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Biscayne National Park study on reef fish community changes over time
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Reef fish assemblage structure was assessed in 20062007 (recent period) in Biscayne
National Park, Florida, USA , and compared with data collected from 1977 to 1981 (historical
period) from the same location. Substantial differences were observed in reef fish
assemblage structure between periods. Sixty-four percent of species were observed
less frequently in the recent period. Mean species richness per survey declined at
all sites, with declines ranging from 9 to 27. Declines of fishery-targeted species
were also observed and were consistent with but not greater than those observed for
the reef fish assemblage as a whole. The observed declines appeared to be assemblage-wide,
as a majority of species within all trophic guilds examined (spongivores, planktivores,
herbivores, omnivores, invertivores, generalist carnivores, and piscivores) declined
in frequency of occurrence between periods, with declines ranging from 55 of species
for piscivores to 75 for omnivores. Mean number of species per survey declined for
all guilds but herbivores, and ranged from a 14 decline for piscivores to 67 for planktivores.
The declines observed in the present study are conceptually consistent with, but more
extensive than, those recently documented for the Caribbean region as a whole and
with those expected in coral reef systems that are heavily utilized by humans.
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