Blue-sided leaf frog
This frog is in danger of dying out for many reasons.  First, human beings build things and graze animals in the forests where they live.  Second, climate change is also changing their forests.  Third, there is more ultraviolet radiation than there used to be, and this hurts the frog.  Fourth, the disease chytridiomycosis.  Chytridiomycosis is caused by a fungus that did not come from South America.  People brought it there by accident.  Fifth, people also brought the fish Xiphophorus hellerii to Costa Rica.  This fish eats the frog's tadpoles.  Sixth, the fly Megaselia scalaris eats the frog's eggs.