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Some
interesting fishy facts...
• Some starfish can split their bodies in half then grow
new legs to make 2 whole starfish - ouch!
• It's the male seahorse
that has the babies - up to 400 at a time!
• Seahorses aren't very good swimmers so they hide in the seaweed
for protection.
• Fish have been around for 500 million years, fish were around
long before the dinosaurs roamed the earth
• There are about 25,000 different species of fish alive today.
• It is estimated that there may still be over 15,000 fish species
that have not yet been identified.
• What is the world's largest fish and The smallest?
The largest is the whale shark, which grows to more than 50
feet in length and may weigh several tons; second largest is
the basking shark, which may measure 35 to 40 feet long. The
smallest fish is the tiny goby, an inhabitant of fresh-to-brackish-water
lakes in Luzon, Philippines. It seldom is longer than a half
inch at adulthood, yet is so abundant it supports a fishery.
• Do Fish Sleep??
It all depends on what you mean by sleep. My dictionary says
that sleep is a period of rest in which the eyes are closed
and there is little or no thought or movement. That is, sleeping
means closing your eyes and resting. The first thing we notice
is that most fish don't have eyelids (except for sharks). Also,
while some deep ocean fish never stop moving a great many fishes
live nearly motionless lives and many do so on a regular diurnal/noctural
cycle, some active by day others by night.. So we can't generalize
and say that all fish sleep like we do. But most fish do rest.
Usually they just blank their minds and do what we might call
daydreaming. Some float in place, some wedge themselves into
a spot in the mud or the coral, some even build themselves
a nest. They will still be alert for danger, but they will
also be "sleeping."
• How is the age of a fish
determined?
Mainly by two methods: Growth "rings" on scales,
and/or ringlike structures found in otoliths (small bones of
the inner ear), are examined and counted. The rings correspond
to seasonal changes in the environment and can be compared
to the annual rings of tree trunks. A series of fine rings
are laid down in scales for each year of life in summer, the
rings grow faster and have relatively wide separations; in
winter, slower growth is indicated by narrow separations between
rings. Each pair of rings indicates one year. Because scale
rings are sometimes influenced by other factors, scientists
often use otoliths, whose ringlike structures also indicate
years of life.
•
Why do food fish sometimes have a strong odour?
For most species, truly fresh fish is almost odourless. Fish
begin to smell "fishy" when deterioration sets in,
often caused by incorrect storage practices that bring about
the release of oxidized fats and acids through bacterial and
enzymatic action.
Fishy defences
The ocean can be one of the most hostile places on earth
and creatures living there must develop specialised defences
in order to cope with the dangers that most threaten them.
Here are some of the important defensive adaptations.
• Sharp teeth and claws to ward off enemies.
• Hard shells provide soft bodies additional protection.
• Colour & camouflage disguise bodies in their
habitat making it difficult for predators to see them.
• Schooling provides individual fish added protection by
confusing predators with their sheer numbers.
• Poisons - there are many venomous fish, including the weaverfish
found in Irish waters. Anemones and jellyfish have stinging
cells to stun prey and protect themselves from predators.
• Spines on fish, such as sticklebacks and triggerfish, make
it difficult for predators to swallow them. Porcupine fish,
a.k.a. pufferfish, have spines, but are also able to inflate
their bodies making them look much larger and intimidating
to predators.
• Starfish and crabs can voluntarily drop off a limb as a
distraction for the predator, it will later regenerate that
limb.
• Cuttlefish and squid also distract by squirting ink at
predators.
• Electric eels can give electric shocks up to 500v
• In the deep sea, where there is no light, some species
are able to light up parts of their bodies as a form of defence.
Starfish
Sea stars (also known as starfish) are spiny, hard-skinned
animals that live on the rocky sea floor. Starfish are NOT
fish; they are echinoderms. Sea stars move very slowly along
the sea bed, using hundreds of tiny tube feet. There are
over 2,000 different species of sea stars worldwide.
Starfish are carnivores (meat-eaters). They eat clams, oysters,
coral, fish, and other animals. They push their stomach out
through their mouth (located on the underside of the sea
star) and digest the prey.
Most sea stars have five arms. Starfish do not have a brain;
they have a simple ring of nerve cells that moves information
around the body. Eyespots (primitive light sensors) are at
the tip of each arm. If a sea star's arm is cut off, it will
regenerate (regrow).
Sharks
Sharks are the most feared and perhaps the most misunderstood
creatures in the ocean. These magnificent creatures have
been on the planet for over 500 million years. They have
skeletons made of cartilage instead of bone, the same material
we have in our noses and ears. Most sharks swim constantly,
forcing water through their mouth and gill rakers, which
pull out the oxygen – this is how they breathe. Shark
skin feels like sandpaper. Eggs are laid in the form of a “mermaid’s
purse”, transparent cases that allow you to see the
baby shark inside. These take an average of 10 months to
hatch.
