Patterns and Drivers of Reef Fish Biodiversity in the Florida Keys
National Marine Sanctuary from 1999 - 2016
Abstract
The biodiversity of reef fish in the Florida Keys National Marine
Sanctuary was evaluated in terms of abundance, biomass, evenness,
species richness, Shannon diversity, Simpson diversity, and functional
diversity, using observations collected from 1999 – 2016 by the Reef
Visual Census program. To compare the different diversity indices,
species richness, Shannon diversity, Simpson diversity, and functional
diversity were converted into effective number of species. We examined
the seven indices by level of protection and type of no-take marine
zones and by three habitat strata. The study detected abundance,
biomass, and diversity were significantly greater (except evenness)
inside no-take marine zones compared to areas open to fishing. Smaller
reserves had higher abundance, biomass, and richness values than larger
reserves and areas open to fishing, but had moderately higher diversity
values. This may be attributed to a few species with many individuals
that are dominant inside and outside no-take marine zones. Surprisingly,
none of the indices were significantly different (except for functional
diversity) between the larger Ecological Reserve and areas open for
consumption. This may be due to spillover effects. Furthermore, the
no-take marine zones only explained a small proportion of total percent
deviance in the indices. Habitat type had a greater influence on
patterns in composition and diversity where high relief reef habitats
had the greatest abundance, biomass, and diversity indices. Based on our
results managers should prioritize preserving high relief reefs through
a network of small reserves to enhance reef fish composition and
biodiversity.