human construction autonomous reef monitoring structure 2024-09-12T12:13:44Z ARMS A human construction which mimic the complex structure of the sea bottom and serve as standardised collectors of marine life. ARMS units are passive monitoring systems originally developed during the Census of Marine Life project for the collection of marine fauna on and near the sea floor. They are stacks of PVC settlement plates that are fixed to each other and to a stable base. They are deployed on marine substrates and colonised by marine species. After a period of time they are recovered and taken apart to see which species colonised them. Using ARMS units allow sampling of reef organisms without destroying or damaging natural sea bottom environments.