A great blue heron, left, and a snowy egret. Photos by the Associated Press

As a science communicator, sometimes one of my biggest challenges is making sure we are all talking about the same thing. This is especially true when we don’t use standardized names, and when colloquial names are used. Of course we can all learn Latin and start using binomial nomenclature, but it is a lot easier to say “great horned owl” than “Bubo virginianus,” no matter how funny the latter is.

In June, in this column, I took a deep dive into the confusion around what a “sea eagle” was, and with a recent email from Ruth in Gorham, I thought it’d be worthwhile to go over the difference between an egret and a heron. Is there really a difference?

Ruth’s question was primarily about distinguishing between egrets and herons, as she sees them on walks along the Eastern Trail through the Scarborough Marsh. I cut my teeth with Maine Audubon leading bird walks on that trail for six summers and can definitely give it a plug as one of the best places in the state for seeing those herons and egrets, plus ibis that nest nearby and many shorebirds that are now migrating south. More than 260 species have been documented along that stretch of trail through Scarborough, putting it in the top 10 “birding hotspots” in Maine based on biodiversity.

A good place to start with herons versus egrets is acknowledging how similar they are. The family Ardeidae includes all of the herons, egrets, and ibis, which worldwide covers 68 species in 18 genera. There are some pretty odd and distinct species around the world, but here in Maine there are only about a dozen regularly occurring species, plus a few that show up as vagrants.

That is about as clean as we can make any splits in their taxonomy, because the use of the terms “heron” or “egret” will start causing a bit of confusion. I often hear people call any of the larger Ardeids herons, but our two largest in Maine are great blue herons and great egrets. These do both fall in the genus Ardea, and (fun fact) that name is apparently a reference to the acidity of their feces. The account in “Birds of the World” points to a Roman myth of a town called Ardea, which was burned and from the ashes (instead of a phoenix) rose “a pale, lean bird, shaking the cinders from its wings and uttering mournful cries.” That myth was tied to stories of how these large herons/egrets have “burning” feces; after a nesting season, all the feces which have accumulated under the tree where their nest is can actually cause that tree to die.

Once we take a step down in size from the great egret and great blue heron, we find a few “egrets” and “herons” that are in the genus Egretta. You’d hope that Egretta would just equal egrets, but this does include little blue herons and the rare tricolored heron (some of you may remember them as Louisiana heron, but they’ve since been renamed). The name egret, or Egretta, comes from the French word aigrette, which is a specific reference to the feathers, or more precisely the headdresses, that would be made with them and often accentuated with rare gems. It does make me wonder which came first … but I digress.


To make things a bit easier, the simple way to know if you’re looking at a heron or egret in Maine is based on the color: great egrets and snowy egrets are all white, while the great blue, little blue, tricolored, and green herons are all somewhat colorful. Of course there are always exceptions to these rules, and astute birders will be quick to point out the confusion with young (1 to 2 years old) little blue herons, which are also white and can look very similar to snowy egrets. I’ve heard many people misidentify great egrets as “great white herons” but that is actually a unique subspecies of great blue herons which are generally restricted to southern Florida, Cuba, and the Yucatan Peninsula. Confused yet?

In bird identification, it’s hard to say anything too definitive because there are always exceptions to the rule, and as we’ve discussed, the ornithologists naming and classifying them didn’t help make this any easier.

That said, the short cut to remember: In Maine, if it is white, it is probably an egret. Then, if it has a black bill and yellow feet (golden slippers) it is a snowy egret. The reverse, a white (egret) that has a yellow bill and black feet, is a great egret. Almost everything else is a heron. And if it is really hard to see, it is a bittern!

Do you have a nature question for Doug? Email questions to ask@maineaudubon.org and visit maineaudubon.org to learn more about birding, native plants, and programs and events focusing on Maine wildlife and habitat. Doug and other naturalists lead free bird walks on Thursday mornings, 7 to 9 a.m., at the Gilsland Farm Audubon Sanctuary in Falmouth.

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