Today, all non-avian dinosaurs are long extinct. But are birds still considered to be true dinosaurs?
In a word: Yes.
– “Are Birds Dinosaurs?” LiveScience, January 20, 2020
It’s difficult to see a dinosaur in a chickadee or a titmouse, but the sight of a Great Blue Heron or Great Egret rising to flight evokes an undeniable Jurassic Park thrill. With their long necks and legs and impressive wingspans, it’s easy to envision them soaring over a prehistoric Texas. What a treat it is to still see them today, not only because they are dinosaurs walking (and flying) among us, but also because some have faced extinction much more recently. From Audubon Texas:
“In the late 19th century, Great Egrets were hunted almost to extinction for their plumes. Outrage over the slaughter of millions of birds sparked conservation movements across the country, eventually leading to the founding of the Massachusetts Audubon Society in 1896. Audubon’s momentum continued to build in the first years of the 20th century. Its members successfully pushed for the passing of the Lacey Act (in 1900), an important piece of bird conservation legislation that effectively stalled the millinery trade and brought many species of waterbirds under protection.”
Unlike their Great Egret and other large wading bird kin, Great Blue Herons, by and large, did not suffer quite the same level of slaughtered-for-hat-feathers fate. Indeed, as described by Sciencing, the bird “is the most widely distributed heron in North America. It is so plentiful that it is listed as species of least concern by the International Union of Conservation and Nature.” So, what, other than plumes to die for, differentiates egrets from herons?
Differences—or not—between egrets and herons (and a nod to the bitterns)
Fun fact: egrets are herons. They are both in the Ardeidae family but egrets are distinguished by their smaller size and white plumage. The word egret is from the French aigrette which refers to a plume of feathers. Unless you live in south Florida or the Florida Keys, exclusive home to the Great White Heron, if you see a little white dinosaur in flight, it’s probably an egret. American poet Mary Oliver famously described egrets as “a shower of white fire!”
Both egrets and herons fly with their necks retracted in what is commonly described as an S-curve, unlike other long-legged, long-necked birds, such as cranes, swans, and storks, that fly with their necks stretched straight out. As noted by Backyard Biology, “it’s all about center of mass…A large-bodied bird like a swan or goose or crane stretches its neck out when it flies to offset the amount of body mass it carries to the rear of its shoulder. Conversely, herons and egrets carry much less body mass behind the wing and are relative light-weights for such tall, long-legged birds. Therefore, they bring their heads back allowing the mass of the long legs to offset elongated head and bill.”
One more member of the Ardeidae family is the bittern. You may be less familiar with this shorter-necked family member as bitterns are notoriously secretive. As it prefers to blend into the background, we’ll leave the bittern in peace and beyond the scope of this particular blog.
Egrets and herons found in Texas
Texas lays claim to several herons and egrets. The Great Blue Heron, a highly adaptable wading bird, can be found across the state, from creeks deep in the heart of Texas Hill Country to Panhandle lakes. These modern dinosaurs can have wingspans over six and a half feet. Yellow-crowned Night-herons and Black-crowned Night herons along with Great Egrets, Snowy Egrets, Reddish Egrets, and Cattle Egrets also take up residence in Texas, among a few others. A “cool fact” about Cattle Egrets from All About Birds:
“Cattle Egrets are native to Africa but somehow reached northeastern South America in 1877. They continued to spread, arriving in the United States in 1941 and nesting there by 1953. In the next 50 years they became one of the most abundant of the North American herons, showing up as far north as Alaska and Newfoundland.”
A rookery by any other name
“A rookery is a communal nesting ground for gregarious birds consisting of anywhere from just a few nests to hundreds of nesting pairs in a relatively small area, where nests may be only a few feet or even just a few inches apart. While birds do not share individual nest duties, the collection of nests in a small area gives nesting birds and vulnerable chicks extra protection and advantages.”
– “Rookery – Nesting Colonies: How Colonial Birds Nest.” The Spruce, August 17, 2020.
Rookeries of herons are also called heronries. Does the distinction matter? Not particularly. But in a long-since abandoned blog created solely to complain about herons and egrets that had roosted in a Texas neighborhood and “the impact of the birds rights being placed over humans” the subject was the fodder for a passionate post:
The officials keep calling what we had a heronry instead of a rookery. Has anyone bothered to look at the definition?
Heronry – the breeding place of a colony of herons
Rookery – a breeding ground for gregarious birds
They need to call it what it is a Rookery!
Heronries or, ahem, rookeries have been considered nuisances by many (beyond enraged bloggers). The specifically named “Nuisance Heronries in Texas: Characteristics and Management” by Texas Parks & Wildlife addresses the subject:
“Some heronries are considered nuisances when located adjacent to residential areas and airports because of noise, odor, concern about possible health hazards (broken eggs, decomposing birds, associated parasitic insects, and diseases such as psittacosisornithosis, histoplasmosis, encephalitis, and arbovirus), and potential danger to aircraft. Also, heronries may produce detrimental effects upon nest and roost-site vegetation primarily because of the accumulation of excrement on the plants and substrata (soil and/or water). Furthermore, newly flighted young may alight in trees bordering driveways and yards situated near the heronry, and their excrement falls upon parked vehicles, yard equipment, lawn furniture, etc. In Texas, 33 nuisance heronries have developed in several towns and cities within 5 vegetational areas (Fig. 1), primarily the Post Oak Savannah, Blackland Prairies, and Cross Timbers and Grand Prairie.”
Are all heronries nuisances? In “In Praise of Nuisance Heronries (Part 2)” which covered a heronry on Bird Island in San Antonio, a follow-up to Part 1 which covered a heronry in the city’s Brackenridge Park, and both of which addressed the battles between bird protectors and those who want the birds cleared out, the author observes: “The nuisance of any heronry is in large part in the eye of its beholder, and its beholder often wants to live and drive and build and fly planes all over bird places.”
In the raging heronry battles, the Migratory Bird Treaty Act (MTBA) of 1918, has been a point of contention for those who want to mitigate the birds and a source of protection for the others. The more than a century-old act was reinterpreted in December 2017 by the current administration so that the law, created to protect migratory birds, did not apply to incidental killing or taking of migratory birds. One way this reinterpretation could be applied to heronries was explained by the vice president of bird conservation for the National Audubon Society:
“It is no longer illegal to engage in an activity that happens to ‘take’ a migratory bird (i.e., kill a bird or destroy nests and eggs) if the intent of the activity is not to kill the bird. For example, they could say they are thinning the trees on the island and it is too bad if they happen to incidentally to destroy a nest with eggs because it was not their intent to destroy the nest, only to remove the tree.”
But, interestingly, just last month, on August 11, 2020, a federal court struck down this 2017 interpretation and reinstated the act as it had been for 100 years. Some had called the MTBA a “dinosaur law” that was out of date and hailed the new interpretation, but as egrets and herons can confirm, dinosaurs don’t always go the way of the dinosaur.
For those interested in more about heronries…err…rookeries, Texas Parks & Wildlife has a video. Watch below or click here.
