The dragons of galapagos (1998)

This is the story of the incredible struggle for survival of the dragons of the Galapagos. On the island of Fernandina, each year Land Iguanas migrate up the steep slopes of the 5000ft active volcano to lay their eggs in the warm soil. If the rim of the crater is fully occupied they have to climb 1 km down the steep crater walls to the floor below. Many are killed finding a path down as the walls are steep & dangerously unstable causing many landslides.