Island Giants In most parts of the world, the largest land


animals are mammals such as elephants, moose, and bison. But on Aldabra, reptiles rule. Herds of giant tortoises, some weighing as much as 250 kilograms, roam these islands. In fact, Aldabra is the only large ecosystem where reptiles dominate the land. I never get tired of watching the giant


tortoises stretch their wrinkled necks to graze on leaves and grasses. T ese slow-moving herbivores help the ecosystem by fertilizing the soil with their droppings. T e result of their grazing is a short, grass habitat scientists call “turtle turf.” T e best time to see these gray giants is in


the early morning and evening. During the heat of the day, they seek shade under bristly bushes. If they are not in a cool spot by mid-morning, they may die.


King Crab For hundreds of years, sailors and traders


who visited Aldabra carried off the giant tortoises to eat or to sell in far away ports. By the late 1800s, the tortoises were nearly extinct. Recognizing the problem, early conservationists such as Charles Darwin worked with the local government to protect the tortoises. Since then, the tortoises have rebounded. Today more than 100,000 of these reptiles live on the islands. T ey make up the world’s largest concentration of giant tortoises. T e islands also protect another giant—


the coconut crab. T ese crabs are the world’s largest land-dwelling arthropod, or invertebrate animal that has a segmented body. Coconut crabs may measure as much as one meter across from claw to claw. Now rare on most islands in the Indian Ocean, armies of these crabs still clamber over Aldabra.


The pincers of a coconut crab are strong enough to open a coconut shell.


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