Galapagos Tortoises Are a Migrating Species

ScienceDaily (Nov. 27, 2012) — The Galapagos giant tortoise, one of the most fascinating species of the Galapagos archipelago, treks slowly and untiringly across the volcanic slopes. Scientists of the Max Planck Institute for Ornithology in Radolfzell, together with the Charles Darwin Foundation, have used GPS technology and modern 3D acceleration measurements to find out that especially the dominant male tortoise wanders up to 10 kilometres into the highlands of the island. Only the fully grown animals migrate, the young tortoises stay year round in the lowlands. The reason for this and the question of why the animals don't rest during the dry season are not known yet.

The large, dominant male Galapagos giant tortoises usually start their annual migration at the beginning of the dry season.

Even Charles Darwin anticipated that the giant tortoises wandered large distances. In the cool dry season, the highlands of Santa Cruz are engulfed in fog which allows the vegetation to grow despite the lack of rain. In the lowlands, however, there is no thick layer of clouds and the tortoises' vegetation is not available year round. Adults, which can weigh up to 250 kilogram, spend the dry season in the higher regions at an elevation of 400 meters above sea level. However, since the food is not as nutritious there, they trek back to the lower zones where there is succulent vegetation in abundance as soon as the rainy season begins.

Continued:  http://www.sciencedaily.com/releases/2012/11/121127094105.htm