The Best Experience on the Great Barrier Reef - LADY MUSGRAVE REEF FACTS 07 4151 5225 - Lady ...
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
LADY MUSGRAVE
REEF FACTS
The Best Experience on the
Great Barrier Reef
07 4151 5225
ladymusgraveexperience.com.au 
2300KMS OF QUEENSLAND REEF
COOKTOWN
8000 YEARS OLD
CAIRNS
TOWNSVILLE
MACKAY
Great Barrier Reef
Lady Musgrave
Island
ROCKHAMPTON
AU S TR ALI A
BUNDABERG
SUNSHINE COAST
BRISBANE
GOLD COAST
large reef areas exposed. It is during
these times that the wind eroded
large gullies and ridges amongst the
coral. When the polar caps melted
up of over 2,700 individual reefs with and sea levels rose, what was
ORIGIN OF almost as many islands and cays. once dry limestone bedrock once
THE GREAT The first reef systems began to grow
again supported coral growth. This
process of sea level change has
BARRIER REEF in this area some 2 million years
ago when Northern Australia drifted
occurred many times in the last 2
million years since the reef formed.
The Great Barrier Reef is one into the tropics. Due to tides and
of the world’s most complex and currents many different organisms Due to this continual growth of new
biologically diverse ecosystems. drifted down from the surrounding coral over the old skeleton as the
The reef stretches for 2,300 areas of Malaysia and Indonesia sea level rose and fell, the Great
kilometres along most of the where they were able to establish Barrier Reef today in most places is
Queensland coast, starting at Cape and grow in this new environment. a maximum of 300 metres thick. The
York in the north to just north of Since this time several ice ages present day Great Barrier Reef is
Bundaberg in the south. The reef have occurred resulting in dramatic around 8000 years old with much of
however, as the name suggests is sea level changes. During each ice this growth taking place in a period
not one continual barrier but is made age, sea levels subsided leaving of relatively stable sea levels.
REEFSCAPES and rainwater but maintain their
basic shape. After rising sea levels
Lady Musgrave’s story began submerge them again, new coral
2 million years ago when coral reefs grows over the ancient structure.
first began to form in this area.
Sea level reached its lowest (about
SEA LEVEL STABILISED Following their formation, reefs have
120m below the present level) in the
6000 YEARS AGO been flooded and stranded as sea
last ice age some 18,000 years ago.
levels have risen and fallen. When
At that time land reached out to the
reefs are exposed as limestone hills
edge of the continental shelf. The
at times of very low sea level, they
polar icecaps began to melt, and
are eroded by wind
for 10,000 years the sea level rose.
Coral grew on the mounds of the old
reefs as they were submerged, but
could not keep up with the rising
sea. About 6,000 years ago, the
sea level stabilised, and reefs grew
closer to the surface. Some have
now reached sea level, while others
are still well below it.
SOUTHERN
GREAT
BARRIER REEF
DISCOVERY years. (In 1983 a large bulk carrier,
the TNT Alltrans grounded on Lady
At the southern end of The Great
Barrier Reef, close to the Tropic of
In 1770, Captain James Cook Musgrave Reef, but was refloated). Capricorn, lies a string of islands
travelled up the Queensland coast Capricornia’s peace was shattered in and reefs known as “Capricornia”
close to the mainland, out of sight of the late 19th Century with the arrival the Capricorn and Bunker Group.
the islands of Capricornia. Flinders of miners seeking phosphate rock Capricornia’s 22 reefs, 13 of them
in 1802 may have seen Masthead or guano. They began on Lady Elliot with islands, are about 80km
Island but the first definite sighting Island in 1863 and left a devastated from the mainland, in the shallow
of the Capricornia cays was by landscape stripped of trees and seas above the continental
Captain Bunker in 1803. The topsoil. Grazing goats aggravated shelf. Capricornia is an important
southernmost cay on the reef, Lady the damage and only in the last conservation area and is part of
Elliott Island was named after Lady 20 years has the island begun to the World Heritage Site declared
Elliot which sailed past in 1816. The recover. Fairfax and Lady Musgrave over the Great Barrier Reef.
island’s position was fixed three Islands were mined at the end of
Eighteen thousand years ago, the
years later by Phillip Parker King, the 19th Century, and on both
reefs of Capricornia were limestone
on the first of his 3 voyages to the these islands, goats also caused
hills on a coastal landscape.
southern reef. On his second voyage extensive damage.
