The fish community at 40 m presented a trophic structure strongly associated with a
plankton food web, consistent with observations at 30 m. The top four most abundant
fishes within belt-transects (blue and sunshine chromis, masked goby and creole
wrasse) are known to feed mostly on zooplankton (Randall, 1967). The combined
zooplanktivorous assemblage represented at least 80 % of the total fish individuals
surveyed within belt-transects at 40 m. The fact that most of these fishes (except creole
wrasse) live close to the benthic reef habitat, suggests that demersal zooplankton plays
an important role in the trophic dynamics of this system.
s previously stated for the 30 m depth, zooplanktivorous fishes serve as forage for midsize piscivores, such as the Yellowtail, Mahogany and Schoolmaster Snappers, Red
Hind and Coney, as well as for large demersal and pelagic predators, such as Yellowfin
rouper, Cero Mackerels, Black and Horse-eye Jacks and Great Barracudas observed
uring ASEC surveys in this reef (Table 41). In contrast to shallow reef systems, and
consistent with observations at 30 m, herbivorous fishes comprised a minor taxonomic
component of the SW Wall Reef community at 40 m. Parrotfishes, doctorfishes and
damselfishes, which represented the main herbivorous assemblage, accounted for less
than 1 % of the total fish abundance within belt-transects.
Commercially important species for the aquarium fish trade market, such as the fairy
basslet (Gramma loreto), queen angelfish (Holacanthus ciliaris), rock beauty
(Holacanthus tricolor), blue chromis (Chromis cyanea) and yellowhead jawfish
(Opistognathus aurifrons) were present in the SW Wall reef at 40 m. Estimates of their
stock size, based on the total area of reef habitat between 34 – 40 m depths and the
species mean density (within belt-transects at 40 m), and/or their total abundance
(estimated from ASEC surveys) are presented in Table 40. Fairy basslets and blue and
sunshine chromis were observed in their full size range, indicative that they are
recruiting and spending their entire life cycle in this reef habitat. Queen angels and rock
beauties were observed in their full adult sizes, suggesting that the SW Wall reef may
function mostly as a foraging and/or reproductive (mating) habitat for these fish species.
Other fish targets of the aquarium trade, such as the Cherubfish or pigmy angel
(Centropyge argi) and the longsnout butterflyfish (Chaetodon aculeatus) were observed
in moderate abundance (0.9 – 1.2 Ind/m
2
).
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d
139
plankton food web, consistent with observations at 30 m. The top four most abundant
fishes within belt-transects (blue and sunshine chromis, masked goby and creole
wrasse) are known to feed mostly on zooplankton (Randall, 1967). The combined
zooplanktivorous assemblage represented at least 80 % of the total fish individuals
surveyed within belt-transects at 40 m. The fact that most of these fishes (except creole
wrasse) live close to the benthic reef habitat, suggests that demersal zooplankton plays
an important role in the trophic dynamics of this system.
s previously stated for the 30 m depth, zooplanktivorous fishes serve as forage for midsize piscivores, such as the Yellowtail, Mahogany and Schoolmaster Snappers, Red
Hind and Coney, as well as for large demersal and pelagic predators, such as Yellowfin
rouper, Cero Mackerels, Black and Horse-eye Jacks and Great Barracudas observed
uring ASEC surveys in this reef (Table 41). In contrast to shallow reef systems, and
consistent with observations at 30 m, herbivorous fishes comprised a minor taxonomic
component of the SW Wall Reef community at 40 m. Parrotfishes, doctorfishes and
damselfishes, which represented the main herbivorous assemblage, accounted for less
than 1 % of the total fish abundance within belt-transects.
Commercially important species for the aquarium fish trade market, such as the fairy
basslet (Gramma loreto), queen angelfish (Holacanthus ciliaris), rock beauty
(Holacanthus tricolor), blue chromis (Chromis cyanea) and yellowhead jawfish
(Opistognathus aurifrons) were present in the SW Wall reef at 40 m. Estimates of their
stock size, based on the total area of reef habitat between 34 – 40 m depths and the
species mean density (within belt-transects at 40 m), and/or their total abundance
(estimated from ASEC surveys) are presented in Table 40. Fairy basslets and blue and
sunshine chromis were observed in their full size range, indicative that they are
recruiting and spending their entire life cycle in this reef habitat. Queen angels and rock
beauties were observed in their full adult sizes, suggesting that the SW Wall reef may
function mostly as a foraging and/or reproductive (mating) habitat for these fish species.
Other fish targets of the aquarium trade, such as the Cherubfish or pigmy angel
(Centropyge argi) and the longsnout butterflyfish (Chaetodon aculeatus) were observed
in moderate abundance (0.9 – 1.2 Ind/m
2
).
A
g
d
139