Herons and Egrets of Tobago
Faraaz Abdool discusses these elegantly shaped wading birds. If you enjoy his way of helping us to see birds, look for the newest birding publication on Amazon, Casual Birding in Trinidad and Tobago. All photos are by Faraaz Abdool.
Some of the most commonly encountered birds are members of the family Ardeidae, with their distinctive shape and gait. Often long-legged and long-necked, these lithe masters of the sit-and-wait are fixtures around coasts and waterways all over the world. This global family consists of around 63 species, of which more than a third has been recorded within Trinidad and Tobago.
Herons, bitterns and egrets share many of the same characteristics. They all have a long, pointed bill at the end of a long neck that is often held in an ‘S’ shape. When retracted, these birds look comically stocky – but let this not fool you. This is the proverbial coiled spring, the cocked gun, and the drawn bow – ready to let fly at a moment’s notice. That pointed bill is for impaling a wide array of smaller animals; individual species do have preferences but the process of food acquisition is fairly consistent throughout the family.
A Yellow-crowned Night-Heron
manipulates a crab before swallowing it whole.
Tobago has nine representatives from this family that are seen regularly. The egrets are the most conspicuous; all three species have completely white plumages. Cattle Egrets are by far the most ubiquitous and can be easily seen stalking open grassy fields and even some suburban gardens. As their name implies, they are often associated with cattle – they feed on the smaller creatures disturbed by the grazing animals. A white bird with a yellow bill and legs, the Cattle Egret is fairly straightforward to identify. Their all-white plumage changes substantially during their breeding season. Surging hormones cause these birds to sprout straw-coloured plumes from their head, neck and back. At the peak of their courtship, Cattle Egrets go one step further for a short time – the bill, legs and even irises turn bright pink!
Note the brownish plumes on this Cattle Egret.
Similar to the Cattle Egret but daintier, Snowy Egrets tend to stick to areas with more water. They can be found on coasts as well as along inland waterways. They have yellow feet but black legs; this gives them the appearance of wearing black pants and yellow boots. Snowy Egrets have wispy white plumes adorning their bodies in addition to their regular white feathers; this can give them a slightly windswept look. They feed on fish and other small aquatic life.
The largest of the three egrets found on Tobago is the Great Egret which is actually closer in relation to several of the larger herons than it is to the two aforementioned species of egrets. Its dimensions and behaviour are also more in line with these large herons. The only characteristic it shares with other egrets is its all-white plumage. Great Egrets are most often found near bodies of water, where they prefer to stalk the water’s edge for all manners of life – from insects to snakes to fish. Anything that can fit down their throat is fair game.
Note the rich rufous colour on the thighs and shoulders of this Great Blue Heron.
Closely related to the Great Egret is the similarly sized Great Blue Heron. While not entirely blue as its name implies, the Great Blue Heron does have a dark blue cap. The rest of its plumage is grey with a general bluish cast. A couple defining features are crucial in differentiating it from the much rarer Grey Heron: rufous thighs and shoulders. The corresponding areas on a Grey Heron are pure white. Great Blue Herons can be found in Tobago throughout the year, but during the northern winter their population is increased significantly by migrants from the north. Grey Herons are migrants from Eurasia and individuals that appear here are likely either inexperienced juveniles, or blown off course by rogue weather during their journey.
Much smaller and almost completely slate blue, the Little Blue Heron is a year-long resident of T&T’s inland wetlands and coastal areas. With a good view, the keen observer would be able to discern the purple wash on its head and neck. Having a similar diet, choice of habitat and hunting style as the Snowy Egret, both species often associate closely with one another – sometimes even choosing to nest communally in the same tree. Juvenile Little Blue Herons are completely white, and gradually replace their white feathers with the namesake blue as they mature. Their legs remain a greenish-grey colour throughout their lives, however.
Sometimes confused with the Little Blue Heron, Tricoloured Herons have a much more slender profile. While Little Blue Herons can seem a little chunky, Tricoloured Herons are sleek, blue and white herons with a yellowish bill that is tipped black. If viewed from below, the entire underside of a Tricoloured Heron is white. During the breeding season, their bill turns a conspicuous, bright blue.
The smallest heron on Tobago is the Green Heron. Formerly known as the Green-backed Heron, this small heron is well-known for its habit of using tools. Numerous birds have been observed luring small fish into striking range by using leaves and other small floating objects as bait. Once the fish come close enough to investigate, the heron strikes. They enjoy a much higher success rate using this method.
The group of night-herons is distinctive. They lack the sharply pointed bills of their relatives and often are equipped with bulging red eyes that aid in night vision. As their name indicates, they are most active at night – although they will certainly not pass up an opportunity to feed during daylight! Two species are found on Tobago: Black-crowned and Yellow-crowned Night-Herons. Both species use their thick bills to bludgeon the shells of their preferred crustacean meals they extract from inland waterways as well as coastal areas. Yellow-crowned Night-Herons are much more common on Tobago than the Black-crowned Night-Heron. Their genus name, “Nyticorax” translates to “night raven”, as a reference to their nocturnal habits and croaking vocalizations.
These opportunistic predators prowl our watercourses daily and while they may not seem as impressive as the regal looking hawks, they truly are models of patience. Their cryptically plumaged cousins – the bitterns – have never been recorded on Tobago, but they are notoriously well camouflaged and secretive, so who knows when the first one will be sighted?
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