Aboriginal family groups painted
in 1820, King named the island and
Lady Musgrave Island was the site in the caves and harvested rich
in 1821 he observed several other
of Capricornia’s second tourist food supplies from the coastal
Capricornia Islands. Masthead Island
resort, established in 1939, but plains and fringing reefs. Then,
was named in 1839 by Wickham
this soon closed due to financial generation after generation, the
and Stokes in the Beagle, then in
troubles. (The first tourist resort was tribes traditional hunting grounds
1843 Captain Blackwood in H.M.S.
established in 1932 on Heron Island, were flooded by a slowly rising
Fly, accompanied the Bramble and
utilising the old turtle soup cannery). sea. The cays which developed in
surveyed all the islands and reefs.
Canneries were established on both Capricornia were a long journey
The party visited North West Island
Heron and North West Islands in the across often rough water and there
and named Wreck Island (after the
early 1900’s. Harvesting ceased by is no evidence that they were
America which was wrecked there
1930 due to over exploitation and visited by Aboriginals.
in 1831), Heron Island (named after
20 years later turtles were
the graceful egrets) and One Tree
protected. Half of Lady Musgrave
Island. Jukes also wrote about Lady
Island was declared a national park
Musgrave, calling it “The First Bunker
in 1938 with the remainder declared
Island”. Lady Musgrave Island was
in 1967. CAPRICORN
named after Jeannie, the American
born wife of a Queensland Governor,
KEPPEL IS.
GROUP
Sir Anthony Musgrave.
YEPPOON WILSON IS.
NORTHWEST IS.
Later as ports of central and
LADY MUSGRAVE HERON IS.
northern Queensland became MASTHEAD
established, shipping in the vicinity ISLAND WAS CAMP IS. FITZROY REEF
of Capricornia increased. In 1866 a NAMED AFTER LLEWELLYN REEF BOULT REEF
temporary lighthouse was erected
on Lady Elliott Island and a more
THE QUEENSLAND GLADSTONE
FAIRFAX IS.
LADY MUSGRAVE
permanent structure was built in GOVERNOR
1873. North reef lighthouse followed
in 1878. A lighthouse was placed
SIR ANTHONY BUNKER
on Lady Musgrave Island in 1974. In
MUSGRAVE’S WIFE GROUP
spite of these beacons, there have
been numerous shipwrecks over the
AUSTRALIA
BUNDABERG
LADY MUSGRAVE
ISLAND IS A
14 HECTARE
CORAL CAY
THE SHELTERED
LAGOON IS UP TO
LADY MUSGRAVE 8 METRES DEEP
ISLAND AND REEF
Lady Musgrave Island is the southernmost island in the Much of the island has been formed from coral shingle,
Bunker Group. The island is a 14-hectare coral cay with a and its shallow soils, along with strong winds, have
1192 ha surrounding reef, occupied by a large sheltered influenced the vegetation.
lagoon. Cays in Capricornia such as Lady Musgrave are
The tree canopy is low compared to sandy cays further
low, flat islands which have never been connected to the
north, rising from 6 – 8 metres on the southern side to a
mainland but have formed from the reef which surrounds
maximum of about 15 metres. The open vegetation of the
them. They develop as fragments of coral, algae and
southern eastern side of the island gives way to rambling
other reef inhabitants are deposited on one part of the
stands of Pisonia and sandpiper fig in the centre. The
reef, (usually the leeside) by waves and storms. This
Pisonia forest gradually increase in height and density
process has resulted in the formation of Lady Musgrave
towards the sheltered north western side.
Island. The surrounding beaches are mostly sandy.
