Now you see me, now you don't

Abstract

The montane litter frog (Leptobrachium montanum) is a medium-sized, stocky frog that tends to sit among leaf litter, where its camouflage protects it from predators. The species is endemic to the island of Borneo and can be found at medium-high elevations in Indonesia, Brunei, and Malaysia. This amphibian is listed by the IUCN as a species of least concern due to its widespread geographic distribution and relative abundance across a number of locations. The frogs have large eyes that are perfect for hunting in the dark, which is when they are often encountered along roads and trails. L montanum individuals are also unmistakable during nighttime amphibian surveys due to the brilliance of their eyeshine. Montane litter frogs exhibit an interesting anti-predatory behavior that is often seen when they are approached by humans. The frogs will stand alert with their heads held high, and when they detect a potential threat, they crouch down in the leaf litter to mimic dead leaves. They quickly move their head to the ground and tuck in their front legs; the eyes usually remain open. Due to encroachment of humans in their preferred habitat, leafy hiding spots are not always available – so how effective is this behavior at preventing predation in other environments? Does crouching on concrete still help to break up their form? And with an ever-increasing presence of humans around them, it's also worth asking: can they see us as well as we see them?