Dispersion statistics and sample size estimates for three fish species (Symphodus ocellatus, Serranus scriba and Diplodus annularis) in the Lavezzi Islands Marine Reserve (South Corsica, Mediterranean Sea)
D. Mouillot et al., Dispersion statistics and sample size estimates for three fish species (Symphodus ocellatus, Serranus scriba and Diplodus annularis) in the Lavezzi Islands Marine Reserve (South Corsica, Mediterranean Sea), MAR ECOL-P, 20(1), 1999, pp. 19-34
Citations number
49
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Aquatic Sciences
Journal title
MARINE ECOLOGY-PUBBLICAZIONI DELLA STAZIONE ZOOLOGICA DI NAPOLI I
For the correct management of the future International Marine Park of Bonif
acio, a sampling strategy must be adopted to follow the population fluctuat
ions of certain species of fish. This sampling will be carried out by SCUBA
visual census using the fixed point method. The information to be gleaned
using this method will include estimates of biomass. These data will subseq
uently be used to perform both spatial comparisons between sites and tempor
al comparisons over periods of several years. In order to reveal the existe
nce of statistically significant differences, the sampling strategy adopted
must allow accurate means to be obtained which possess relatively low coef
ficients of variability. The calculation of this optimum sampling depends o
n the spatial distribution of the species examined. The Taylor law (s(2) =
a x (x) over bar(b)), which represents a much utilized mean-variance relati
onship, will be used to compare the aggregation of three species of fish (S
ymphodus ocellatus, Serranus scriba and Diplodus annularis) on two differen
t substrate types (Posidonia oceanica meadows and rocks) and for four sites
in the Lavezzi Islands. The goodness of fit of this law to the biomass dat
a will allow an optimum sampling strategy to be determined for each species
with coefficients of variability of 10 and 25%.