Conglomerate and beach rock outcrops which can be The island tree Pisonia (Pisonia grandis) is well adapted to
seen on the island, have been formed by chemical island life, and often grows in dense forests which allows
processes which cement the coral shingle and sand. little light to penetrate the forest floor, thus excluding
most other plants. Pisonias flourish in the calcium rich
The platform reef of Lady Musgrave has distinct natural
cay soils and in dry times survive by shedding leaves.
zones and includes a deep lagoon. The windward reef
Branches blown down in storms sprout new leaves
slope is steep, with a “spur and groove” structure. On
and roots. The sticky seeds are dispersed by seabirds,
the spurs are beautiful branching staghorn corals whilst
especially the black noddies that nest in the Pisonias.
the grooves that are scoured by tides and currents,
are relatively bare. The reef crest, a rocky rim, is the The beach on the lee side of Lady Musgrave is backed
highest point on the reef and is covered with cemented by stands of the graceful coastal sheoak and on the
encrusting algae. windward side by pandanus trees. On the beach,
creepers, herbs and grasses, such as the green,
The outer edge of the reef flat boasts many coral
pincushion like beach carrot are abundant.
varieties, whilst sand dominates the bottom, inside the
lagoon. The sheltered lagoon is up to 8 metres deep Native animals living on the island arrived by flying,
with intermittent patch reefs. The lagoon provides an drifting or swimming, or by clinging to floating plants,
excellent anchorage and is connected to the sea through flotsam or other animals. To be permanent residents,
a steep sided channel. The lee reef slope is gentle and they must be able to survive on the island through
supports an interesting variety of corals, which are drought and cyclone. Insects, spiders and other
not exposed to the strong seas of the windward slope. arthropods are common on
Large coral heads or bommies (abbreviation of aboriginal Lady Musgrave, but there are no mammals or reptiles
word “bombora”) are home to countless fish and other (except visiting turtles) and only a few resident land birds.
marine life. Many more land birds visit the island to feed, roost or
breed, but do not stay permanently.
THE GREAT 8
WHAT WILL The Great 8 is a variety of special animals only seen here in their
I SEE WHEN natural habitat. Each iconic animal is selected because of its
connection to the Great Barrier Reef, importance to the marine
SNORKELLING AT eco-system and you guessed it, location.
LADY MUSGRAVE
WHALES
When snorkelling around the large
The Humpback whales arrive in the
coral bommies adjacent to the boat,
Southern Great Barrier Reef as part of
you will get the most out of your
their winter migration to calve, mate and
snorkelling experience by following
socialise. Best seen during June
the reef edge and around the
to October.
bommies, where you will encounter
the greatest diversity of life. While
TURTLES
approaching the reef edge and
Turtle nesting from October to February and
coral bommies you will see large
hatching from January to March of each
sea cucumbers laying on the lagoon
year is an amazing experience that you
floors. A part of the starfish family,
will remember for many years to come.
sea cucumbers are known as the
vacuum cleaners of the reef because
of the way they clean the sand of
SHARKS
fish waste and bacteria. The lagoon When snorkelling around the large coral
has large formations of staghorn bommies adjacent to the boat you’ll see
coral. These are normally very many species of sharks.
brightly coloured, however some
have colouration only on the tips. The CLOWNFISH
blue blanket coral is commonly found If you have seen the movie Finding
growing up the reef edges. Mushroom Nemo, you would already know
corals are the only corals that will just how cute and illusive this little guy
move with the tide or current, looking can be.
like a grooved “frisbee”. When the
feeding tentacles are extended they GIANT CLAMS
resemble small anemones. If you have never been to the Great Barrier
Reef, these animals will really blow you
Close to the boat on the reef edge
away. Growing up to 1.5 metres in length
there are some giant clams. The
and weighing up to 200kg and like a
clams’ hard shell is open when in
hand-print, it has a mantle pattern and
feeding mode and will gently close
colour unique to itself.
as its primitive eye detects changes
in light. Another type of clam can
also be seen amongst the coral,
POTATO COD
the burrowing clam – buries itself This giant grey-brown cod can grow
in the coral. up-to two metres in length and
weigh in at 100kgs. Many divers have
In strategic positions around the close encounters with the fish due
lagoon are “cleaning stations”, to its friendly nature and inquisitive
managed by the cleaner wrasse, personality.
a small blue and white fish. The
cleaner wrasse waits for the other RAYS
fish to pass through this area,
It is well documented that Manta Rays
when they do they will pause while
will actually seek out and play around
the cleaner wrasse passes over their
Scuba Divers and Snorkellers making
body eating ectoparasites and mucus
diving or snorkelling with Manta Rays a
off the fish. The cleaner wrasse will
truly unique experience.
actually enter the mouth and gill
cavities of some of the larger fish to
MAORI WRASSE
complete a more thorough job.
