I receive several “what type of bird is this?” requests. I like helping out in that way and look forward to opening the email when I see that in the subject line. I like the challenge that I know is coming.

Sometimes the identification is easy, especially when a photo is included. Sometimes the identification is more difficult, especially when there is no photo included and I’m going strictly on a text description. I like those challenges, too.

I’m amazed at how often the unknown bird turns out to be a black-crowned night heron.

I received a letter from someone saying they saw a large bird by the water that they had never seen. The bird is described as being stocky, large, gray, short-necked or long-necked.

How can a bird be short-necked and long-necked at the same time? Like all waders, black-crowned night herons sometimes stand with their necks outstretched and sometimes with their necks curled against their bodies, giving them a stocky appearance.

Sometimes people recognize the black-crowned night heron as a heron. Sometimes they are mistaken for a duck. It’s a logical guess because the herons are always near water.

At dusk, black-crowned night herons can easily be mistaken for a gull, especially in flight. They are about the same size as our larger gulls.

The black-crowned night heron is a stocky wader with gray and blue plumage and brilliant red eyes. Adding an element of confusion to the mix is that immature birds are just as big, but have mottled brown plumage and orange or red eyes. Many field guides don’t include the immature plumage, so it really leaves a beginning birder hanging.

I was fooled by this when I was a novice birder. I was taking a guided walk along a small river in southwestern New Hampshire, when two large brown birds flew out of a tree overhanging the water. It was only a quick glimpse, and I immediately thought they were green herons. “What else could it be?” I thought to myself.

“Two immature black-crowned night herons,” the leader of the walk said suddenly.

Wow, I thought. I didn’t even know they lived around here. In fact, in that recollection I’m probably giving myself too much credit. I likely had never even heard of black-crowned night herons at that point. This was long before I had become familiar with the birds of southern New England along Long Island Sound, where black-crowned night herons are much more common.

It was on that same walk that I learned field guides can cause confusion in another way, too — by not including female plumage on the same page. We saw a group of about six large ducks on the river. They had dull white and gray bodies and light brown heads.

“Common mergansers,” the leader said.

I looked up “common merganser” in my field guide. I was confused. It showed a bright white bird with black markings, dark green heads and red bills. Another birder in the group, more experienced than I was at the time, told me: “That’s the male in the field guide. Those are females in the river.”

It was the last day I used that field guide.

But back to the black-crowned night herons. ... I think another reason people don’t know them is that they are overshadowed by their taller, more ectomorphic cousins. Everyone knows great blue herons, but not everyone is familiar with black-crowned night herons, especially people who do not live near water. Black-crowned night herons are mostly seen around brackish water, but are also fairly common around fresh water.

Another point of confusion is that they are just as often seen perched in trees near water as they are actually wading in the water. Great blue herons, by contrast, are almost always seen hunting in the water, or flying. They are seen perched in trees on occasion, but not as often as black-crowned night herons. It is a sight to behold, however, when you do spot a great blue heron perched at the tip of a towering evergreen. Indeed, that was one of the sights that took me from a casual watcher of birds to an obsessed birdwatcher and photographer.

That sighting is unmistakable. Almost everyone would recognize a great blue heron perched on the top of tree. Not everyone would know a black-crowned night heron.

They are not a favorite bird to many people, as, in addition to crabs and fish, they also eat young birds and bird eggs. The black-crowned night heron is worth getting to know, however. It’s an interesting and handsome bird that’s here to stay.

Chris Bosak may be reached at bozclark@earthlink.net or via his website, birdsofnewengland.com