Common Ghost Crab (Ocypode Cordimanus)

Australia has six known species, of Ghost crabs.

These little crabs are so good at camouflaging with the sand, thus their name, making it difficult to see them during the day, if for whatever reason, they happen to leave their burrow.

Ghost crabs are found on open sandy beaches, where they live in their immaculate burrows, (some known to be more than 4 feet), near the intertidal zone, in the dry sand. They are nocturnal and remain in their burrows to keep cool during the day and warm during the winter.

They can hold oxygen in their air sacs for about six weeks, handy when you hide and live under the sand.

During the night, Ghost crabs, fix and repair their burrow and feed on a variety of plant and animal debris that has been washed ashore.  These omnivores can even catch insects in mid-air; due to their 360 degree vision, that allows them to see in any direction.

Ghost crabs breathe through gills, which they keep moist at all times, by various methods, such as taking the moisture out of damp sand.

An interesting thing to do whilst relaxing on a quiet beach is to listen for the Ghost crabs, very distinct, bubbling sounds! They use their gill chambers to produce bubbly sounds.

The female Ghost crab incubates 1000’s of eggs inside her flap, and once matured, these eggs become marine larvae.  Mum releases her offspring into the sea, where they remain for about two months before returning back to the shore.

Did you know that the Ghost crab’s burrows are regarded as valuable ecological indicators for quickly assessing the impact of human disturbance on beach habitats?  And, they can travel across the sand up to 10 to 15km/hr.  Yes, they are fast movers, and that is why they are so hard to catch.  Isn’t it interesting that their generic name is ocypode, which in Greek means, fast -foot.

I remember one day while I was drying off after a swim, I decided to read and relax, I saw movement in the corner of my eye, and I spied a tiny Ghost crab, well camouflaged with the sand, right next to a small burrow. I went to pick it up and it quickly fled into its hole. I started digging but there was no way in this dry sand that I could find it.  The crab had dug down so deep; apparently, they can construct long pathed tunnels, to who knows where… hence another reason for the name, Ghost crab.

Of course, afterward I realised I should not have dug into his home, all that work would have been destroyed.  I vowed not to do that again.  We need to be sensitive to the ecosystem that in some environments are quite sensitive, the softer our footprint is, in the natural environment,  the better for us all; flora, fauna, marine life, and us humans.

By M.A.Loveday ND (Lecturer and Guide on Wildlife/ Lover of Nature)

References: PDF Brazilian Journal of Oceanography 57(2):149-152 / Coastal Habitat Awareness Program –OCCI / Ghost crab a tool for rapid assessment of human impacts on exposed sandy beaches. ELSEVIER. Biological Conservation. F.Barros 97 (2001) 399-404 / Personal observations.

 

 

 

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Australia’s most loved crab – the Soldier Crab

Australian Soldier Crab (Mictyris Longicarpus)

soldier crab 255They feed on detritus, any small organisms, such as diatoms, gastropod eggs or nematodes that are found in the sand, leaving rounded pellets of discarded sand behind them. They start to  feed within fifteen minutes of emerging from their sand holes… feeding may last from one to two and a half hours,  then they aggregate into armies, with the largest at the front.

Soldier crabs are mainly seen at low tide before the crabs dig into the sand to wait till the next tide. Much of their time is spend buried in the sand and only emerging to the surface a few hours before low tide, some stay submerged for the entire tidal cycle.

The number of crabs which can emerge at a time is influenced by temperature, wind and rainfall, with the different sexes responding differently. For example, one day, nearly all the males emerge for the day, then the next day, there will be a mixture of male and female crabs.

Upon emergence, the crab performs ‘the most aerobic grooming performance’… ‘In less than a second the crab falls onto its back, to remove any sand, then flips upright again in a half a somersault.’

They live in sandy estuaries, beaches and intertidal mangroves, where massive groups of crabs seem to emerge from nowhere all at the same time.

By M.A.Loveday ND (Lecturer and Guide on Wildlife/ Lover of Nature)

References Wikipedia & personal observations.

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The Australian Pelican

In my book ‘Emily’ I have encompassed many messages of love, and this includes the love and appreciation of the natural environment, including the wonders and the beauty all that entails.  The wildlife that depends on the health of the environment, the flora and fauna that rely on each other, and the balance of all this and how  important this is to all our futures.  It is about love.

The first post is all about the quirky, Australian Pelican, or as us Aussie endearingly call them, ‘Peli’s’…

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Pelicans are a majestic bird found on every continent except Antarctica.  There are eight different species of pelicans in total.  The pelican commonly found in and around Australia is the Australian Pelican.  They have black and white feathers on their back, tail and wings.

Interesting facts

  • Males are generally larger than the females and can weigh up to 10 kilograms.
  • Have bluish/grey webbed feet.
  • They are the largest pelican in the world.
  • Australia’s largest flying bird.
  • Their lifespan in the wild is ten to thirty years.
  • Pelicans are communal birds that dwell together in large groups by bodies of water.  Groups of pelicans are called pods, scoops or squadrons.  They like to rest and nest together.  They will travel long distances to find where all their needs can be met: clean water, food, resting and nesting spots.
  • At night they like to go back to sleep at their favourite spots.

The pelican habitat is anywhere there is clean water, such as; sheltered bays and beaches, lakes and lagoons close to the sea and coastal swamps and rivers.

