Capture of smooth newts (Lissotriton vulgaris) and great crested newts (Triturus cristatus) correlates with the lunar cycle

This study examined the hypothesis that numbers of newts captured were correlated with the phase of the moon. During the spring of 2008 smooth newts and great crested newts were captured in bottle traps laid in two ponds at Riseholme Park, University of Lincoln, UK. Highest rates of capture for smooth newts were either side of the new moon but for great crested newts the highest rate was immediately before the new moon. Identification of individuals showed that during the observation period smooth newts regularly moved between aquatic and terrestrial habitats, but great crested newts appeared to leave ponds and did not return. This is the first report that numbers of newts captured are affected by the lunar cycle. Activity during the darkest nights may limit the risk of predation as individuals leave breeding ponds to forage on land or to move between ponds. These results have implications for surveys of newt breeding sites because lack of individual identification and trapping events at the wrong time of the month can both seriously undermine estimates of population sizes.