This distinctive fish has thick fleshy
lips and a bump that juts out from
its forehead. What it lacks in looks it
makes up in personality.
Fig 1: Anatomy of a coral
polyp showing the
location of zooxanthellae
(Image source Encyclopedia
Britannica)
THE FORMATION AND
GROWTH OF CORAL REEFS
The Great Barrier Reef is the largest rich, sunlit areas are able to deposit
structure made by living animals, their limestone skeletons 2 – 3 times
however, the builders are amongst faster than those that don’t undergo
the smallest and simplest of photosynthesis. It is this limestone
organisms. These animals are coral skeleton that gives the coral
polyps and each one resembles an colonies their rigid framework.
upside-down jellyfish. The polyps
When corals actively feed as
consist of a simple cup shape body
opposed to obtaining their food
with an opening surrounded by a
through photosynthesis, the polyp
ring of tentacles at the top.
extends it’s tentacles into the water
There are a number of different column. Each tentacle is armed with
varieties of coral however only one stinging cells called nematocysts.
particular type, the scleractinian or Certain groups of the stinging cells their spawning. This process takes
hard coral, is responsible for building ensnare the prey while others will place in Spring just after sunset
coral blocks or bommies. paralyse it. The struggling prey whilst the moon is full. The tides
activates other cells which aid in need to be at their weakest so drift
Coral polyps have a special
passing the prey to the mouth. The is minimal. This spectacular event
symbiotic relationship with a tiny
was only discovered in 1982 and
plant or algae called zooxanthellae. polyp will catch minute zooplankton
overcomes the problem of uniting
These single-celled algae are (a combination of microscopic
sperm and eggs from sparsely
usually only found in corals growing organisms and larvae).
separated colonies.
30 degrees north and south of
Corals show great inventiveness in
the Equator, where the water This form of reproduction is sexual
their reproductive abilities and it’s
temperatures are warmer. It is as opposed to asexual in which the
quite possible that many modes
this algae that gives the coral its colonies “bud” off new polyps.
of reproduction are yet to be
different colours.
discovered. The most common form A living coral reef would not be
This microscopic algae lives inside of reproduction – coral spawning, complete without the encrusting
the coral’s tissue and it uses the is also the mechanism that allows coralline algae which cements the
sun’s energy to photosynthesize, for greatest dispersal and genetic colonies together. Beneath ledges
a process in which organic carbon is mixing. This annual occurrence is and in crevices lay countless animals
produced. Between 95 – 98% of this one of the reefs most dramatic such as bryozoans, soft corals and
carbon leaks from the algae and is events. The difficulties involved in sponges. This unique environment
a valuable food source for the coral external fertilisation of corals have supports an amazing array of fish
polyp. Additionally, those corals in led many colonies to synchronise and other vertebrates.
CORAL BIOLOGY
3
CORAL IS MADE UP OF Over 600 different species of corals The third group of corals are the
1
are present on the Great Barrier boulder. These include brain and
CALCIUM CARBONATE
Reef. Due to the numerous species honeycomb corals (all of which
of hard corals, they are normally resemble their name) along with
classified into three main groups the porites coral. On average these
depending on their growth form. The corals usually only grow 3 – 4mm per
first group are perhaps the most year. It is these colonies however
prolific on the reef and certainly that can withstand the force of
the most opportunistic. They are storms and cyclones.
