Large numbers of C. n. darwini were removed from Santiago Island in the early 19th century by whaling vessels, and introduced goats reduced the coastal lowlands to deserts, restricting the remaining tortoises to the interior.

The sex ratio is strongly imbalanced in favour of the males, and most nests and young are destroyed by feral pigs.

Some nests are now protected by lava corrals, and since 1970, eggs have been transported to the Charles Darwin Research Station for hatching and rearing.

Release programs and measures for nest protection from feral pigs have been successful.

[citation needed] The diet of the C. n. darwini consists of cacti, herbs, and grass found on Santiago Island.