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Arabian
Picassofish
(rhinecanthus
assasi)
 Length
up to 30cm, tan above and white below
with blue stripes between and below the
eyes. The Arabian Picassofish
inhabits
lagoons and seaward
reefs from 1m to 25m depth,
usually very territorial and wary, never
straying far from shelter.
Orbicular
Batfish
(Platax orbicularis)
The Orbicular
Batfish (Platax orbicularis)
is a popular
aquarium fish
endemic to tropical waters of
the
Indian and
Pacific Oceans.
Its body is almost
disc-shaped, and very thin; the tail,
about 20% of the body length, is
fan-shaped and taller than it is long.
Males can grow to up to 50cm in length,
though aquarium specimens are generally
much shorter. In the wild, the Orbicular
Batfish is found in brackish or marine
waters, usually around reefs, at depths
from 5 to 30 metres. Its range extends
from the
Red Sea and
East Africa in the east to
the
Tuamotu Islands in
French Polynesia in the west,
and from southern
Japan in the north to
northern
Australia and
New Caledonia. It has been
recorded off the coast of
Florida, though this may be
the result of dumping of aquarium
specimens.
Juvenile fish are
solitary or live in small groups, among
mangroves or other inner
sheltered lagoons. Adults are found in
more open waters and at greater depth.
(Bottlenose dolphins live in groups
)
called pods that
typically number about 15 dolphins, but
group size varies from solitary
bottlenose dolphins up to groups of over
100 or even occasionally over 1000
animals. Their diet consists mainly of
forage fish. Dolphin groups
often work as a team to harvest
schools of fish, but they
also hunt individually. Dolphins search
for prey primarily using
echolocation, which is
similar to sonar. They emit clicking
sounds and listen for the return echo to
determine the location and shape of
nearby items, including potential prey.
Bottlenose dolphins also use sound for
communication. Sounds used for
communication include squeaks and
whistles emitted from the blowhole and
sounds emitted through body language,
such as leaping from the water and
slapping their tails on the water.
There have been
numerous investigations of bottlenose
dolphin intelligence. Such testing has
included tests of mimicry, use of
artificial language, object
categorization and self-recognition.
This intelligence has driven
considerable interaction with humans.
Bottlenose dolphins are popular from
aquarium shows and television programs
such as
Flipper. They have also
been trained by militaries for tasks
such as locating sea mines or detecting
and marking enemy divers. In some areas
they cooperate with local fishermen by
driving fish towards the fishermen and
eating the fish that escape the
fishermen's nets. Some encounters with
humans are harmful to the dolphins:
people hunt bottlenose dolphins for
food, and dolphins are killed
inadvertently as a
bycatch of tuna fishing.
Cornetfish.
Ranging up to 200 centimetres
(6.6 ft) in length, cornetfishes are as
thin and elongate as many
eels, but are distinguished
by a very long snout, distinct
dorsal and
anal fins, and a forked
caudal fin whose center rays
form a lengthy filament. The
lateral line is
well-developed and extends onto the
caudal filament.
They generally live
in coastal waters or on
coral reefs, where they feed
on small fishes, crustaceans and other
invertebrates.
Cornetfish are of
minor interest for
fishing, and can be found in
local markets within their range.
The
dugong (Dugong dugon)
is a large
marine mammal which, together
with the
manatees, is one of four
living species of the order
Sirenia. It is the only
living representative of the
once-diverse family
Dugongidae; its closest
modern relative,
Steller's Sea Cow (Hydrodamalis
gigas), was hunted to
extinction in the 18th
century. It is also the only sirenian in
its range, which spans the waters of at
least 37 countries throughout the
Indo-Pacific. though the
majority of dugongs live in the northern
waters of
Australia between
Shark Bay and
Moreton Bay. In addition, the
dugong is the only strictly-marine
herbivorous mammal, as all species of
manatee utilize fresh water to some
degree.
Like all modern
sirenians, the dugong has a
fusiform body with no
dorsal fin or
hindlimbs, instead possessing
paddle-like
forelimbs used to maneuver
itself. It is easily distinguished from
the manatees by its fluked, dolphin-like
tail, but also possesses a unique skull
and teeth. The dugong is heavily
dependent on
seagrasses for subsistence
and is thus restricted to the
coastal habitats where they
grow, with the largest dugong
concentrations typically occurring in
wide, shallow, protected areas such as
bays,
mangrove
channels and the
lee sides of large
inshore
islands. Its
snout is sharply downturned,
an adaptation for
grazing and uprooting
benthic seagrasses.