REEF TYPE branching corals otherwise known
Hard corals all consist of a calcium
as staghorn coral. These colonies
The three main types of reefs carbonate or limestone skeleton.
resemble the antlers of a stag deer,
present in the Great Barrier Reef This skeleton is relatively porous
hence their name. In ideal conditions
region are ribbon, fringing and and care must be taken when
these corals can grow up to 20
platform reefs. In the Capricornia approaching the colonies. Branches
centimetres per year. These colonies
region platform reefs are common. of staghorn coral are very easily
are however the most susceptible
Platform reefs are known for their broken and soft tissue can be
to strong winds and storms with
2
variety of shape and form. Some damaged if the boulder corals
large branches breaking easily. This
may be immense – stretching are lent on.
opportunistic family of corals tend to
over 22 kilometres across. In all
be the first to colonise barren areas
cases their geological history can
with lagoons and on reef flats.
be varied. Reefs can be classified
according to their age and coral The second group – the plate OVER 600
corals, form large ‘table top’ or
growth rate. Juvenile reefs are SPECIES OF HARD
those whose coral colonies are still plate-like structures on the sides
growing towards the surface. Mature of coral platforms. Many of the AND SOFT CORAL
reefs have well developed reef flats plate corals belong to the same
and sheltered lagoons. Senile reefs family as the branching corals but CORAL SPECIES:
occur in areas in which the lagoon have dramatically different growth
is largely filled in with sand and forms. Plate corals grow about 8 – 10 STAGHORN CORALS
cays may develop. Northern areas centimetres per year and provide PLATE CORALS
excellent shelter for fish such as the
tend to have ribbon reefs with few BOULDER CORALS
lagoonal areas. coral cod and butterfly cod.
FISH OF THE GREAT
BARRIER REEF
The Great Barrier Reef supports over 1500 species of fish ranging from
OVER 1500 SPECIES
large predatory varieties through to delicate coral fish. A majority of the fish
species are found within Lady Musgrave lagoon. Although identification may OF FISH ARE FOUND
be seen daunting at first, it is possible to become familiar with the majority AT THE GREAT
of reef fishes. The bulk of the fish species found on the coral reef belong to
relatively few families. Below are 4 of the most common families together with
BARRIER REEF
identifiable behavioural themes.
DAMSELFISH BUTTERFLYFISH
These fish are perhaps the most prolific of all reef Perhaps the best known of all the reef fish, the
fish. They feed solely on plankton and form large butterflyfish are epitomised by their graceful
swarms in the main snorkelling area. Included in this movements and intricate colour patterns. Most
family are the black and white striped Sargent Majors species feed partly or exclusively on coral tissue.
and the brilliant coloured Blue Chromis. Territoriality is fierce and these fish are often sighted
in pairs which are thought to be lifetime bonds.
PARROTFISH CLOWNFISH
Being a close relative of the wrasse, the parrotfish Clownfish shelter in the tentacles of anemones,
can also display amazing colouration. It is only the immune from their hosts stinging cells. The fish and
males however that are usually a bright blue or green their eggs gain protection from predators, which
colour. These fish are well known for the harems they would be stung if they brushed against the anemone.
form. Groups of 8-9 females with one male leader Clownfish are never found without their hosts, but the
can often be observed grazing on algae and coral. anemones do not rely on the fish and can
The females are normally a drab grey or brown colour live well without them.
and possess the ability to change sex to a male. This
change normally occurs if the dominant male in the
group dies. The Parrotfish are so important to the
reef because they keep the delicate balance between
algae and coral in check. They’re vital in clearing algae
away so that new baby corals have a clean slate to
settle and grow on.
Other fish commonly encountered are angelfish,
cardinalfish, gropers, surgeonfish and biennies.
Fish are an integral part of any reef It is possible to hear the parrotfish unusual methods of reproduction is
system with each species having an crunching on the coral whilst you are found in cardinalfish. In this instance
important role to play in the entire snorkelling. the male will incubate the eggs
ecosystem. For example, certain within his mouth.
Behavioural feeding methods vary
types of fish may harvest a specific
for some of the larger carnivorous Limited information is available on
type of algae. If these fish were
fish species. Some fish are ambush the life span of most reef fish. It is
removed and the algae no longer
predators that will sit and wait for possible that sharks may live to at
had any predators, then the growth
their prey to swim past. Lightning least 20 – 30 years while large fish
of the algae would accelerate
speed is displayed as the ambush such as snapper and gropers can
dramatically, smothering coral
predators ensnare their prey. Other live to around 25 years. Although
colonies close by.
carnivorous varieties such as the certainty surrounds the longevity of
There are many different feeding reef sharks tend to be open water smaller fish it is thought that species
modes for reef fish and most are hunters with specialised teeth to such as Damselfish and Angelfish
specialised to particular species. seize and tear the flesh of their prey. can live up to 10 years or more.
