2005 STATE OF CORAL REEF REPORT.pdf - Mote Marine Laboratory

Historical data collected by previous
investigators provide comparative
information, although comparative
abundance data frequently are
not available. For example, Randall
(1967) collected many species of
fish for his landmark studies of Caribbean
reef fishes around St. John
from 1958-1961. Although few were
quantitative, Randall’s studies provided
relative abundance and size
structure of species. Large groupers
frequently captured by Randall
in 1958-61 were in very low relative
abundance in the 1989-2000 monitoring
data (Figure 4.22). The two
smaller-sized groupers, red hind and
coney, were much more common in
the recent monitoring data. These
long-term comparisons suggest that
large changes have occurred in Virgin
Islands fisheries, similar to patterns
observed throughout the Caribbean.
Over-exploitation by fisheries
certainly has been a strong contributor
to the observed declines.
The most apparent temporal signal
in reef fish assemblage characteristics
around St. John over the 12year
monitoring period resulted from
the influence of large storm events
(Beets and Friedlander, 2003). The
Virgin Islands have been greatly influenced
by numerous large storms
since 1988. Data were separated
into two periods (1989-1994 and
1996-2000) representing the poststorm
recovery periods following the
two major storms affecting St. John
(Hurricane Hugo, Sept. 1989; Hurricane
Marilyn, Sept. 1995). As data
for 1995 were collected just prior to
Hurricane Marilyn, those data were
excluded from analysis. Assemblage
characteristics (species richness,
abundance, and biomass) showed
statistically significant increases during
the five-year period following
Hurricane Hugo (1989, Figure 4.23).
While species, number of individuals,
and biomass all increased following
Hurricane Marilyn (1995), none of
these trends were significant for the
The State of Coral Reef Ecosystems of the U.S. Virgin Islands
Figure 4.22. Comparison of the relative abundance of groupers collected by Randall
from 1958-1961 and groupers sampled during 1989-2000 around St. John. Source:
Beets and Friedlander, 2003.
Figure 4.23. Trends in assemblage characteristics during the five years following two
hurricanes which affected St. John (Hugo, Sept. 1989; Marilyn, Sept. 1995). Average
values for each of the four reference sites are represented by circles for each year.
Regression lines and coefficients were obtained from linear regression analysis. Data
for 1995 were excluded from these analyses. Source: Beets and Friedlander, 2003.
U.S. Virgin Islands
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