Wrt. Darwall et Nk. Dulvy, AN EVALUATION OF THE SUITABILITY OF NONSPECIALIST VOLUNTEER RESEARCHERS FOR CORAL-REEF FISH SURVEYS - MAFIA ISLAND, TANZANIA - A CASE-STUDY, Biological Conservation, 78(3), 1996, pp. 223-231
Trials are described for testing and validating the use of non-special
ist volunteer divers or visual censusing of reef fish populations. Vol
unteers showed significant improvement between two censuses in identif
ying 56 species in 30 genera. Thus, after 11 additional dives, the los
s of precision compared with an experienced 'control' diver was reduce
d from 13% to 0.6%. In the second census there was no loss in consiste
ncy caused by the use of groups of divers rather than single divers. E
ven in the early stages of training the level of precision was suffici
ent to detect changes in composition at the trophic level. Coloured ca
nvas strips were used as model 'fish' for estimating lengths underwate
r. After three trials divers were able to estimate lengths with an 80%
accuracy in relation to the true distribution. Copyright (C) 1996 Els
evier Science Limited