Most of the smaller fish which make
Reproductive methods among reef In the intermediate snorkelling area,
up the bulk of the daytime reef
fish tend to be quite unusual. The you will see sweetlip, coral trout,
population are planktivores
vast majority of reef fish are big egg silver trevally, fusiliers, humbugs,
or herbivores.
layers, and this usually occurs in one surgeonfish, wrasse, parrotfish
A majority of damselfish hang high of two elaborate ways. and countless other varieties. Blue
in the water column and pick off Linckia starfish, sea urchins and
Frequently spawning occurs at dusk
pieces of algae as they float past. Beche-de-mer are also plentiful.
and may not only involve the male
Other varieties of damselfish will Beche-de-mer aka sea cucumbers
and the female but also a group
vigorously defend a patch of “farm” are the dark looking sea slugs you
of participating fish. The process
of algae amongst the coral. This so will see on the sandy white bottom
begins as both participants swim
called “land ownership” comes with of the lagoon. These animals should
towards the surface. Spawning
the added advantage of a protected not be handled since they eject
culminates as eggs and sperm are
egg laying site. sticky white threads in defence.
released at precisely the same time
The threads aren’t too harmful but
Parrotfish, surgeonfish and the fish turns and heads back to
are hard to remove and can leave
rabbitfish all feed on the algae that the bottom. Parrotfish, wrasse
an irritating rash for a few days. As
grows on rocky surfaces and coral. and butterflyfish all exhibit this kind
they feed they also break down the
It is impossible for these fish whilst of spawning.
course sand on the lagoon floor into
they are scraping the algae to
Other species such as gobies, a fine sand.
separate it from the coral skeleton or
triggerfish and damselfish will lay
rock. Therefore the parrotfish have
their eggs on the bottom. Preceding
evolved a beak like structure for a
the spawning, the area of coral is
jaw which they use to bite off pieces
cleaned of any algae and detritus.
of coral. Located at the back of their
After the eggs have been fertilised
throat are special teeth that grind
one or both parents care for the
the coral skeleton to a fine powder
nest until hatching. One of the more
which is expelled with the faeces.
TURTLES
Turtle nesting season occurs along the entire length As with all reptiles, the hatching sex is determined by the
of the Queensland coast on suitable beaches during nest temperature. This is known as the pivotal temp and
the months of November to February. For islands of the varies from species to species. Warmer nests produce
Great Barrier Reef the season is extended with laying females while cooler nests produce males. It can be
commencing in mid-October and continuing through to predicted that coastal rookeries with darker sand absorb
the end of March. the suns heat and produce females while Great Barrier
Reef islands with their white sand reflect the sun and
We are fortunate enough to have 6 of the 7 species
produce more males.
of sea turtles nesting in Queensland waters. At Lady
Musgrave it is mainly the Green turtle that frequents the Turtle hatchlings emerge 7 – 12 weeks later and make
island although Loggerhead turtles may also be seen. their way down to the sea. Hatchlings will navigate to the
The Green Turtle is the second largest of the 7-species lightest part of the horizon and any artificial lights from
growing to just over a metre in carapace length. the beach, will confuse them in their direction of travel.
Sea turtles make distinctive tracks as they haul Mystery surrounds the first 10 years of a turtle’s life and
themselves ashore and it’s possible to distinguish each is commonly known as the “lost years”. It is thought
species by their tracks. The Green Turtle moves along however that the hatchlings get caught up in the great
with both flippers together in a rowing motion whereas ocean currents and float around feeding on surface
the Loggerhead will move its front flippers alternatively, organisms. Once they reach the age between 7 – 12 years
first left then right and so on. It is only ever female turtles they are able to actively swim against the currents and
that will come ashore, males will never make their way they return to reefal areas to feed. It is at this stage they
onto the beach. are around the size of a dinner plate.
