little blue heron - egretta caerulea, wildlife and birdwatching in costa rica

little blue heron egretta caerulea costa rica bird birding refugio vida silvestre cano negro birdwatching nature animal ornithology wildlife habitat fauna feather bill wild wilderness beak central america national park water wing plumage fishing green swamp wading river grey exotic tropical perched american conservation hunting lagoon marsh small genus egretta