Marine iguanas in the Galapagos face welfare threats from El Nino events, introduced predators, and tourism pressure.
Marine iguanas during El Nino events experience progressive starvation as their algae food source declines from warmer water temperatures. Their unique ability to shrink their skeleton during starvation represents a remarkable welfare adaptation but cannot compensate for severe food shortage. Introduced predator removal programs protect iguanas and other endemic species from predation mortality and chronic predator-induced fear stress.