No? Well
let us see if we can sort that out for you!
First
to the stage – the green turtle (Chelonia
mydas):
Length: Can grow to an
average size of 1.5m (5ft)
Weight: Can weigh up
to 317.5kg (700lb)
Description: Green turtles are named for
the unusual green fat that resides under their carapace and are found in
shallow tropical and subtropical coastal waters. They have a dorsoventrally
flattened body (a body that is flattened from top to bottom like a pancake)
that is covered by a tear-drop shaped carapace with a scute pattern of 4,5,4. “Scutes”
are the plates on a turtle’s shell. Green turtle shells have 4 scutes along
each side and 5 scutes down the middle (see the diagram below). The carapace is
coloured with flecks of green, brown, white and gold which gives it a mottled
effect underwater. Unlike the other three species found here, the green turtle
has a small unhooked beaked head at the end of a short neck.
Diet: They feed mostly
on a variety of seagrasses.
Track pattern: When females crawl on to
the beach, their tracks are very large and symmetrical in pattern. This is
because female green turtles move their front flippers at the same time when
crawling on the beach (like swimming the breaststroke). Green turtle nests are
characterized by a very large pit (hole) and mound of sand.
Hatchling ID: Hatchlings tend to be
grey in colour with the same 4,5,4 scute pattern. They are distinctively
identified by their white underbellies and trailing fin edges. They tend to be about 5cm (2 inches) in
length and weigh around 25g (0.05lb).
Favourite saying: “You
so turtely rock dude!”
Next
to take the stage is the loggerhead (Caretta
caretta):
Average length: Can
grow up to 1m (3ft)
Weight: Can grow up to
113kg (250lb)
Description: Loggerheads, so called for
their distinctive large beaked head and thick neck, are found in temperate and
tropical regions inhabiting both oceanic and near shore habitats. They have a
slight heart-shaped carapace with a scute pattern of 5,5,5, which tends to be a
reddish brown in colour while their neck and flippers tend to be reddish brown
on top, but pale yellow underneath.
Diet: The loggerhead is predominantly
carnivorous with a very powerful set of jaws used to feed on
crustaceans, whelks, and commonly conch.
Track pattern: When females come up
onto the beach to nest their tracks are asymmetrical in pattern. This is
because they move their front flippers alternatively, like swimming the front
crawl. Loggerhead nests are small and scrappy compared to green turtle nests.
Hatchling ID: Hatchlings tend to be in
dark brown to grey in colour with dark or sometimes pale yellow underbellies
(in contrast to the white underbellies of green turtle hatchlings. Again they
have the same 5,5,5 scute pattern as adults and they are generally around 4cm
(1.5 inches) long and weigh about 20g (0.04lb).
Favourite quote: “Does this conch make
my neck look big?”
And
last but by no means least – the hawksbill (Eretmochelys
imbricata):
Average length: Grows up
to 65-90cm (25-35inches)
Weight: Can grow up to
45-70kg (100-150lb)
Description: The hawksbill is smallest
turtle found nesting and residing in the Cayman Islands. They have a long
elongated head that tapers down to a sharp beak point, and are found in seas
associated with a healthy coral reef system. They have a distinctive shell pattern,
where the carapace is dark golden brown, with streaks of orange, red and or
black with overlapping scutes in a 4,5,4 pattern and serrated edge at the back
of the shell.
Diet: Being associated with a healthy
coral reef, hawksbills feed on coral, algae, invertebrates and their favourite,
sponges.
Track pattern: When females come up
onto the beach to nest they have an asymmetrical crawl pattern. It is very hard
to identify the difference between loggerhead and hawksbill tracks. However,
from personal observation, the hawksbill track tends to have a very distinctive
tail wiggle through the entire up and downward track, and the hawksbill tends
to nest in areas of vegetation. Definite species identification can be made
through night-time tagging surveys or by examining hatchlings or embryos after
nests hatch.
Hatchling ID: Hatchlings tend to be in
dark brown to reddish brown in colour with dark brown underbellies. Again they
have the same 4,5,4 scute pattern and are generally around 4-5cm (4-5 inches)
long and weigh 15g (0.03lb).
Favourite quotes: “Really, another picture...fine...
all I wanted was to have my lunch in peace and quiet!”
And
that’s that folks! Remember these key identification points: 1) the number of
scutes, 2) the head and beak shape, 3) are they eating and if so what? And
finally 4) track patterns (if you are lucky enough to stumble across a turtle
or turtle track on the beach).
So why not impress your friends with your
new found knowledge!
Until
the next blog!
Luc :)
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