On the beach with turtles

by Derrick Schokman

Sea turtle survival is a numbers game. From the moment they are hatched and leave their beach nests to scramble frenziedly into the surf, the odds are firmly stacked against them.

Specialists believe that in an individual hatching just one in a thousand will reach adulthood. The remainder will be food for crabs, lizards, birds and fish.

Yet these creatures have survived nature's predators and kept going for millions of years. It is only in the last century that they have been threatened with extinction by humans, who collect their eggs and hunt them for meat and shell.

Endangered

All seven extant species have consequently been put on the World Conservation Union's (IUCN) red list of endangered or critically endangered species.

Among them are the five species that nest in our beaches: the Green Turtle (Gal Kesbewa), Hawksbill (Pothu Kesbewa), Loggerhead, Leatherback and Olive Ridley.

The females when they reach adulthood return to where they were born instinctively to propagate their species.

They are finding this increasingly difficult to do because undisturbed beaches are hard to come by where their nests are safe from plunder. The recent tsunami was another obstacle, but the good news is that the turtles are returning to the beaches.

Hatcheries

There is no lack of legislation for the protection of turtles and their eggs: its enforcement however is patchy and largely ineffective. In the absence of turtle reserves, it is impossible to police so many hundreds of miles of unprotected beach. Hatcheries have subsequently been developed as an additional means of protection.

It is a well intentioned idea, but only if the hatcheries are correctly managed on a scientific basic to meet the required biological needs of the turtles. If not, they could very well be self-defeating.

Turtle conservation by hatcheries is still very much a learning experience, but more information is becoming available about turtle biology that will help to manage hatcheries successfully.

It is now known for instance that temperature determines a turtle's sex. A nest within a temperature above 32 centigrade will produce virtually only females; under 27 Centigrade will produce just males. For a 50:50 sex ratio a nest needs to be between 29 and 30 Centigrade.

This brings into play the question of shading, which has to be adjusted according to local conditions to obtain the best results.

Ignorance of this biological requirement resulted in a steady decline of turtle numbers when hatcheries were first established at Terengganu in Malaysia.

Only females were probably produced and there were not enough males out there to fertilizer their eggs.

Yet another practice that is important, specialists say, is the relocation and transference of eggs from beach nests to hackery nests within three hours of the eggs being laid. Care should be taken not to rotate the eggs in the process of transfer.

Delays

Specialists are wary of the practice of delaying hatchling releases by keeping them in tanks before releasing them to the sea. They think this could disorientate their instinct to return and lay their eggs.

It has also been observed that delays weaken the hatchling. They take a longer time to reach the sea, and if they flip over in the scramble to do so, they take a long time to right themselves and sometimes not at all, thereby lessening their chances of survival.

Some hatcheries are also known to release the hatchling straight away in the sea, instead of allowing them to crawl across the beach.

This practice could also be disorientating and should not be encouraged.

Specialist believe that the early hours of the turtles' lives from nest emergence to entering the sea are critical and better left to nature's way of doing it without such interference.

Ancient

Sea turtles are a very ancient group of reptiles that have lived over 100 million years. They have seen the rise and fall of the dinosaurs. Having done all that it would be sad to see them disappear from our beaches. It behoves us to see that this does not happen. The State cannot do it alone. Enthusiastic individuals and organisations should be encouraged to set up turtle hatcheries. But only so long as they are licensed, and monitored for scientific management.

The first priority must be conservation and not tourist attraction. While it is an advantage that the major tourist season here coincides with the peak turtle nesting period, the disadvantage is that some hatchery operators are more interested in making money by indulging the tourists.

They expose the transplanted nests to display the eggs, and allow tourists to get a kick out of observing the hatchlings in tanks and releasing them to the sea at all hours of the day.

All these have a negative and even fatal impact on the normal development of hatchlings. If we are to do our part in the global effort to assure the survival of sea turtles, then we must do it professionally.