Time-lapse cameras were used to describe how platypus activity patterns changed during a cease-to-flow event lasting nearly 2 months along a normally reliably flowing Tasmanian stream. The findings indicate that the platypus’s ability to survive extended dry periods relies on its having access to sufficiently large and productive refuge habitats. (Photograph by Simon Roberts.)

Historical records can provide invaluable insights into long-term changes in marine communities, but they are limited by the methods used at the time. In this study, we have highlighted how the marine life at a popular site in Sydney has changed over 58 years, owing to the efforts of citizen scientists. (Image credit: Jordana Costa.)