Who named this bird and why? October 30, 2017

Posted by GGAS in Birding

By Steve and Carol Lombardi

So there I was, standing in a marsh staring at a bird that my Sibley’s field guide identified as N. nycticorax or Black-crowned Night-Heron. As I leafed through my field guide I found myself wondering where the scientific and English names came from, who decided on the spelling, why the scattered capitals, and really—who jammed those hyphens into the common name?

Of course, we all learned in high school how Carl Linnaeus invented binomial nomenclature in the 1700s, giving a Latinized Genus species name to every organism. Since 1895, the International Commission on Zoological Nomenclature (ICZN) has been the primary body for assigning scientific names to animals. (As you would guess, there’s an organization that names plants, too: the ICN.[1]) Thus, the history of the name N. nycticorax is well documented, and there is little argument about the bird’s scientific name, spelling, or capitalization.

However, it gets a little trickier when we start talking about common names. People have complained for hundreds of years about the lack of uniformity in common names of all living things. Yet there are only a handful of organisms whose names have been standardized by some organizing body.[2] Birds are one of these few.

Someone decided this would be a Black-crowned Night-Heron and not a Red-eyed Night-Heron. Photo by Bill Walker

In the United States, the American Ornithological Society (formerly the American Ornithological Union and still usually referred to as the AOU) maintains—and occasionally rearranges—the taxonomy of bird species in North America. Reputable American field guides and online sources like the Cornell allaboutbirds website use the AOU taxonomy. The AOU Checklists link each scientific name with one standardized English-language common name.

The AOU uses a detailed protocol to determine the naming, spelling, capitalization, and hyphenation of both formal and common names. Hence, the bird staring at me with its unsettling red eyes is listed in the seventh edition of the AOU Checklist as Nycticorax nycticorax with the standardized common name “Black-crowned Night-Heron.” Note the hyphenated “Night-Heron.” The first AOU Checklist in 1886, wherein they made the case for standardizing common names and spellings, lists the bird as “Black-crowned Night Heron” (no hyphen).[3]

First edition of AOU Checklist, 1886

Capitalization, then hyphenation.

The practice of capitalizing common names goes back hundreds of years in the scientific community. The AOU capitalized common bird names even before their first edition of the Checklist, yet newspapers and most other general interest publications insist on using lowercase for common names. The National Audubon Society was schizophrenic in this regard: Their scientific papers used caps; the Audubon magazine used lowercase until 2014—when they finally switched to caps after a lot of inner turmoil and some spirited discussion.[4]

So that leaves us to wrestle with the hyphens. “Black-crowned” makes sense since the word “black” specifies the color of the crown, not the whole bird. But why “Night-Heron?” For over a hundred years, the name “Night Heron” was good enough—until 1983, when the sixth edition of the AOU Checklist switched to “Night-Heron.”

Whose idea was that?

It turns out that in 1978 Kenneth Parkes (the Parkes of the Humphrey-Parkes molt theory) wrote an article suggesting some changes to the spelling of common names[5]. One of his recommendations was to hyphenate the “group names” of birds to help identify a portion of a taxa as a separate group. For example, presumably “Night-Herons” and “Pygmy-Owls” differ enough from other herons and owls to be considered a separate group. Parkes (and the AOU, since they adopted Parkes’ system) believed that denoting these groups through the use of a hyphen would convey some additional (presumably phylogenetic) information that was missing from “Night Heron” and “Pygmy Owl.”

Ferruginous Pygmy-Owl in Colombia, by Bob Lewis

The deployment of these additional hyphens was descried by many scientists immediately and continuously. For example, when the International Ornithologists Union (usually referred to as IOC) began to standardize common names for all bird species in the 1990s, they were blunt in condemning the use of hyphens to distinguish group names.[6]

But so far, the AOU has not budged—leaving our field guides littered with extra hyphens and confounding our bird ID apps. So there I was, standing in a marsh staring at a bird and scratching my head over the puzzling punctuation of its name. The bird calmly stared back and seemed not to care about my confusion.

“What’s your name,” Coraline asked the cat. “Look, I’m Coraline. Okay?”

“Cats don’t have names,” it said.

“No?” said Coraline.

“No,” said the cat. “Now you people have names. That’s because you don’t know who you are. We know who we are, so we don’t need names.”

Neil Gaiman, Coraline




[2] A bunch of Australians got together to standardize the common names of several thousand fish and other hydraulic organisms. Naturally, there’s an on-line database. http://fishesofaustralia.net.au/home/content/148

[3] Pages 68–69 of the first AOU “Check-List,” published in 1886: http://www.biodiversitylibrary.org/item/16484#page/7/mode/1up

[4] For a wonderfully entertaining account of this style change, read http://www.audubon.org/news/case-history

5] https://sora.unm.edu/sites/default/files/journals/auk/v095n02/p0324-p0326.pdf

[6] http://www.worldbirdnames.org/english-names/spelling-rules/hyphens/

Steve Lombardi is a long-time birder who gained most of his birding knowledge from taking GGAS bird classes. He has been GGAS’s volunteer Field Trip Coordinator for several years. Carol Lombardi is a birder and professional copy editor who keeps Steve’s sentences out of trouble.

Tags: American Ornithological Society, American Ornithological Union, AOU Checklist, bird names, ornithology, taxonomy.


  1. Scott
    November 15th, 2017 at 10:48 PM

    To Whom It May Concern:

    I found your email in an Audubon newsletter.

    Have you seen that they cut down the ficus trees that supported the black-crowned night heron rookery on 14th and Jackson?!

    Who is responsible for this?! We need direct action. I will do anything to help.

    In solidarity,


  2. GGAS
    November 16th, 2017 at 9:57 AM

    Thanks for your concern, Scott! We are working with the City of Oakland and the developers of that site to create an alternative, safer nesting site for the herons and egrets along Lake Merritt.

    As you probably know, the 14th Street rookery was not an ideal place for young birds. When herons that had not yet fledged fell out of their nest trees, they often faced injuries and traffic. With no understory of bushes, they were not able to climb back up into the tree to their parents’ care. Last year, we rescued over 80 young herons and egrets, and I am sure there were many more that we did not find in time.

    That site has been slated for development for some time, and the tree removal was part of that. We arranged for the developer and city to contract with expert heron biologists to identify safer nesting sites. This spring, we will work with them to use various techniques to try to attract the nesting adults to those sites. (One technique was saving some of the old nests from the trees that are being cut, and using them to “seed” the new site.)

    Of course, as with all wildlife, there is no guarantee that the birds will do what we want them to. We’re keeping our fingers crossed and hoping for the best.