Blue-crowned parakeets are not not native to the island, but managed to not only survive in the wild (after being released by humans or escaped from their cages) but also breed into a rather large population feeding mostly in urban areas. If you take the time to observe these groups you might me able to notice an interesting parakeet between them, without the blueish head and with a bright red patch on the front of the head.
Meet the scarlet-fronted parakeet (Wagler’s parkiet, Prikichi frente kòrá). These birds mingle with the Blue-crowned parakeets (the upper bird), fly together and even interbreed with them, producing hybrids with features of both species. Several hybrids have been spotted amongst the population. It is not entirely clear how many Scarlet-fronted parakeets are around, and there is no information available about the fertility of the hybrids. We do know from personal observations that the Scarlet-fronted parakeets have been around in the wild, longer then the Blue-crowned parakeets but somehow never reached the numbers of the Blue-crowned.