Socorro Island’s high level of endemism (approximately 30% of species are endemic) is at risk due to invasive mammalian species. The endemic lizard, Urosaurus auriculatus, no longer exists in areas where feral sheep, Ovis aries, have destroyed the vegetation. The lizards can now only be found in patches of natural vegetation. It is estimated that 30% of the natural vegetation has been destroyed or eroded due to the introduced sheep.

 

Feral cats, Felis catus, have also been very destructive once introduced to Socorro, particularly for birds. The Socorro dove, Zenaida graysoni, went extinct in the wild in 1972 due to the introduction of cats just a few years prior. The sheep also caused a lack of understory for the birds. The Socorro mockingbird, Mimus graysoni, lives in low forest, making it particularly vulnerable to cat predation. They are now critically endangered and unlikely to make a population rebound unless the sheep and cats can be removed. Also contributing the the habitat loss of the mockingbirds is the locust Schistocerca piceifrons, which swarms and eats the leaves and fruits that the birds depend on.

 

Illegal fishing is also an issue for the ocean surrounding Socorro Island. The area is a designated UNESCO Biosphere Reserve, emphasizing the importance of conservation to maintain Socorro’s diversity and beauty. The Mexican government banned fishing completely in 2002, but enforcing the policy has been difficult due to the remoteness of Socorro. This complete ban of fishing has been criticized because small sportfishing boats used to provide valuable surveillance for large illegal commercial operations. The abundance of large sharks and rays attracts illegal finning operations and fishermen looking for giant manta ray meat. Not only does this harm the ecosystem and many vulnerable species, but it also reduces diving tourism, as many people come specifically to Socorro to see large pelagic animals. The Mexican Navy has partnered with several organizations to keep watch over the waters to stop illegal fishing.