that lungworms did not modify rates of toad dispersal. In addition, experimental infection with lungworms did not elicit an immune response substantial enough to influence dispersal behaviour. Thus, we conclude that increasing lungworm densities at the invasion front as an attempt at biocontrol would not slow down the spread of cane toads. Keywords Anuran Á Bufo marinus Á Host-parasite Á Invasion front Á Invasive species Introduction The devastating ecological impacts of many invasive species have prompted efforts to control the invaders. One of the most successful strategies has involved identifying natural enemies (such as pathogens/para- sites, or consumers/predators) that curtail the inva- der’s abundance in its native range, but were left behind during the process of introduction to (or range expansion within) the invader’s new home (Prenter et al. 2004; Torchin et al. 2003; Torchin and Mitchell 2004). If translocated to the introduced range, those enemies may curtail invader expansion (Dobson 1988; Messing and Wright 2006; Torchin and Mitchell 2004). For example, invasive-range populations of the prickly-pear cactus (Opuntia stricta) in Australia were decimated by the introduction of the moth Cacto- blastis cactorum (Dodd 1959; Julien et al. 2012). Nonetheless, the history of attempts at biocontrol also contains less successful remediations (Messing and Wright 2006; Saunders et al. 2010). Potentially, the translocated parasite or disease might not substantially affect the invader; and/or have collateral impacts on G. P. Brown (&) Á C. Kelehear Á L. Pizzatto Á R. Shine School of Biological Sciences, A08, University of Sydney, Sydney, NSW 2006, Australia e-mail: gregory.brown@sydney.edu.au C. Kelehear Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama, Republic of Panama 123 Biol Invasions DOI 10.1007/s10530-015-0993-1