Adult whooper swan (Cygnus cygnus), pair on nest near Lake Myvatn, Iceland

whooper swan cygnus nest breeding season lake myvatn iceland wildlife nesting behavior waterfowl pair bonding natural habitat ecology avian birds nature conservation animal grassland tranquility adult swans beautiful outdoor parenting protection seasonal activity wetlands marsh fauna migratory biodiversity egg laying family instinct mating environment courtship feeding rituals young birdwatching ornithology