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APPENDIX 3.

Technical Notes

Sighting Frequency (%SF) is collected using the roving diver method by REEF.

Sighting Frequency is a measure of how often a fish species was observed. It indicates the

percentage of times out of all surveys that the species was recorded. The %SF is calculated as

follows:

S + F + M + A (for each species)

%SF = 100 * --------------------------------------

(# of surveys)

By simultaneously examining the sighting frequency (%SF) and DEN, data summaries can be

interpreted for fish species. The DEN and %SF scores can be multiplied to provide a measure of

species abundance, which includes zero observations.

S2, S6, F4 and F11 FISH ABUNDANCE AND DIVERSITY MEASURES

Key fish families and species in the western Atlantic are: (based on www.AGRRA.org and www.fishbase.org)

· Pomacanthidae (angelfish): High recreational value; targeted for aquarium collection (e.g., Pomacanthus

paru, P. arcuatus, Holocanthus tricolor).

· Acanthuridae (surgeonfish): Key herbivores (e.g., Acanthurus bahianus, A. chirurgus, A. coeruleus).

· Chaetodontidae (butterflyfish): Key herbivores (e.g., Chaetodon capistratus).

· Balistidae (triggerfish): Commercially significant. Key predators of Diadema [e.g., Balistes vetula (queen

triggerfish), B. capriscus (gray triggerfish), Melichthys niger (black durgon), Aluterus scriptus (scrawled

filefish), Cantherhines pullus (orangespotted filefish), C. macrocerus (whitespotted filefish)]

· Lutjanidae (snapper): Commercially significant. Key carnivores (e.g., Lutjanus griseus, L. apodus, L.

mahogoni, Ocyurus chrysurus).

· Haemulidae (grunt): Commercially significant (e.g., Haemulon flavolineatum, H. chrysargyreum, H.

sciurus, H. plumierii).

· Scaridae (parrotfish): Key herbivores (e.g., Sparisoma viride, S. aurofrenatum, Scarus taeniopterus, S.

vetula).

· Serranidae (groupers): Commercially significant. Key carnivores. Epinephelus spp. and Mycteroperca

spp. (e.g., Epinephelus guttatus, E. striatus, Mycteroperca bonaci, M. tigris).

· Lachnolaimus maximus (hogfish): Commercially significant.

· Bodianus rufus (Spanish hogfish): Commercially significant.

· Sphyraena barracuda (barracuda): Commercially significant.

· Carangoides ruber [formerly Caranx ruber (bar jack)]: Commercially significant.

· Microspathodon chrysurus (yellowtail damselfish): Key herbivore.

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