ts, P≤0.01 for both).
The response curves (GAMs) of fish richness and abundance also
varied with reef distance (Fig. 4). AIC revealed negative trends for both
abundance and richness, but the first indicated that species richness
decreased exponentially with reef distance, whereas fish abundance
diminished linearly. Response curves (GAMs) of fish abundance with
reef distance were selected by AIC for four families and seven species
(Fig. 5). Except for Haemulidae, which decreased exponentially, the
abundances of Serranidae, Acanthuridae, Chaetodontidae and Scorpaenidae
(the three later groups represented solely by Acanthurus chirurgus,
Chaetodon striatus and S. isthmensis, respectively) decreased linearly
with reef distance. AIC selected GAMs for two haemulid species, and
although negative trends were detected for both species, the abundance
of H. aurolineatum decreased exponentially with reef distance whereas
a linear response was found for H. steindachneri. The abundance of
S. flaviventris also decreased linearly with reef distance, whereas a nonlinear
and non-monotonic positive trend was selected by AIC for
Isopisthus parvipinnis.