Larger body size at metamorphosis enhances survival, growth and performance of young cane toads (Rhinella marina)

PLoS One. 2013 Jul 29;8(7):e70121. doi: 10.1371/journal.pone.0070121. Print 2013.

Abstract

Body size at metamorphosis is a key trait in species (such as many anurans) with biphasic life-histories. Experimental studies have shown that metamorph size is highly plastic, depending upon larval density and environmental conditions (e.g. temperature, food supply, water quality, chemical cues from conspecifics, predators and competitors). To test the hypothesis that this developmental plasticity is adaptive, or to determine if inducing plasticity can be used to control an invasive species, we need to know whether or not a metamorphosing anuran's body size influences its subsequent viability. For logistical reasons, there are few data on this topic under field conditions. We studied cane toads (Rhinella marina) within their invasive Australian range. Metamorph body size is highly plastic in this species, and our laboratory studies showed that larger metamorphs had better locomotor performance (both on land and in the water), and were more adept at catching and consuming prey. In mark-recapture trials in outdoor enclosures, larger body size enhanced metamorph survival and growth rate under some seasonal conditions. Larger metamorphs maintained their size advantage over smaller siblings for at least a month. Our data support the critical but rarely-tested assumption that all else being equal, larger body size at metamorphosis is likely to enhance an individual's long term viability. Thus, manipulations to reduce body size at metamorphosis in cane toads may help to reduce the ecological impact of this invasive species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Australia
  • Body Size*
  • Bufo marinus / growth & development
  • Bufo marinus / physiology*
  • Environment
  • Feeding Behavior
  • Female
  • Introduced Species
  • Male
  • Metamorphosis, Biological*
  • Motor Activity
  • Survival Rate

Grant support

The work was funded by the Australian Research Council, the Australian Government, the National Council on Science and Technology of Mexico (CONACyT), and the University of Sydney. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.