It was the breeding season. The snowy white Great Egret (Ardea alba) put on the beautiful “mating plumes”. Its exquisite beauty, unfortunately, brought about a tragic fate for the species from the late 19th to early 20th centuries, when its feathers were highly sought after as headwear ornaments. The fashion plume trade pushed the Great Egret population to the brink of extinction and, unwittingly, opened the first chapter of bird conservation movement around the world.
In Hong Kong, Great Egret is common and can be seen all year round. The wading bird has a slender body and a long bill, long neck and long legs. The long bill and neck allow the bird to forage in water—mostly after small fishes and shrimps—while the long legs are good for wading.
For novice bird watchers, one of the first lessons is to distinguish between Great Egret and Little Egret (Egretta garzetta). The two are very similar in appearance and form. The key difference is the colour of their bills and feet. Great Egret has a yellow bill and black feet, while the Little Egret has a black bill and yellow feet.
The situation with egret identification is, however, more difficult that this might indicate. In Hong Kong, apart from Great Egret and Little Egret, there are other egrets with white bodies—Intermediate Egret (Ardea intermedia), Eastern Cattle Egret (Bubulcus coromandus) and Swinhoe's Egret (Egretta eulophotes). Their bill and feet colour may also change in breeding season. Therefore, it does take experience to identify Great Egret correctly!
Building nest from scratch
Egrets like to live in colonies during the breeding season. They build nests that are closely packed on trees, forming an egretry. Egretry counts in Hong Kong started in 1989. There are basically five egret species in the local egretries: Great Egret, Little Egret, Eastern Cattle Egret (Bubulcus coromandus), Chinese Pond Heron (Ardeola bacchus) and Black-crowned Night Heron (Nycticorax nycticorax). In the three decades since the first survey in 1989, the numbers of Great Egret nests have increased from nil to close to 200. The reasons may be that water quality in the nearby seawater has improved, which increased food sources. Great Egret prefers to build nests near the sea and catch Anchovies and Grey Mullets for their youngsters. Regionally, the Great Egret population in Hong Kong is quite significant, as there are few Great Egret nests even in southern and eastern China.
During the breeding season, both the male and female will put on their eye-catching mating plumes—lush, fluffy feathers on the back in addition to their snowy white plumage. Egret is actually a name derived from the French work “aigrette”, which refers to the mating plumes.
Building nest from scratch
From the late 19th to early 20th centuries, it was an widespread fashion in the west for upper class women to wear real bird plumage hats. Among these, egret feathers became highly prized for the elegance and rarity—grown only during breeding season. This led to the extensive trade in wild bird feathers, and colonies of Great Egrets were wiped out. It was estimated that millions of wading birds were killed annually for the millinery business.
The massive slaughter of birds alerted some people, and gave rise to the early conservation movement. The National Audubon Society, which chose the stately Great Egret in flight as its symbol, was one of the earliest conservation groups founded in the U.S. to protect wild birds. The society mounted public campaigns to persuade women to stop wearing feathers on their hats. In 1900, the first Christmas Bird Count was launched as an alternative way of celebrating the festival to traditional hunting activities. With the growth of the National Audubon Society, the first National Wildlife Refuge was also established, and followed by more large-scale science-based conservation work in the U.S.