Belt Transect Fish Survey Protocol for the U.S. Caribbean and Flower Garden Banks National Marine Sanctuary

Once in the field, the boat captain navigates to previously selected sites using a handheld GPS unit. On-site, divers are deployed and maintain contact with each other throughout the entire census. One diver is responsible for collecting data on the fish communities utilizing the btransect visual census technique over an area of 100m2 (25m length X 4m width). The belt-transect diver obtains a random compass heading for the transect prior to entering the water and records the compass bearing (0-360 degrees) on the data sheet. Where appropriate, the boat can drop a weighted float that will mark the start of the transect. The boat can drop the divers near the float and the team descends down the float line. Dropping a float in the VINP and VICR is not an option so divers are dropped as close to the GPS position as possible. The divers will descend as rapidly, yet safely, as possible to maintain relative proximity to the centroid position. If it becomes apparent that no hardbottom is in the vision of the dive team (i.e., continuous sand or seagrass or limited visibility), then the dive will be terminated and an alternate selected. If hardbottom is observed in the vicinity of the site, then the dive continues as planned- starting on the centroid, or close approximation, and on the predetermined random bearing. Do not alter the predetermined course if the centroid is not on hardbottom or the bearing does not cover hardbottom