Reef Life Survey: Global reef fish dataset

Quality Control

Data in the RLS global reef fish dataset have been collected by a combination of experienced scientists and skilled recreational divers, with all divers having either substantial prior experience in reef fish surveys or extensive training in the RLS methods. Quality control procedures are described in detail in Edgar & Stuart-Smith 2014 and results of an analysis of data quality differences between volunteer divers and professional scientists are presented in Edgar & Stuart-Smith 2009.

Method steps

1. Line transects 50 m in length are laid along a depth contour. Fishes are surveyed in two 5 m wide by 5 m high bands or ("blocks"), parallel with the 50 m transect line. During the fish survey, the number and estimated size-category of all fishes sighted within 5 m blocks either side of the transect line, and within a 5 m high ceiling (and 5 m deep floor if applicable, see section on methods for surveying walls in appendix 2, in manual) is recorded as the divers swim slowly along the block. Size-classes of total fish length (from snout to tip of tail, or longest distance, including for stingrays) used are 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 20.0, 25.0, 30.0, 35.0, 40.0, 50.0, 62.5 cm, and above. Lengths of fish larger than 62.5 cm should be estimated to the nearest 12.5 cm and individually recorded. GPS location, date, time, depth and visibility are also recorded. See link to the Methods Manual: A Standardized Survey Procedures for Monitoring Reef Ecosystems, for more information.