Chapter Fourteen - Ascension Island 2010 Part 1

OK, I'll be honest, the project I've working on has, well, lets say turned to a great pile of steaming poo but that's not what this page is about, this page is about some of the things that weren't poo.

When you arrive on Ascension Island you'd be forgiven for thinking Why am I here ? Apart from work there's not many reasons to be there but one definite advantage to being on the island is the opportunity to see the Green Turtles, Chelonia mydas, nocturnal lumbering up onto the course grained sandy beaches, December through to May, & then later, February to June, the explosion of hatchling turtles from the sands as they head for the surf before the rising sun illuminates there passage & the islands many Frigate birds eat their fill. The frigate birds aren't the the only hazard of course, the blazing sun itself gets causes many to dehydrate, some just can't seem to find the sea & those that do make the relative safety of the water run the gauntlet of the Tuna who will happily feast on new hatch turtles, all in all the mortality rate is extremely high.

In years past there was a thriving economy based on the export of turtles for human consumption, the old turtle ponds around Georgetown can still be seen where the turtles were kept alive pending shipping, obviously this is now long outlawed & the turtles are now watched over by the local conservation trust as well as protected by international law.

The Green Turtle arrives at Ascension island after migrating some 1300 miles from the waters off Brazil, it mates just off the islands foreshore, it's not unusual to see a mating pair, drifting in circles as they struggle to mate, the males never come a shore but lazily patrol the islands waters on the hunt for females, individual females may come ashore several times over the season, laying up to a 120 or so golf ball sized eggs each time & maybe as many as 500 in total over the breeding season. When you walk the beaches at the height of the season it's not unusual to see eggs strewn across the beach which have been dug up by subsequent females excavating their own nests.

It has been discovered that the sex of the Green Turtle's off spring, like a select number of other reptiles, is determined by TSD, that is Temperature-dependent sex determination, simply this is a system in which the temperature the eggs are incubated at determine the sexes of the organisms that hatch, in the Green Turtles case the lower the temperature the higher the likelihood of all the hatchlings being male, the higher the temperature, all hatchlings being female.

When individual nests eventually hatch it really is an explosion, heads rapidly poke through the sand & they quickly emerge & congregate for a few moments as they orientate themselves as to the direction of the ocean, then as one they scuttle off towards the surf, as noted above for some reason the odd hatchling makes off in the wrong direction, confused maybe by lights from Georgetown, excessive use of torches or the moon obscured by clouds, whatever the cause, once they get it wrong it seems to stay wrong, pointing them in the right direction does not seem to make a difference, they still head off in a random direction so it's not unusual to see people, me included, collecting the waifs &strays & delivering them in to the water, it might not help them in the long term but it makes you feel just a little better about your self.

In addition to the Green Turtle a nice chap at the conservation offices suggested keeping an eye open around the Pier head for Hawksbill Turtle's, Eretmochelys imbricata, over the time I spent fishing AI's shoreline I actually managed see quite a few Hawksbill, unfortunately however they don't come ashore so I didn't manage to get any photo's, what did surprise me though was to find out that "Tortoise Shell" big in the 60's & 70's, was primarily the shell from the Hawksbill Turtle, given that the Hawksbill Turtle is now critically endangered I guess Tortoise Shell isn't very politically correct anymore.

Back to Antarctica