Peeing out transmitters Anuran amphibians appear to possess a unique method of removing foreign objects from their body cavities


Meeting Abstract

P2.155  Tuesday, Jan. 5  Peeing out transmitters: Anuran amphibians appear to possess a unique method of removing foreign objects from their body cavities TRACY, C. R.*; CHRISTIAN, K. A.; MCARTHUR, L. J.; Charles Darwin University; Charles Darwin University; Charles Darwin University chris.tracy@cdu.edu.au

While conducting a study involving radio-telemetry of three species of Australian hylid frogs (Litoria caerulea, L. dahlii, Cyclorana australis), we observed what could be a unique mechanism by which frogs can remove foreign objects from their body cavity. Transmitters that we had surgically implanted into the abdominal cavity of frogs were subsequently found frequenly in the bladder when the frogs were retrieved after several months of tracking in the field and the transmitters removed. To bring data to bear on the hypothesis that this observation revealed a potential mechanism for removing foreign objects from the body cavity (a mechanism that would not work for transmitters because they would be too large to be voided through the pelvic girdle), we implanted small (7.8 mm long, 4 mm diameter) plastic beads into the body cavities of L. caerulea and cane toads (Rhinella marinus), and monitored the animals in cages for reappearance of the beads. In L. caerulea, all beads were found in the frog cages within approximately 2-3 weeks; in cane toads, some beads reappeared. This result suggests two things: (1) caution should be employed during telemetry studies when assuming that transmitters found separate from live anurans in the field indicate that predation (or other forms of mortality) separated the animals from their transmitters, and (2) these data document what appears to be a unique mechanism by which foreign objects (e.g., spines or thorns) can be removed from the body cavities of some (or potentially all) anurans.

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