Like autumn
leaves floating in a sunlit pond, this vast expanse of magnificent stingrays
animates the bright blue seas of the Gulf of Mexico.
Taken off the
coast of Mexico's Holbox Island by amateur photographer Sandra Critelli, this
breathtaking picture captures the migration of thousands of rays as they follow
the clockwise current from Mexico's Yucatan peninsula to western Florida.
Measuring up
to 6ft 6in across, poisonous golden cow-nose rays migrate in groups - or
'fevers' - of up to 10,000 as they glide their way silently towards their
summer feeding grounds.
Magical: Golden Rays migrating in the Gulf of Mexico
They migrate
twice yearly: north in late spring (as pictured here) and south in late autumn.
There are
around 70 species of stingray in the world's oceans, but these cow-nose rays
(Rhinoptera bonasus) have distinctive, highdomed heads, giving them a curiously
bovine appearance.
But despite
their placid looks, they are still armed with a poisonous stinger, which can be
deadly to humans (even though sharks, their main predators, are more likely to
provoke them).
The stinger,
a razor-sharp spine that grows from the creature's whip-like tail, can reach
almost 15 inches in length and carries a heady dose of venom.
It was a
similar stinger that killed the hugely popular Australian naturalist Steve
Irwin in 2006.
Arc: The rays, swimming in a long line, was spotted by amateur photographer
Sandra Critelli
But even
equipped with this powerful punch, cow-nose stingrays are shy and
non-threatening in large 'fevers'. Even when isolated, they will attack only
when cornered or threatened.
Unlike other
stingrays, they rarely rest on the seabed (where unsuspecting humans can step
on them) and prefer to be on the move.
They migrate
long distances, and can be found as far south as the Caribbean and as far north
as New England.
They use
their extended pectoral fins to swim, and often turn upside down, curling their
fin tips above the surface of the water - leaving terrified
swimmers convinced that they have seen a shark.
Close up: The rays, properly known as Cow-nosed Stingrays, are known
because of their bovine-like high-domed heads
Their
flexible fins also come in handy when rustling up food. By flapping them
rapidly over the seabed, they stir up sand and reveal crabs, shellfish and
oysters, which they then feed on using their powerful, grinding teeth.
Their
particular fondness for shellfish has made them public enemy number one with
oyster fishermen.
But despite
this, their numbers are exploding, thanks in part to rising sea temperatures.
They mate every winter, and females produce a litter of five to ten young.
Stingrays
(which are related to skates and sharks) have never been widely fished for
food, mainly because of their rubbery flesh.
But barbecued stingray and dried fins are common in Singapore and Malaysia,
while pickled stingray remains a traditional favourite in Iceland. 'It was an
unforgettable image,' said photographer Critelli.