Underwater writing slates were used to record the different species adhering to the top, side and interior roof of pipes over time. Counting the interior surface of pipes took considerable flexibility on the part of the diver.
Photographer: Dr. James P. McVey
Affiliation: NOAA Sea Grant Program
Location: Pokai Bay, Oahu
Subject: Coral Reefs
Subject: Marine Biologist
Subject: Artificial Reef