The King Vulture is a really magnificent bird. The other three species are black in general, with different color of head and neck. The Black Vulture is commonly seen soaring around the country, but the King Vulture is not seen that often. However, when you see it, you are amazed. The juvenile is mostly black, with white underparts, while the adult is mostly white, with black wing secondaries and orange to red neck. Both have white irises, which contrasts nicely with the head colors. Immature adults retain some of the black feathers from the juvenile stage, showing an intermediate color pattern. The pink maw protrudes from the chest´s feather and is a very conspicuous feature, specially when the individual is full of eating meat. I am supposing that during hot days it helps to cool off by having it outside of the feathers.
The Black Vulture is one of the most commonly seen soaring birds in Costa Rica. They glide through warm air currents, congregate in numbers on a tree during the morning while waiting for the formation of those currents. They look for dead animals through their eyes, since their smell sense is not as acute. Due to that, they sometimes follow Turkey Vultures, whose sense of smell is well more advanced. As implied by its name, they are entirely black, with their face and throat bare skinned, which together with their scavenger nature makes for a disgusting reputation. They are admired though for their ability to eat contaminated food, which has been found to be derived from strong stomach acids and resistance to bacteria toxins. This is an important trait, as it enables them to act as recyclers, eating discarded food and turning it into fertalizer for the soil.