The dugong has been
hunted for thousands of years, often for
its
meat and
oil, although dugong hunting
also has great cultural significance
throughout its range.[7]
The dugong's current distribution is
reduced and disjunct, and many
populations are close to extinction. The
IUCN lists the dugong as a
species vulnerable to extinction, while
the
Convention on International Trade in
Endangered Species limits or
bans the trade of derived products based
on the population involved. Despite
being legally protected in many
countries throughout their range, the
main causes of population decline remain
anthropogenic, and include hunting,
habitat degradation, and fishing-related
fatalities. With its long lifespan of 70
years or more, and slow rate of
reproduction, the dugong is especially
vulnerable to these types of
exploitation. In addition, dugongs are
threatened by storms, parasites, and
their natural predators,
sharks,
killer whales, and
crocodiles.
Emperor angelfish (Pomacanthus
imperator)
The emperor
angelfish, Pomacanthus imperator,
is a species of
marine angelfish. It is a
reef-associated fish, native
to the
Indian and
Pacific Oceans, from the
Red Sea to
Hawaii and the
Austral Islands. Juveniles
are dark blue with electric blue and
white rings; adults have yellow and blue
stripes, with black around the eyes. It
takes about four years for an emperor
angelfish to acquire its adult colouring.
They grow to 40 cm (15.75 in) in length.
The green
turtle is the quintessential
sea
turtle, possessing a
dorsoventrally-flattened body covered by
a large, teardrop-shaped
carapace and a pair of large,
paddle-like
flippers. It is
lightly-colored all around, while its
carapace's hues range from olive-brown
to black in Eastern Pacific green
turtles. Unlike other members of its
family such as the
hawksbill and
loggerhead turtles,
Chelonia mydas is mostly
herbivorous. The adults are
commonly found in shallow lagoons,
feeding mostly on various species of
seagrass.
Like other sea
turtles, green turtles are known to
migrate long distances between their
feeding grounds and the beaches they
hatched from. Many islands worldwide
have been called
Turtle Islands primarily for
the large amounts of green turtles that
nest on their beaches each year. Female
turtles dredge themselves onto beaches
and lay eggs in nests that they dig
during the night. After a period of
time, hatchlings emerge from the nests
and head for the water. Those that
survive grow to
maturity and live to a
maximum of eighty years.
However, the turtles'
populations are still in danger because
of several human practices. In some
countries, the turtles are still
hunted for their flesh and
their eggs are collected from nests and
eaten as a delicacy.
Pollution indirectly harms
the turtle populations both on the
population and the individual scale.
Many turtles die as a result of being
caught in fishermen's nets
and drowning. Finally,
habitat loss due to human
development is a major reason
for the loss of green turtle nesting
beaches.
Imbricate
turtle
The hawksbill
turtle (Eretmochelys imbricata)
is a
critically endangered
sea turtle belonging to the
family
Cheloniidae. It is the only
species in its
genus. The species has a
worldwide distribution, with
Atlantic and
Pacific
subspecies. Eretmochelys
imbricata imbricata is the Atlantic
subspecies, while Eretmochelys
imbricata bissa is found in the
Indo-Pacific region.
The hawksbill's
appearance is similar to that of other
marine turtles. It has a generally
flattened body shape, a protective
carapace, and its
flipper-like arms are adapted
for swimming in the open ocean. E.
imbricata is easily distinguished
from other sea turtles by its sharp,
curving
beak with prominent
tomium, and the
saw-like appearance of its
shell margins. While the turtle lives a
part of its life in the open ocean, it
is most often encountered in shallow
lagoons and
coral reefs where it feeds on
its chosen prey,
sea sponges. Some of the
sponges eaten by E. imbricata are
known to be highly toxic and lethal when
eaten by other organisms. In addition,
the sponges that hawksbills eat are
usually those with high
silica content, making the
turtles one of few animals capable of
eating siliceous organisms. They also
feed on other
invertebrates, such as
comb jellies and
jellyfish.
Manta ray
(manta Birostris)
The manta ray
(Manta birostris), is the
largest of the
rays, with the largest known
specimen having been more than 7.6 m
(about 25 ft) across, with a weight of
about 2,300 kg. It ranges throughout
tropical waters of the world,
typically around coral reefs.
