Turtle power in Costa Rica
By Steve Backshall
Ostional is a four-mile stretch
of black-sand beach in northwest
Costa Rica. You probably haven’t
heard of it – not many people
have – but every year it plays
host to one of the most
dramatic, enormous,
mind-blowing, jaw-dropping
spectacles in nature.
Between June and December, for a
couple of days synchronised with
the phases of the moon, it is
home to the greatest aggregation
of reptiles on the planet.
They’re olive ridley turtles:
giant ancient mariners, their
heads encrusted with barnacles
and shells, bearing the scars of
shark bite and boat strike. They
congregate at Ostional to breed
and, soon after, the females
come ashore to lay their eggs.
Unlike other species of turtle,
they don’t sneak ashore silently
and solo, hoping to evade the
predators that would snatch
their eggs and hatchlings.
Instead, they arrive in
multitudes so awe-inspiring that
the predators are simply
overwhelmed. Once, 500,000
turtles were counted coming
ashore on this stretch of beach
in a 72-hour period.
The arribadas (arrivals) peak at
night and at high tide. We
arrived in mid-afternoon, at low
tide, and one was already well
under way.
Ostional is pretty impressive
anyhow. Fearsome waves crash
down on the black sand and, just
beyond the break, jagged
volcanic rocks send plumes of
spray into the sky like geysers.
Behind the beach is
uninterrupted rain-forest,
cloaking hills, then mountains.
Now, though, all the eye could
see was turtles: scrambling over
each other’s shells in their
desperate mission to find a
spare yard of sand in which to
dig their nest, battling up the
gradient and colliding with
their fellow reptiles heading
back out to sea.
Behind them in the breakers,
countless heads popped up from
the foam, in a holding pattern,
awaiting their turn.
Further up the beach, all that
was visible off into the
distance was a sea of wobbling
boulders chucking sand up behind
them. You couldn’t walk a pace
without stumbling over a
flipper. Huge gusts of sand were
propelled forcibly into your
pockets by their vigorous
digging. You had to be attentive
to prevent a disgruntled bill
taking off your foot.
My guide in Costa Rica was Julio
Rivera, naturalist and fixer
extraordinaire. Julio is an
amazing fellow: a mystical,
magical Latin American character
who left his family of 16
brothers and sisters at six
years old in order to walk to
the Caribbean “to find out if a
negro’s skin was painted and
would smear at the touch”. He
got his first pair of shoes at
age 15. As a young man, he
“died” after being bitten by a
ferde-lance snake, and was
brought back to life three days
later, convinced he had seen
God. After that, he did not cut
his hair for a decade.
Julio knows every plant, tree
and creature in this, the most
biodiverse country in the world,
and his wife has nicknamed him
“the Queen”, as his travels are
interrupted by continual waving
– everyone in the country seems
to be a personal friend. Julio
was responsible for getting me
here with such perfect timing,
to see an estimated 75,000
turtles come ashore.
Within a few square feet, you
can see every part of the
process taking place. One turtle
digs with her broad fore
flippers; another turns to scoop
out a deep well with her rear
flippers; behind the next, you
could watch the mucus-covered
ping-pong balls plopping into
the hole, then a turtle covering
them, and another waddling her
heavy carapace over the sand to
flatten it. You could even see
matchbox-sized hatchlings
flapping for the sea.
You couldn’t take a single step
without killing potential
progeny. Mind you, that was a
drop in the ocean. First, with
so many turtles nesting in one
place, single nesting sites can
get turned over as many as 30
times – one mother lays her
eggs, then another comes in and
digs them up while preparing her
own nest (the eggs all rot and
perish).
More dramatic still is the
predation. Flocks of vultures,
100 strong, sit behind the
mothers and peck up the eggs as
they drop. Dogs, raccoons,
coyotes, night herons and
majestic roseate spoonbills dig
up the nests and devour
everything. As the hatchlings
emerge from the sand, they have
to run the gauntlet of every
scavenger within a 50-mile
radius, all wanting to make them
into a light appetiser. The
local villagers take half a
million eggs every night from
the arribadas, then ship them
off to restaurants all over the
country. This is considered to
be a good thing – at least the
collections are well monitored,
and considered to be
sustainable.
Fewer than one in 1,000
youngsters will actually make it
to maturity. It is enough. Here
on Ostional beach, while the
predators sit too bloated to
move, a few hatchlings succeed
in that final scamper into the
surf and make their first
frantic splashes on the road to
majestic adulthood.
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