During mating season, it is possible for a female to mate Studies indicate that turtles are around 30 – 35 years
with several different males over a period of time. She will of age when they reach sexual maturity. It is at this time
store this sperm and use it only when required. that they return to their natal beach to lay for the first
time. Green Turtles are herbivorous opting to graze on
Once the female is ready to lay her eggs, she’ll make her
algae and seagrass while Loggerheads are carnivorous
way up into the sand dunes above high tide mark. If the
feeding on crustaceans, jellyfish and small fish.
eggs were laid below this level, they would spoil as salt
water enters the nest. The hole that she digs with her Green Turtles can weigh between 110 – 190kg while
hind flippers is usually 70 – 90cm deep. She will continue Loggerheads can weigh between 70 – 170kg. The
to lay between 80 – 200 eggs the size of ping pong balls. Capricorn Bunker Group of islands support one of the few
It is critical that the female is not disturbed in the time remaining large concentrations of nesting green turtles
she leaves the water to the time she begins laying. If the in the world.
female is disturbed she may retreat back to the water
often spilling her eggs on the way or in the water. Each
female can come ashore 5 or 6 times during the nesting
season and will usually return in 2 – 3 years time.BIRDS
Buff Banded Rails may be seen scurrying along the
ground, and small, active Silvereyes feed in the trees. LADY MUSGRAVE ISLAND IS
Reef Egrets hunt all year on the reef flat and you may
IMPORTANT AS A BREEDING
also see them roosting and nestling in the trees. Many
migratory waders such as Oyster Catchers visit Lady SITE AMONG MANY BIRDS
Musgrave during Spring and Summer, leaving in Autumn
for their breeding grounds in the northern hemisphere.
The island is very important as a breeding site for
seabirds. Wedge-tailed Shearwaters or Mutton Birds the nest, after hatching the parents feed the chicks
nest in burrows in the forest. These burrows are located with fish. When the chick loses its down and feathers,
close to walking tracks so care should be taken. Noises of the parents fill it with food and depart, leaving the chick
their courtship and chicks calling fill the night during the to teach itself how to fly, thus resulting in many crash
summer breeding season. From the beach at dawn you landings. Each year the mutton birds will return to the
can watch their clumsy takeoffs before they soar over same place to look for the same burrow. With a little
the ocean. Birds in large numbers can be seen flying out renovating the same burrow can be used for years.
to sea to gather small fish, they return in large numbers
The other commonly sighted seabirds are the black
around 4.00pm and regurgitate partly digested food for
noddies, which build messy, flimsy nests in the Pisonia
their chicks.
trees. Both the Mutton bird and the Black Noddy will
Mutton birds dig a deep burrow, about 90cm deep, tolerate human presence, but the Roseate, Crested,
usually at the base of a Pisonia tree, with the nest Black-naped, Bridled Terns and the Silver Gulls which
constructed at the end of the burrow. One egg is laid in nest on the ground above high tide are easily disturbed.SHARKS MANTA RAYS
Sharks are important indicator of reef health, sign of a Manta rays are not only known for their grace and
healthy reef! beauty but play an important role in ocean nutrients
cycling and control plankton abundance.
Top predators: if there are sharks, then there are the
fish that they eat, and the fish that they eat, and the Also known as the devil fish because of the horn-like
fish that they eat, and the plants that they eat, all the mouth structures called “cephalic lobes” used when
way down the food chain. filter feeding. Manta rays differ from other ray species
in size, distribution, feeding strategies and unlike the
Sharks (especially reef sharks) are mostly scavengers,
stingray do not possess a barbed tail.
so they’re always looking for an easy meal. This
means they ‘pick-off’ all the slow, sick fish, leaving the There are two species of manta rays; the giant oceanic
healthiest and strongest to grow up and have lots of manta ray (Manta Birostris) and the smaller reef
babies, passing on ‘big and strong’ genes, and keeping manta ray (Manta Alfredi). The giant manta rays have
fish populations nice and healthy. This supports not a maximum wingspan of seven metres while the reef
only the ocean ecosystem but also our fisheries. manta’s can reach five and a half metres.
Most people are afraid of sharks until they find Reef manta rays are found around coastal areas in
themselves in the water with them for the first time. tropical and subtropical waters, mostly in the Indo-
Experience can change your perceptions, so keep an Pacific. The giant oceanica mantas are a circumglobal
open mind to the possibility that you may see a shark species found around the equator.
at some point today.
