The population of cactus dwelling birds will decrease and that of the animal they eat will increase.
Explanation:
When cacti is removed from the desert ecosystem, the birds that have their nest on the cacti will no longer have a home so they will migrate to other areas with favorable ecosystem.This will reduce the number of birds in this ecosystem.In turn, the animals that were feed by the birds will have the chance to multiply in numbers because a predator has been removed in the ecosystem.