Mantas have been
given a variety of common names,
including Atlantic manta,
Pacific manta, devilfish, and
just manta. Recent studies have
suggested that what is called manta ray
are at least two different species, one
smaller local and one much larger and
migratory
Mantas are filter
feeders: they feed on
plankton, fish larvae and the
like, passively filtered from the water
passing through their gills as they
swim. Small prey organisms are caught on
flat horizontal plates of russet-colored
spongy tissue spanning spaces between
the manta's gill bars.
Mantas frequent
reef-side
cleaning stations where small
fish such as
wrasses and
angelfish swim in the manta's
gills and over its skin to feed, in the
process cleaning it of parasites and
removing dead skin.
The predators of the
Manta ray are mainly large sharks,
however in some circumstances
orcas have also been observed
preying on them.
Mantas are extremely
curious around humans, and are fond of
swimming with scuba divers. Although
they may approach humans, if touched,
their mucus membrane is removed, causing
lesions and infections on their skin.
They often surface to investigate boats
without engines running. They have the
largest brain-to-body ratio of the
sharks and rays.
Mantas are known to
breach the water into the
air.
Napoleonfish
(Cheilinus undulatus)
The largest known
member of the family with a very
distinctive tall and stubby structure .
large mouth with thick protractile lips
that allow prey literally to be sucked
up. In adults, the head is marked by a
pronounced bump on the forehead.
Greenish gray with irregular greenish
yellow stripes along the sides, shifting
to orange on the head. Can grow as long
as 2 meters and weigh more than 180
kilograms.
(An
octopus has eight arms)
, which trail
behind it as it swims. Most octopuses
have no internal or external skeleton,
allowing them to squeeze through tight
places. An octopus has a hard beak, with
its mouth at the center point of the
arms. Octopuses are highly intelligent,
probably the most intelligent of all
invertebrates. For defense against
predators, they hide, flee quickly,
expel ink, or use color-changing
camouflage.
Octopuses are highly
intelligent, likely more so
than any other order of
invertebrates. The exact
extent of their intelligence and
learning capability is much debated
among biologists,[7][8][9][10]
but maze and
problem-solving experiments
have shown that they do have both
short- and
long-term memory. Their short
lifespans limit the amount they can
ultimately learn. There has been much
speculation to the effect that almost
all octopus behaviors are independently
learned rather than instinct-based,
although this remains largely unproven.
They learn almost no behaviors from
their parents, with whom young octopuses
have very little contact.
When octopuses
reproduce, males use a specialized arm
called a
hectocotylus to insert
spermatophores (packets of
sperm) into the female's mantle cavity.
The hectocotylus in benthic octopuses is
usually the third right arm. Males die
within a few months of mating. In some
species, the female octopus can keep the
sperm alive inside her for weeks until
her eggs are mature. After they have
been fertilized, the female lays about
200,000 eggs (this figure dramatically
varies between families, genera, species
and also individuals). The female hangs
these eggs in strings from the ceiling
of her lair, or individually attaches
them to the
substrate depending on the
species. The female cares for the eggs,
guarding them against predators, and
gently blowing currents of water over
them so that they get enough oxygen. The
female does not eat during the roughly
one-month period spent taking care of
the unhatched eggs. At around the time
the eggs hatch, the mother dies and the
young larval octopuses spend a period of
time drifting in clouds of
plankton, where they feed on
copepods, larval
crabs and larval
starfish until they are ready
to sink down to the bottom of the ocean,
where the cycle repeats itself. In some
deeper dwelling species, the young do
not go through this period. This is a
dangerous time for the larval octopuses;
as they become part of the plankton
cloud they are vulnerable to many
plankton eaters.
Reef Squid
(Teuthida)
The
Reef Squid is found throughout the
Caribbean Sea as well as off
the coast of Florida, commonly in small
schools of 4-30 in the
shallows associated with
reefs. The
habitat of the Reef Squid
changes according to the squid's stage
of life and size. New hatchlings tend to
reside close to the shore in areas from
0.2-1 meters below the surface on or
under
vegetation. Young small squid
typically congregate in shallow
turtle grass near islands and
remain several centimeters to two meters
from the surface to avoid bird
predators. Adults venture out into open
water and can be found in depths up to
100 m. When mating, adults are found
near coral reefs in depths of 1.5-8 m.
Remoras
or suckerfish
Remoras
or suckerfish are elongated brown
fish in order
Perciformes and family
Echeneidae. They grow to 30–90
centimetres long (1–3 ft), and their
distinctive first
dorsal fin takes the form of
a modified oval
sucker-like organ with
slat-like structures that open and close
to create suction and take a firm hold
against the skin of larger marine
animals. By sliding backward, the remora
can increase the suction, or it can
release itself by swimming forward.
