Global ARMS Program

Autonomous Reef Monitoring Structures (ARMS) are standardized 3D collectors of marine life. They are stacks of plates that mimic the complex structure of the sea bottom that is hard to sample without destroying natural habitat. Think of them like mini-hotels that provide hard surfaces and nooks and crannies that sea creatures like to live on and among.

ARMS act as biological weather stations. They are deployed for a period of time, then recovered by a team and taken apart to see who moved in. ARMS recruit local species to provide a flavor of that particular region. This standard census allows researchers to compare one place to another or how one place changes over time, based on these ARMS communities.

ARMS are located in clusters all over the world, from the poles to the tropics, and from the intertidal to the deep sea. They are usually deployed in triplicate to provide statistical power and replication, and to test the level of variation at any one site. Check out our map to see where researchers have deployed ARMS. 

ARMS can tell us how marine communities respond to different ocean conditions or how management practices affect ocean health. For instance, ARMS can demonstrate the effectiveness of marine protected areas or the impact of ocean stressors like pollution or ocean acidification. Knowing how marine species will respond to different ocean states can help us predict and plan actions for a healthier planet.