Seeing Red on Christmas Island
Contributed by SeannaC
Most of my holidays revolve around diving, or a
place where I can at
least snorkel, and the colour dominating my thoughts is always blue.
Christmas Island’s waters are certainly that, crystal clear and a
strikingly deep cobalt blue. Like the Galapagos, Christmas Island has a
high rate of endemism
because of its isolation and three quarters of the island is national
park.
This time around though, a colour at the other end of the spectrum
filled my every waking thought in the days leading up to my trip to the
isolated island in the eastern Indian Ocean. All I could think about
was RED, and not just any red but that particular red which gives red
land crabs their name. It was my mantra, red, red, red.
And I wasn’t alone. There were many keen photographers,
videographers
and observers at Ethel Beach for the start of the annual red land crab
spawning on December 1. At the start of the rainy season millions of
mature red land crabs
migrate from their forest homes to the shore to mate, brood and release
their eggs. It is hard to fully grasp the scale of this epic
event
until you see it in person.
The timing of the spawnings depends on the rain, which triggers the
crabs to start their migration, as well as other conditions like the
moon cycle and tides. The crabs will only release their eggs before
sunrise on the full moon
and at the top of high tide so that their eggs are washed off the reef
under the cover of darkness. Spawnings last three to four days and the
female crabs stop releasing their eggs once the sun comes up and they
risk drying out.
Red land crabs were everywhere! From the footpath outside the
airport
to my hotel door, red land crabs were going about their business,
secure in the fact that this was their island. The crabs are protected,
as are many of the island’s animals, and many
roads are closed during the spawnings. Drivers are also warned to drive
cautiously and give crabs the right of way.
As we watched the natural event unfold by torchlight I heard one man
mutter to himself: “It’s the experience of a lifetime”. Witnessing the
culmination of a massive migration undertaken by millions of crabs is
an awe inspiring experience, yet I couldn’t help laughing at the female
crabs as they did their dance - the crab disco.
When a wave washed up the beach the crabs raised their pincers in
the
air, leaned back on their hind legs and then there was a whole lot of
shaking going on as they released thousands of tiny brown eggs into the
sea.
If you do travel to Christmas Island for the crab spawning, I highly
recommend staying on the island or return to see if the baby crabs
return (three to five weeks after a spawning). The eggs released during
the spawning go through seven larval stages in
the ocean before becoming miniature replicas of their parents. When the
baby crabs return en masse, it’s like their parents’
migration in reverse as the fingernail-sized crabs emerge from the sea
and cover the shore in a fine pink tide.
The baby crabs’ return depends on a
variety of factors such as
weather,
currents and predation, so each year varies. Last year was a good year,
while this year hardly any came back.
If you stay on after the end of the spawning, then you will also
have
much better access to explore the island’s many lookouts, hiking trails
and natural features such as the blow holes, the roads to which are
closed during the spawnings.
During the day, after finishing watching the spawning there is some
fantastic diving and snorkeling to keep you occupied.
As Christmas Island is at the top of an underwater volcanic
ridge, and
colourful coral reefs blanket the shallows and dramatic drop offs.
Gorgonians are found in just a few metres of water and near the
entrances to many of the sea caves as well as along the deeper walls.
Whale sharks, along with the red
land crabs, are the poster animals for
the island and can be spotted year round but most reliably over the
summer. Other pelagic species include manta rays and spinner dolphins,
which I was lucky enough to snorkel with five days in a row.