The Maud Island frog is one of the rarest frogs on the planet, and also the longest lived—a monitoring programme set up by Ben Bell in the mid-1970s has tracked the same individuals up for 50 years, some of them staying within a 20–30 square metre area for their entire life. Here, rangers catch, identify and measure frogs at night (they’re nocturnal) as part of that continuing half-century of research.