Remoras sometimes attach to small boats.
They swim well on their own, with a
sinuous motion.
Remoras are primarily
tropical open-ocean dwellers,
occasionally found in
temperate or coastal waters
if they have attached to large fish that
have wandered into these areas. The
sucking disc begins to show when the
young fish are about 1 centimetre long.
When the remora reaches about 3
centimetres, the disc is fully formed
and the remora is then able to hitch a
ride. The remora's lower jaw projects
beyond the upper, and there is no
swim bladder.
Some remoras
associate primarily with specific host
species. Remoras are commonly found
attached to sharks,
manta rays, whales, turtles,
and
dugong. Smaller remoras also
fasten onto fish like tuna and
swordfish, and some small
remoras travel in the mouths or gills of
large manta rays,
ocean sunfish, swordfish, and
sailfish.
The relationship
between remoras and their hosts is most
often taken to be one of
commensalisms, specifically
phoresy. The host they attach
to for transport gains nothing from the
relationship, but also loses little. The
remora benefits by using the host as
transport and protection and also feeds
on materials dropped by the host. There
is controversy whether a remora's diet
is primarily leftover fragments, or the
feces of the host. In some species
consumption of host feces is strongly
indicated in gut dissections. For other
species, such as those found in a host's
mouth, scavenging of leftovers is more
likely. For some remora and host
pairings the relationship is closer to
mutualism, with the remora
cleaning bacteria and other parasites
from the host.
Spot-fin porcupinefish
(Diodon
hystrix)
Diodon hystrix
may be up to 91cm long and weigh as much
as 2.8kg. It is coloured tan with dark
spots above and pale below, and has many
long, moveable spines. It is largely
nocturnal.
Juveniles are
pelagic up to the time that
they are about 20cm in length. Adults
favour
lagoons and seaward
reefs, sheltering under
ledges or in caves during the day.
Although classified as
benthic, they may sometimes
be found hovering high in the water.
Oval, rounded body
; short, snupped
snout; small mouth. Dorsal fin extends
along much of the dorsum and presents a
slight saddle formation that separates
the spinous portion from the portion
with the soft rayc; 2 lopes on the
caudal fin. Background coloring ranges
from orange to brownish orange. With 2
white vertical stripes. Young specimens
may have a third stripe on the stalk of
the tail fin. Generally lives in
symbiosis with anemonefish of the genus.
Can grow 15cm long.
Whale
shark (Rhincodon
typus)
The whale shark, Rhincodon typus,
is a slow moving
filter feeding
shark that is the largest
living
fish
species. It can grow up to
12.2 m (40 ft) in length and can weigh
up to 13.6 tonnes (15 short tons). This
distinctively-marked shark is the only
member of its
genus Rhincodon and
its
family, Rhincodontidae
(called Rhinodontes before 1984), which
is grouped into the subclass
Elasmobranchii in the class
Chondrichthyes. The shark is
found in
tropical and warm oceans and
lives in the open sea and can live for
about 70 years. The species is believed
to have originated about 60 million
years ago. Although whale sharks have
very large mouths, they feed mainly,
though not exclusively, on
plankton, microscopic plants
and animals. As a
filter feeder it has a
capacious mouth which can be up to 1.5 metres
(4.9 ft) wide and can contain between
300 and 350 rows of tiny teeth. It has
five large pairs of
gills. Two small eyes are
located towards the front of the shark's
wide, flat head. The body is mostly grey
with a white belly; three prominent
ridges run along each side of the animal
and the skin is marked with a
"checkerboard" of pale yellow spots and
stripes. These spots are unique to each
whale shark and because of this they can
be used to identify each animal and
hence make an accurate population count.
Its skin can be up to 10 centimetres
(3.9 in)
thick. The shark has a pair each of
dorsal fins and
pectoral fins. A juvenile
whale shark's tail has a larger upper
fin than lower fin while the adult tail
becomes semi-lunate (or
crescent-shaped). The whale shark's
spiracles are just behind the
eyes.
This
species, despite its enormous size, does
not pose any significant danger to
humans. It is a frequently cited example
when educating the public about the
popular misconceptions of all sharks as
"man-eaters". They are actually quite
gentle and can be playful with divers.
Divers and snorkelers can swim with this
giant fish without any risk apart from
unintentionally being struck by the
shark's large tail fin.
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