The manta ray is a filter feeder consuming large
They’re not man-eaters like the movies and media quantities of zooplankton through plates called gill
make them out to be (especially reef sharks!). rakers that are found in their ventral gills.
The closest most people have ever come to sharks The manta ray has few natural predators apart from
before is at their local fish shop. It’s marketed as killer whales and larger sharks. However both species
‘flake’. Most shark species are on the endangered are listed as vulnerable due to human activities
species list. including pollution, entanglement in fishing nets,
and direct harvesting for their gill rakers for use in
Using the App called the ‘Sustainable Seafood
Chinese medicine.
Guide’. Put any fish in and it will tell you with a traffic
light system whether a fish is ok to eat or not. “Red” Manta rays are graceful swimmers but also can be
= don’t eat me, our populations are suffering/low/ seen jumping out of the water, a behaviour known
unsustainable, “yellow” = if you have another choice, as breaching. A group of manta rays is known as a
it’s better to choose that, and “green” means go for it, squadron of manta ray.
our populations are healthy and it’s a good sustainable
choice. The guide helps you continue to enjoy eating
fish in a conscious, responsible way.GREEN
ZONES
Green zones have bigger fish
and more fish! They safeguard
protected species.
They support fisheries and are
like bank savings accounts –
a supply that gets so plentiful
that they overflow into places
you can take from.
Imagine what the island and
lagoon would look like if it wasn’t
protected or managed.
We use zoning to manage
the reef, but the traditional
owners have managed the reef
sustainably for thousands of
years (through storytelling and
living closely with nature).
During noddy land-mine
season: Dead/dying noddies
can come as a shock, probably
because most of us live in cities,
suburbs, or even on farms,
where nature is managed,
controlled or even out-of-sight.
This kind of sight is completely
normal and natural – it’s how
nature regulates itself when
it’s left completely untouched.
We are so privileged to see a
IT’S A PRIVILEGE place impacted so minimally
TO SEE A PLACE by humans. How often do you
get to see such a wild and
IMPACTED SO
natural site?
MINIMALLY
BY HUMANSREEF FACTS
1 3
At extreme low tide on the reef flat, many corals It is possible to determine the age of certain
are exposed to the drying air and hot sun. So coral colonies by taking core samples. Exposing
how do many corals survive this prolonged the core samples to UV light shows a varying
exposure? Corals secrete a mucus coating thickness and colouration in these bands.
to protect themselves and have a sunscreen The bands appear due to the fluorescence of
chemical to shield them from the ultraviolet chemical compounds that were deposited in
rays. Other more mobile animals retreat or move the skeleton during growth. The density and
into pools at low tide while anemones fold their intensity of these fluorescent bands provides
tentacles, molluscs shut their shells tightly. a measure of the environmental conditions
during the main growth phase of coral. The
bands may reflect the amount of freshwater
run-off that the respective reef experienced in
2 the past. The chemical compounds responsible
The reef is like a forest surrounded by desert. for the fluorescence of the layers are organic
Tropical waters are generally poor in nutrients substances that are being washed into the sea
(hence that turquoise clarity) and yet the during major flooding events. Given the long-
reef itself is a very rich garden. The secret of lived nature of Porites, (may reach 1000 years of
this incongruity is that nutrients are carefully age) individual colonies of this species may hold
preserved and efficiently recycled. Very little a detailed environmental record dating back
of value is allowed to drift away in the currents several hundred years.
but any nutrient in the incoming water is quickly
turned into living tissue. The resultant balance
of absorption versus secretion is finely tuned
— excess removal of nutrients by overfishing
or the increased introduction of nutrients by
some forms of pollution will tip the balance and
damage the system.
2019 BEST OF QUEENSLAND EXPERIENCE
AWARD WINNER
Contact Us
Shop 5, 15–17 Marina Drive,
Burnett Heads QLD 4670
+61 7 4151 5225
e: info@ladymusgraveexperience.com.au
www.ladymusgraveexperience.com.au
2018 2019 2019
WINNER WINNER WINNER
Tourism Visitor Tourism Visitor
Attraction Attraction Presidents
Business of Business of Award
the Year the YearYou can also read
