[This article was first published on the eBird Malaysia website].
White egrets are notoriously confusing for the novice and experienced birder alike, with their lack of obvious plumage features and variable ‘bare part’ (legs, bill and lores) colouration. Identifying them correctly largely depends on an appreciation of subtle differences in structure and shape, as well as a knowledge of their habitat preferences.
This article focuses on identifying Chinese Egret (Egretta eulophotes), a globally Vulnerable species with an estimated world population of fewer than 10,000 (BirdLife International 2017), and in particular, differentiating it from the main confusion species – Little Egret (Egretta garzetta) and white morph Pacific Reef-Heron (Egretta sacra).
Where and when to look for Chinese Egrets
The bar chart for the species on eBird shows that it is most frequently observed between September and early May, with just a very few ‘oversummering’ records. Little Egret and Pacific Reef-Heron, on the other hand, can be seen all year round.
In Peninsular Malaysia, small numbers are seen at a few localities along the west coast, such as the Klang Islands (Selangor), Parit Jawa (Johor) and the Teluk Air Tawar-Kuala Muda coast IBA (Pulau Pinang). Numbers are much larger in Bornean Malaysia, with Bako-Buntal Bay IBA (Sarawak) recording counts of almost 100 birds. A survey of the entire Sarawak coastline in 2010-2012 recorded a total of 637 Chinese Egrets (Bakewell, D. et al. 2017). In Sabah, Chinese Egrets can be regularly seen along the coast west and east of Kota Kinabalu, and around Sandakan Bay. A species map for Chinese Egret on eBird shows the distribution of records in Malaysia.
Chinese Egrets are largely restricted to intertidal areas on the coast, though they may gather to roost and occasionally feed in coastal aquaculture ponds in Sarawak. They do not habitually frequent rice paddies or freshwater habitats.
Little Egrets are equally at home in saltwater and freshwater habitats, and frequently occur in loose flocks of 100 and more in Malaysia. They also breed colonially locally.
Pacific Reef-Herons tend to occur alone or in pairs (often a dark morph bird is paired with a white morph individual). They prefer rocky and sandy shorelines rather than intertidal mud, and offshore islets and rocky outcrops. They do not occur in freshwater habitats.
How to find a Chinese Egret
The first step is to go to a place where they are likely to be found and at the right time of year (see above). Once you’ve done that, the key is learning how to tell them apart from the main confusion species, Little Egret and white morph Pacific Reef-Heron.
In breeding plumage (from late April), Chinese Egrets are relatively straightforward to identify, as they are the only egret to show a combination of yellow bill and black legs with yellow feet. They also have distinctive fan-shaped head-plumes, which are unlike the twin filament plumes of Little (Pacific Reef-Heron also has two short filament-like head-plumes).
Chinese Egret coming into breeding plumage, Sg Seria, Brunei, 28 April 2010
In non-breeding plumage, identification is more tricky.
Key things to focus on are:
- Bill shape and colour, loral skin and head-plumes
- Leg length and colour
- Overall structure
- Bill shape and colour, loral skin and head-plumes
Chinese Egret’s bill is dagger-shaped. The lower mandible is yellow for more than half its length, and the base of the cutting edge of the upper mandible is yellow.
The upper line of the loral skin (the skin between the eye and the bill base) kinks downward in front of the eye. This creates a distinctive expression even at a distance. The loral skin is grey-blue, becoming brighter blue in breeding plumage.
What’s left of the head-plumes are ragged and shaggy.
Little Egret’s bill is thinner and more parallel-sided, more pencil-shaped. The base of the lower mandible is frequently pale (this is seldom illustrated in books), but is pinkish or whitish, not strongly yellow. The upper mandible is all dark (this bird’s is covered in mud, so looks pale).
The upper line of the loral skin is more or less straight, creating a ‘bland’ expression.
Vestigial head-plumes are filamentous – one or two long, thin feathers.
Pacific Reef-Heron’s bill is heavier than and not as sharp as Chinese or Little. It is variable in colour, and can show the same rich yellow as Chinese. However, the yellow tends to be more ‘smudgy’ and less clearcut than on Chinese, and often the bill tip is yellow, which is not the case with non-breeding Chinese.
The loral line is more or less straight and the skin appears to go over the bill base.
The vestigial head plumes are typically two short filaments.
2. Leg length and colour
Chinese Egrets have mostly greenish-yellow legs in non-breeding plumage; they begin to become black in the early months of the northern spring.
Little Egrets usually have black legs and yellow toes, but juveniles can show greenish or yellowish legs (the left hand bird in this picture), which are a potential trap for the unwary. Photo credit: Neoh Hor Kee.
Pacific Reef-Herons’ legs are variable in colour. They are noticeably shorter than those of Chinese Egrets, especially the tibia. The legs also appear thicker than Chinese, especially the tibio-tarsal joint.
3. Overall structure
Pacific Reef-Heron (top photo) looks shorter-necked and legged and generally stockier than Chinese and Little. Chinese Egrets (bottom photo) are skinny-looking, more like Little Egret in overall proportions.
A Final Word
As with other species which are difficult to identify, the key to solving this puzzle is to base identification on as many features as possible, not just on one. These include habitat, time of year, numbers present and a combination of structural and bare part details. Photos are always helpful, especially in judging subjective details like leg length, and finer points like the shape of the loral skin.
Happy hunting!
References:
BirdLife International (2017) Species factsheet: Egretta eulophotes. Downloaded from http://www.birdlife.org on 20/01/2017.
Bakewell, D., Wong, A., Kong, D. & Au, R. 2017. Waterbird Surveys of the Sarawak Coast (2010-2012). [A Report by the Malaysian Nature Society-Bird Conservation Council (MNS-BCC) Waterbirds Group in partnership with the Sarawak Forestry Corporation]. Kuala Lumpur:
Dig deep 