Daily activity profile of the golden mantella in the "Froggotron"-A replicated behavioral monitoring system for amphibians.

Research on threatened species in zoos can provide vital information to inform conservation planning and implementation in the field. This is particularly important for rare and cryptic species with behavior patterns that are difficult to observe in the wild. The Critically Endangered golden mantella (Mantella aurantiaca) is an iconic, endemic frog confined to mid-altitude subhumid forest in Moramanga District, Madagascar. Ecological and behavioral data for this highly threatened species are sparse, and conservation work will need to be informed by both in situ and ex situ research on behavior and habitat preferences. This study utilized environmental information gathered in the field to design a system where behavior and microhabitat use could be measured in captivity. Using replicated climatically controlled chambers (the "Froggotrons"), we analysed the 24-h activity profile of the golden mantella in relation to temperature and humidity. Golden mantellas showed a bimodal pattern of activity during the day with much less activity during the night. Frogs kept at warmer temperatures (20-25°C) were more active than those kept under cooler conditions (16-19°C). However, the bimodal pattern was retained under the different temperatures, although the second peak occurred slightly earlier under warmer conditions. Most activity was observed when humidity levels were above 85%, although less than half of the mantellas were active outside leaf microhabitats during peak periods. These findings can inform ongoing field surveys through determining the optimum times of day to either capture or count golden mantellas for further conservation actions.

Tracking the amphibian pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans using a highly specific monoclonal antibody and lateral-flow technology.

The fungus Batrachochytrium dendrobatidis (Bd) causes chytridiomycosis, a lethal epizootic disease of amphibians. Rapid identification of the pathogen and biosecurity is essential to prevent its spread, but current laboratory-based tests are time-consuming and require specialist equipment. Here, we describe the generation of an IgM monoclonal antibody (mAb), 5C4, specific to Bd as well as the related salamander and newt pathogen Batrachochytrium salamandrivorans (Bsal). The mAb, which binds to a glycoprotein antigen present on the surface of zoospores, sporangia and zoosporangia, was used to develop a lateral-flow assay (LFA) for rapid (15 min) detection of the pathogens. The LFA detects known lineages of Bd and also Bsal, as well as the closely related fungus Homolaphlyctis polyrhiza, but does not detect a wide range of related and unrelated fungi and oomycetes likely to be present in amphibian habitats. When combined with a simple swabbing procedure, the LFA was 100% accurate in detecting the water-soluble 5C4 antigen present in skin, foot and pelvic samples from frogs, newts and salamanders naturally infected with Bd or Bsal. Our results demonstrate the potential of the portable LFA as a rapid qualitative assay for tracking these amphibian pathogens and as an adjunct test to nucleic acid-based detection methods.