SPECIES COLLECTED, FEEDING HABITS, AND TROPHIC LEVEL RELATIONSHIPS
The principal species collected were selected because they are commonly
eaten by the Marshallese; relatively abundant; have different feeding habits;
and
for
some,
represent
species
for
which
previous
available at Enewetak and Bikini for comparison.
radiological
data
was
It was not always possible,
however, to obtain an adequate number of the same species at every location we
sampled because of tides,
insufficient time, unavailability of a species, and
depletion of a species at inhabited atolls.
Various
reef
fish
were
collected.
Mullet
Neomyxus chaptalii are herbivorous, detrital
Convict surgeonfish Acanthurus
and
filamentous. algae that grow on reef rock or on the base of dead coral.
The
growing
on
herbivorous
Naso
lituratus,
sandy
and
browsers
garbage dump areas.
browsers.
All
browsers
and
fronds
unicornfish
herbivorous
crenilabis
feeders that ingest considerable
quantities of bottom sediment along with food.
triostegus are
Crenimugil
also
rocky
but
feeding
a
herbivore,
areas.
will
on
small
browses
Rabbitfish
occasionally
algal
feed
on
larger
Siganus
on
fleshy
seaweed
rostratus
items
are
found
in
Rudderfish Kyphosus cinerascens are strictly herbivorous
8
the above fish belong to the second trophic level.
of
Goatfish Mulloidichthys
other benthic
fauna
including small clams, crustaceans, other invertebrates, and small fish.
This
species
belongs
to
samoensis
the
consume
third
fossorial
trophic
and
level. ®
Threadfin
Polydactylus
sexfilis feed strictly on benthonic fauna and also belong to the third trophic
level.°
Parrotfish
Scarus
sordidus
are
common’
reef-dwelling,
omnivores feeding on live coral heads and occasional algae.
grazing
Parrotfish are in
the fourth trophic leve1.®
Four
crocea,
species
of
clams,
Tridacna
gigas,
and Hippopus hippopus were collected.
sessile,
filter-feeding
mollusks
that
live
Tridacna
squamosa,
These
large
the
lagoon
on
Tridacna
invertebrates are
bottom
and
coral
reefs.
Larger benthic,
midwater,
collected from the lagoons.
the
third
trophic
level
and
surface
carnivores
were
also
occasionally
Grouper Epinephelus sp. are benthic carnivores of
that
feed
on
small
fish
and
invertebrates. °
Jacks
Caranx melampygus and Elegatis bipinnulatus (rainbow runner) are fast~swimming
carnivores
that
feed
on
small
fish
occasionally eat swimming crustacea.
and
squid.
Elegatis
bipinnulatus
may
Snappers Aprion virescens (grey snapper)
and Lutjanus bohar (red snapper) are hovering midwater-to-surface carnivores.