Autonomous Reef Monitoring Structures

A NOAA diver installing an ARMS unit.
A NOAA diver installing an ARMS unit.

CRED partnered with other scientists from the Census of Marine Life (CoML) Census of Coral Reef Ecosystems (CReefs) to develop Autonomous Reef Monitoring Structures (ARMS). ARMS mimic the complexity of coral reefs to attract/collect colonizing invertebrates and provide a systematic, consistent, and comparable method to monitor cryptic reef diversity.


ARMS provide a systematic, consistent, and comparable method to monitor cryptic reef diversity.

A pristine ARMS sampling unit before deployment
A pristine ARMS sampling unit before deployment
 Newly deployed ARMS
Newly deployed ARMS
 Newly deployed ARMS
Newly deployed ARMS
 ARMS recruitment after 2 years
ARMS recruitment after 2 years

What Purposes do the ARMS Serve?

  • Provides a standard method for taxonomic and molecular analysis to assess invertebrate biodiversity
  • Improves ability to measure/monitor diversity of cryptic organisms globally over time
  • Enhances ecosystem-based management
  • Increases ability to monitor/predict ecological impacts of global climate change, particularly ocean warming and acidification

With an increasing scarcity of trained invertebrate taxonomists, ARMS enable researchers to obtain information using molecular techniques, particularly for small, cryptic organisms that constitute the bulk of reef diversity.

Examples of sessile and mobile organisms collected from individual "plates" or layers of an ARMS unit.

ARMS Global Reach

More than 500 ARMS have been deployed throughout the Pacific, Indian, and Atlantic Oceans

  • 2008-2009 -- CRED conducted 7 Pacific Reef Assessment and Monitoring Program (Pacific RAMP) research cruises to assess coral reef ecosystems and to deploy ARMS:
    • Line and Phoenix Islands
    • American Samoa
    • Northwestern & Main Hawaiian Islands
    • Wake Atoll
    • Guam
    • The Commonwealth of the Northern Mariana Islands (CNMI)
  • 2007-2009 -- CRED deployed ARMS off Honolulu to be used for outreach and a 3-year succession study.
  • 2007-2009 -- CReefs Australia deployed ARMS at Lizard and Heron Islands (GBR) and Ningaloo Reef
  • 2009 -- CRED collaborated with partners on expansion to the following locations:
    • Western Indian Ocean—Reunion, Europa, and Glorieuses Islands
    • Moorea, French Polynesia
    • Florida's northern reef tract and Indian River Lagoon
    • Kimbe Bay in Papua New Guinea
    • Panama (successional study)—deployed by CReefs Smithsonian Node
  • 2010 ARMS were recovered and re-deployed in the following locations:
    • Line and Phoenix Islands
    • American Samoa
    • Northwestern & Main Hawaiian Islands
  • 2010 ARMS were deployed at Sangihe Island in North Sulawesi Indonesia in conjuction with the Bilateral INDEX-SATAL Research Cruise
  • 2010 ARMS were deployed in the Caribbean in Puerto Rico, the Grand Caymans, and the Florida Keys
Locations of current ARMS deployments.
Locations of current ARMS deployments. Click on map to enlarge.

ARMS Retrieval

Upon retrieval, ARMS samples are analyzed molecularly, and when possible, taxonomically. Genetic analysis of ARMS samples using 454 environmental sequencing protocols is currently under development through partnerships with the Smithsonian and California State University. In addition, genetic analysis using MicroArray technology is under development through a partnership with the Hawaiian Institute of Marine Biology. ARMS deployed for outreach purposes will be collected for living reef "Hands-on-ARMS" exhibits/demonstrations.