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Wings

The average wingspan of the pelican is 2.3 to 2.5 metres, at times reaching up to 3.4 metres. The pelican can fly to a height of 3,000 metres, and using thermals, it can reach speeds of up to 56 kilometres an hour.  They cannot endure long flights of flapping, so they fly from one thermal to another, with less effort for sometimes over 20 hrs.

Though they are considered heavy birds they have air sacs in their bones and under their skin, that contribute to their buoyancy.  The air sacs also improve their aerodynamics, by using these air sacs they can stiffen their wings and feathers, which make them more streamline.

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The Central Coast of New South Wales in Australia is a popular hangout place for Pelicans.

The Entrance is now been internationally recognised as, “The Pelican Capital of Australia”.   Why is this so?

It started over 25 years ago, when the ‘Fish and Chip’ shop across the road from the waterfront, fed the pelicans with their fish scraps and unsold fish; they did this every day at 3.30 pm.  One day the owners of the shop didn’t give them attention … and these very resourceful ‘peli’s’ decided one by one to jump out of the water, cross the road and head straight to the fish shop, demanding their handouts.

I (Margaret) remember seeing the ‘Pelican Feeding’ when I was a child and I am glad that this ritual still continues through the generations. It is such a sight, these beautiful wild birds are real characters, they just love to be given fish left overs and put on an act for everyone to enjoy.

So today, we can enjoy these Pelicans 365 days a year at 3.30 pm, putting on a show as they get fed with love.   In 1996, The Entrance Town Centre Management built the feeding platform for these pelicans known as, ‘Pelican Plaza’, and this is now sponsored by local businesses within and around the Central Coast. The attraction has also become a very important project not just to entertain and educate residents and visitors alike, but it has become a checking point for any injured Pelican.

Nearly every week they have rescued a pelican with a fishhook or from fishing line entangled somewhere on the pelicans body, or a boating accident.   On the weekend we attended the ‘Pelican Feeding’ with other friends and the commentator shared about a pelican that someone brutally injured; its pouch was cut and other parts of it’s body was injured. It was taken into the vet and has now been released back into the wild and healthy once again.

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Are they dangerous?

No, they will not chase or hurt anyone, or want to attack.  Sometimes you can even pat them,  they will quickly let you know if they don’t want you to touch them, and they will either;

  • Turn around walk away or fly away,
  • Make their bird sound and do the yawn and stretch with a scorchy noise, to let you know,  and
  • If you persist the Pelican can use its hook at the end of their beak to hurt.

Are they playful?

Yes, pelicans are often playful and curious animals. They have been seen playing with things like plastic bottles,  throwing them up in the air and catching them and doing that over and over; they have also done this with seaweed.  Sometimes they have trashed the bins to find a suitable play toy.

Diet

Australia pelicans mainly eat fish but they can eat turtles, crustaceans and tadpoles.  They have even been seen drowning and eating seagulls when in dire need or stealing other birds’ catches.

Australian pelicans like to hunt fish in groups.  They flap their wings against the water and glide skimming the surface in order to scare the fish to shallower water where they can catch them easily.  Pelicans can also sense their prey moving below the surface of murky water using their sensitive bill.  When eating a fish the pelican will manoeuvre it to go down its throat, headfirst so that the spikes of the fins do not damage its throat.

The Bill

The bill can be up to 40 to 50 cm long and it is recorded to be the biggest of all bird bills in the world

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Pelicans are known for their long bills, being forty to fifty centimetres long, but even more so for their large bill pouch.  The pouch is used for many things; it can hold up to thirteen litres of water and is good for scooping up fish.  When they scoop up the fish they also collect water in their pouch.  To resolve this, the pelican puts its head down on its breast to cause the water to flow out leaving the fish.  Pelicans can also use the pouch to cool themselves by swinging it from side to side.

When the female pelican is ready to conceive her bill turns reddish pink in colour, so the male can see her, as to spark an interest.

Breeding and Nesting 

They breed from the ages of 2 or 3 years, depending where they like to hang out, for example:

  • Winter – tropical areas
  • Spring –  South / East Australia
  • Anytime – After big rainfall inland areas

The pelicans nest is made out of feathers, leaves and sticks.  One to three eggs are laid and both the parents share the job of incubating the eggs. After 32 -35 days the eggs hatch.

While in the egg the pelican chick communicates with its mother, by messaging to the mother if it is feeling to hot or cold.  This communication before hatching is mastered and the unborn learns to take commands from its mother, forming a close bond, this then enables the new born chick to identify its parents.

The first chick is the biggest due to the fact that it receives most of the food and on some accounts even attacks or kills the other chicks in the nest.

When the chick is hatched it has a large bill, bulging eyes and its skin is in the appearance of bubble wrap due to the air pockets under the skin.  The baby’s faces are spotted and their eyes are any shade from white to dark brown.  Through these variations the parents can tell their own chicks from the hundreds of others.  After about a month the chicks are old enough to vacate their nests.  Creches are formed of about 100 young pelicans, where they learn to fly and survive; after two months of this they are independent.

Often Seen

Roosting on the rock platforms, jetties, sandbanks, swimming in lagoons, bays, estuaries and watch out,  telegraph poles!

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Written by Margaret and Sam – Wildlife Warriors, Carers and Lovers of Nature…

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Margaret’s book ‘Emily’, is available from Amazon, Barnes and Nobles, Angus and Robertson, and other online stores

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