National Park Service

Pacific Island Network (PACN)

Benthic Marine Monitoring

Vibrant coral reef at War in the Pacific NHP
Vibrant coral reef at War in the Pacific NHP.
Photo by K.L. Kramer.

Features & Briefs

Monitoring Reports

Monitoring Protocol

Links to Partner Websites

For more information contact: Sheila McKenna

Monitored at:


Description & Rationale

Video: From Polyp to Coral Jungle - Benthic Marine Monitoring

Four parks within the PACN contain rich benthic (sea floor) marine communities home to algae, corals, and other invertebrates. Coral reefs often form the structural framework of nearshore underwater ecosystems and are frequently compared to tropical rainforests in terms of species diversity and the complexity of interactions.

Corals are excellent indicators of the overall health of tropical reef environments because of their importance as primary architectural organisms and their sensitivity to environmental degradation. Primary stressors to coral reefs include diseases, sedimentation, eutrophication, alien species, fishing, storms, and global climate change. The United Nations Environment Programme considers coral reefs a worldwide indicator ecosystem for global climate change.

Benthic Marine monitoring documents the status and long-term condition of coral reefs and is closely linked with the marine fish monitoring protocol, which is conducted at the same time.

Monitoring Objectives

  1. Determine long-term trends in the abundance (density of individuals or percent cover) of sessile marine macroinvertebrate (e.g., corals, sponges) and macroalgal assemblages at fixed and random sites between 10 and 20 meters depth.
  2. Determine trends in benthic small scale topography at randomly selected, fixed stations stratified by habitat or reef zone.
  3. Determine trends in recruitment rate of hard corals (as an assemblage) to uniform artificial surfaces at selected sites on the fore reef between 10 and 20 meters depth.
  4. Determine trends in rate of growth and survival of randomly selected coral colonies of a common, trans-Pacific species (e.g., Pocillopora damicornis, P. verrucosa, Porites lobata) growing at similar depth.
  5. Determine long-term trends in the incidence and severity of coral and algal disease and bleaching.

⇑ To Top of Page

Last Updated: May 15, 2017 Contact Webmaster