The proboscis monkey, endemic to Borneo's mangrove and riverine forests, faces existential threats from deforestation, particularly palm oil expansion, that are destroying the specific habitats this highly specialized species depends on.
Habitat fragmentation forces proboscis monkeys to cross increasingly dangerous landscapes between forest patches, increasing exposure to roads, villages, and predators. Deforestation causes population isolation and inbreeding in small remnant groups. Hunting for bushmeat continues in some areas. The species' specialist diet makes captive care almost impossible - individuals taken from the wild typically die within weeks. River development projects eliminate their travel corridors and crossing points. Each individual lost represents an irreplaceable part of a critically declining population.