Scartella cristata - Amazon S3

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where n is the total number of blennies captured and f represents the number of individuals of each blenny
species (Zar 1996). Species evenness, J ′ , was calculated as
J ′ =
H ′
′
H max
where
H
′ and k represents the number of blenny species (Zar 1996). The mean monthly
max
=
log k
values of H ′ and J ′ for upper, middle, and lower coast stations were calculated and compared using oneway
ANOVAs with Tukey post-hoc tests to identify significant differences (α=0.05).
Catch per unit effort (CPUE), defined as the number of blennies per sampling-hour, was
calculated for constituent species in each collection while mean seasonal CPUE was calculated for each
species. Mean seasonal CPUE was compared across sites and among seasons at each locality with
ANOVA and Tukey post-hoc tests. Analysis of covariance (ANCOVA) was used to determine if
temperature, salinity, turbidity, date, or location correlated with CPUE. Inverse transformation
(transformed CPUE=CPUE -1 ) allowed for all assumptions to be met.
The monthly and overall mean total length were calculated for each species and compared within
locations over time and between locations using ANOVA with Tukey post-hoc tests or t-tests where
appropriate (α=0.05). Length-frequency distributions also were generated for constituent species in each
collection. The total length data could not be reconciled with the assumptions of parametric testing. All
analysis was conducted with log-transformed data.
Mark and recapture: Population size within respective species was estimated using the Petersen equation,
M ( C + 1)
N =
R + 1
where N is the population estimate, M is the number of blennies initially marked, R is the number of
marked blennies recaptured, and C is the total number of fish captured in the second sampling effort (Guy
et al. 1996).
Age and growth: Differences in growth rates of Scartella cristata among the three study sites were
determined through linear regression and ANCOVA. Age-length relationships generated for each site