Marine Iguana: (Amblyrhyncus
cristatus) The marine iguana is extremely common on all
the Galapagos Islands and lives exclusively on the rocky sea
beaches. Although the iguanas on each island look a little
different and are different in size, they are all the same kind of
iguana. The iguanas develop their colours as they get older - the
young are black, while adults can be combinations of black, green,
red or grey, depending on the island on which they live. The
iguanas on the Española island are the most colourful, with
blotches of red and green. The red colour comes from a kind of
seaweed that blooms in the summer.
They are vegetarians, feeding on seaweed on the rocks, in tidal
pools or in the sea. The biggest iguanas, generally males, swim
out past the waves and feed underwater. They dive about 1.5 - 5 m
down, but some very large adults can dive about 15 m or more.
Marine iguanas have the same features as other diving animals:
when they dive, their blood moves away from the surface to save
body heat, and their heart beat slows down drastically. Only the
largest males dive because larger animals lose less body heat.
Marine Iguanas live in large colonies for most of the year. In the
breeding season, usually December and January, they become
territorial. Males establish and maintain territories in the dry
places above the water line, and near the nesting groungs.