They are not nature’s loveliest creatures, but they deserve our sympathy and support. Here on Isabela they have 2 problems.
First, El Nino has warmed the waters hereabouts by up to 2 degrees. That has meant a major decline in iguana food. They eat only two species of marine algae, crops of which dwindle when the water gets too warm. Iguanas have survived these climatic events for ever, but according to a herpetologist we met here, the increasing frequency of el nino does not allow recovery of algal growth.
Iguanas have one very effective way of coping with starvation – they actually shrink. That includes a reversible decrease in bone size. Just imagine what humans could do with that capability.
The second threat to iguana population is the feral cat. Cats just love baby iguanas and are proving very difficult to eradicate.
So Galapagos iguana populations are dwindling and marine biologists are getting worried.
By the way, they are not spitting at us. They drink seawater and excrete the excess salt through special glands in their nostrils.