Surprise visitor on the beach

Here in Bunaken, Indonesia, we have seen many unique and rare visitors on our reefs, such as whale sharks, mola molas, hammerhead sharks, leatherback turtles, thresher sharks, orcas, dugons, sperm whales and even a guitar shark. The more hours you spend in the water the more likely you are going to see something unusual.

However, this time the surprise visit was on land. One late evening this March our dive guide Harli called us over behind the dive center where there was lot of noise coming from the bush and the whole two meter high plants were shaking. Something he first thought was his friend getting lucky, turned out to be a hawksbill turtle checking out a place for nesting. Earlier in the evening there had been high tide and the turtle's tracks showed us that she had came to the beach some hours ago when the tide was still very high.

It is yet unknown, but believed that turtles come to nest on the same beach where they hatched from the egg. Before they decide where to lay their eggs they will come up on the beach few times just to check out a suitable place for digging their nest. It has to be on dry part, high enough where even the highest tide with waves can’t reach the nest.

This 80 cm long, 50 kg heavy hawksbill turtle behind our dive centre probably realized that the sand or soil was too hard for her to dig a half a meter deep hole. Luckily there is a more suitable big stretch of empty beach next to Living Colours, where we have already seen some hawksbill turtle hatchlings few years ago. Normally turtles lay from 80 to 120 eggs and they nest every 2-3 years after reaching sexual maturity at about 30 years age.

Because of new moon, we had big tidal change and by the time the turtle was heading back to the sea, the mangrove air roots were already showing. The turtle got stuck in the roots and we had to go and bring her back to the waterline and guide her about 40 meters along the beach to the nearest boat channel from where she could finally swim back to the drop off.

Turtles mate in water where the male turtle attaches to the females back with its flipper claws and bites the female’s neck or front flippers. You recognize a male turtle from its very long tail, which it uses for holding the female on place during copulation. Females mate with many different males to keep the genetic diversity high. After laying eggs on the beach, the incubation takes about two months. Only one out of hundred eggs will survive to reproduce again.

Turtle's life is very dangerous and difficult from the egg stage until adulthood. The eggs are delicacy for monitor lizards, ants, grabs, monkeys, dogs, raccoons and some humans too. When the eggs hatch and the hatchlings are trying to run to the sea they get eaten by crabs and birds. Once in the sea many hungry fish are waiting for them. During their first years they will drift with sea currents floating on the surface, where they will be an easy prey for birds. They will feed on small jellyfish, too many times mistaking plastic for their food. Once a hawksbill turtle reaches 30 cm in size they will settle to live on a coral reef and feed on sponges, anemones, squid and shrimp. Adult hawksbill turtles can grow up to 70-100 cm long and only large sharks can prey on them.

Text by Annika Hartell, Photos by Annika, Jaakko and Micky