Overall the article is well written. Not intending to be overly picky, but I have a few suggestions. (1) The 1st para in the lead could be a bit more concise. Example: The purple heron (Ardea purpurea) is a wide ranging, largely populated species of wading bird in the heron family Ardeidae. The Western Palearctic populations migrate between breeding and wintering habitats whereas the African and tropical-Asian populations are primarily sedentary, except for occasional dispersive movements; (2) Improve syntax to read, They are colonial breeders with a brief description of nest building rather than "takes place colonially with a bulky nest"; (3) possibly replace "a more secretive bird" with more evasive.....(3) Provide the IUCN Red List categorization which indicates the overall population trend is in decline.
2a. it contains a list of all references (sources of information), presented in accordance with the layout style guideline.
2b. reliable sources are cited inline. All content that could reasonably be challenged, except for plot summaries and that which summarizes cited content elsewhere in the article, must be cited no later than the end of the paragraph (or line if the content is not in prose).
