Rl. Sherman et al., A preliminary examination of depth associated spatial variation in fish assemblages on small artificial reefs, J APP ICHTH, 15(3), 1999, pp. 116-121
Citations number
12
Categorie Soggetti
Aquatic Sciences
Journal title
JOURNAL OF APPLIED ICHTHYOLOGY-ZEITSCHRIFT FUR ANGEWANDTE ICHTHYOLOGIE
Small concrete artificial reef modules (hemisphere-shaped, approximately 1.
3 m diameter, 1 m high) were placed at two sites, eight modules per site. T
he sites were in 7 m and 21 m of water, 1.6 km apart, off the coast of sout
heast Florida, USA. The reefs were censused monthly for fish over a 19-mont
h period. Species, number of fish, and estimated total length of each indiv
idual were recorded by divers using SCUBA. After the monthly census, all fi
sh were removed from the reefs with a piscicide. A total of 88 species were
recorded in the study, with significantly greater diversity on the deep re
efs (monthly mean of 7.6 versus 3.0 shallow, P < 0.001, ANOVA). There were
also significantly more biomass (calculated from length), and more Large fi
sh (>5 cm) on the reefs at 21 m than at 7 m (P < 0.001). There were more sm
all fish at the shallow site (P < 0.05). Although it is not clear what vari
able(s) associated with the two depths is responsible for the differences,
these results highlight the potential differences in artificial reef and am
bient environment interactions within a localized area.