Mermaid’s Purse
Sharks have a very good sense of smell. They also have several
rows of teeth designed for ripping and tearing, their teeth
replace themselves every 10 days
or so. Sharks have unfairly earned a reputation as killing machines, eating
everything in sight, including humans. Only a few of the 250 species of shark
have ever been know to attack man, it is usually a case of mistaken identity – a
person on a surfboard looks very much like a seal from a shark’s point
of view.
For every 10 people attacked by sharks, over 10,000 sharks are killed by people.
They are usually hunted for their fins, as shark fin soup is a delicacy in
the Orient.
There are over 30 types of shark found in Irish Waters:
Porbeagle, Basking, Thresher, Shortfin Mako, Blue, Tope, Six-gilled, Bull Huss,
Dogfish, Smooth Hound and Spurdog. In deeper water you might find: Longnose,
Velvet Dogfish, Black Dogfish, Velvet Belly, Great Lanternshark, Iceland Catshark,
Mouse Catshark and Greenland Shark.
Seahorse
Seahorses are a type of small fish that have armored plates
all over their body (they don't have scales). There are
about 50 different species of seahorses around the world.
They live in seaweed beds in warm water and are very slow
swimmers. Seahorses can change their colour to camouflage
themselves in order to hide from enemies.
Seahorses have the head of a horse, the tail of a monkey
and it’s the male who has the babies!!
Reproduction: The female seahorse produces eggs, but they
are held inside the male's body until they hatch; he is pregnant
for about 40 to 50 days. The seahorse is the only animal
in which the father is pregnant.
Clownfish / “Nemo”
Clown fish (also called the Clown Anemonefish) are small
fish that live among anemone (fish-eating animals that look
like undersea flowers and have hundreds of poisonous tentacles).
Most of you will know the Clownfish from the Disney Pixar
film “Finding Nemo”.
This brightly-colored fish is orange with three white vertical
stripes; the rounded fins have black margins. The Clown fish
grows to be about 2 to 5 inches (5 to 13 cm) long.
The Clown fish lives on the sea floor amid anemone tentacles.
It inhabits the warm waters of the tropical Pacific Ocean,
the Red Sea, the Indian Ocean, and Australia's Great Barrier
Reef.
The Clownfish eat the anemone's leftover food. It also eats
dead anemone tentacles and plankton.
Bottlenose Dolphin
Bottlenose dolphins are small, toothed whales that have a
long, beaklike snout, a sickle-shaped dorsal fin, and sharp
teeth. Dolphins breathe air through a single blowhole.
They grow to be at most 12 feet (3.3 m) long. Dolphins
live in small groups of up to 12 ; these groups are called
pods. Bottlenose dolphins have a life span of about 35
- 40 years. Dolphins swim by moving their tail up and down.
Fish swim by moving their tail left and right.
Bottlenose dolphins are hunters who find their prey at the
surface of the water, eating mostly fish and squid
Bottlenose Dolphins are found in both temperate and tropical
oceans throughout the world.
Some sharks will prey upon dolphins. Dolphins are also often
trapped in fishing nets.
Dolphins are exceptionally playful creatures, often seen
leaping out of the water purely for fun. They are very friendly
and will interact with humans.
Fungi the Dingle Dolphin is a bottlenose Dolphin, Fungi can
be seen in the harbour of Dingle Bay. He has made Dingle
his home since 1984.
Sandtiger Shark / Carchariau taurus
These sharks are also know as Grey Nurse Sharks.
Sandtigers can grow up to a length of 10ft and weigh over
300lbs! They eat fish, mainly squid. There name comes from
their tendency towards shoreline habitats and they are often
seen trolling on the ocean floor near the shore line. They
are found in warm or temperate waters of the world such as
South Africa. Sandtigers are the only shark known to come
to the surface to gulp air. While menacing in appearance
this shark is generally considered to be harmless. The Sandtiger
Shark usually swims with its mouth open but
even when its mouth is closed the razor sharp teeth are still
clear to see.
Loggerhead Turtle / Caretta caretta
Molly our Loggerhead Turtle was found in August 2004 washed
up on a beach in Castlegregory, Co Kerry. The staff at the
aquarium have cared for her since then and she is now back
to full health apart from her damaged flippers which we think
occurred during a shark attack in the wild. Loggerhead Turtles
are an endangered species. They can weigh up to 350lb and
measure up to 3 feet in length. Loggerheads can live up to
about 60 years in captivity and they can live longer in the
wild. From our research we believe that Molly is in her 20s
or 30s. We have rehabilitated and released 6 loggerhead turtles
in the past 10 years: Spike, Omey, Blink, Peig, Saor and
Dylan.
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