Grallatores

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A grey heron struts around a park.

THE above word defeated me in a recent newspaper crossword until I saw the answer in the next day’s edition. This is a rarely used word derived from the Latin ‘grallator’ meaning a stilt-walker. Today it refers to a group of long-legged wading birds such as Chinese egrets and herons. Chinese egrets, I have seen in Sarawak and also near a riverside kampung in Batu Pahat, Johor.

I recall a fascinating and authoritative article, ‘Saving endangered Chinese egret’ in thesundaypost of Aug 28, 2016, no doubt written by a member of the Kuching branch of the Malaysian Nature Society, based upon observations at the Buntal mudflats. Over the years I have enjoyed watching grey herons in my local river in Somerset, UK, as well as in Cambodia and Myanmar.

Grey herons

Fossilised versions of early herons have been found in Miocene aged rocks (from 23 million to five million years ago). All herons together with egrets are of the subfamily Ardeinae. First described by the Swede Carl Linnaeus, in 1758, he gave the grey heron its Latin name Ardea cinerea, literally translated into ash-grey heron. Ancient Romans revered this bird as its call signalled omens whether good or bad! Roast heron was a digestive treat in medieval English banquets and devoured with great relish.

Dimensions, colouration and call

Standing at a height of up to one metre, with a length of between 84cm to 102cm, and a wingspan of 66cm to 77cm, its weight varies from 1.02kg to 2.08kg. It has mainly ash-grey plumage and essentially a white head with drooping elongated feathers at the back of the head where a dark stripe punctuates the white. Its yellowish beak and long pinkish-brown legs make it a highly distinctive bird.

For many a year, I observed a pair of herons frequent and fish in the upper reaches of the River Tone in the UK. This river is relatively shallow in summer time with islands or aits exposed. I was first alerted to their presence by my dog as he ran along the river’s flood plain, thus disturbing one heron. I nearly leapt out of skin as this relatively large bird flapped its wings as it flew but a metre above my head and uttered a loud call of ‘fraank’. It landed and perched on the branch of a stag oak tree in an adjoining field and inquisitively watched my movements.

This heron became affectionately known in my family as ‘Old Nog’, a name I gave to him after it was first used in a book that I was given as a child. The book ‘Tarka the Otter’ was written in 1927 by Henry Williamson and is now a literary classic. Williamson, a naturalist, rescued and reared an otter cub near the banks of the Rivers Taw and Torridge in North Devon. This book begins, “Twilight over meadow and water, the eve-star shining above the hill, and Old Nog the heron crying kra-a-ark! As his slow wings carried him down to the estuary.”

With an average life expectancy of five years in the wild, my annual viewing of a pair of herons must mean that the ones I hope to see this year will be the fourth or fifth generation that I have sighted locally.

Diet

When hunting for fish, ducklings, water voles or water-beetles, a heron stands still in the shallows with its neck retracted and hunched against its body. This probably is to cast a smaller bodily shadow, on a sunny day, over the river-water and to swiftly recoil its neck in a spring-like fashion with its spear-like beak piercing its prey. Smaller fish are swallowed headfirst, ducklings whole but larger fish are taken to the riverbank to be stripped apart. Herons are the bane of gardeners with fish-stocked ornamental ponds.

Chinese egrets take to flight in a nature reserve.

Nests and nestlings

Tending to nest in heronries with up to 100 breeding pairs, herons are monogamous unless one or the other dies and a new partner is then found. Some heronries in the UK date to their first occupation in the early 17th century. Usually the same nest is used from year to year with winter storm damage repaired in the following summer. The male heron is the collector of nest building materials such as sticks, dead grass and reeds, which the female intricately weaves together.

Breeding occurs between February and June and, like egrets, a clutch of two to five eggs is laid at two-day intervals. Again like egrets, both male and female herons share the incubation period of about 25 days and once hatched both are employed in rearing their young. Feeding is accomplished by both male and female herons returning to their nest and regurgitating their stomach contents upon which the hatchlings feed on. After two months, the fledglings take to the air but, sadly, only 33 per cent of them will ever reach their second year of life as they fall foul to predators such as crows, kites, river otters and parasitic worms acquired through their diet.

Urban heron

Semi tame in London and Amsterdam, grey herons strut in parks and markets with a sense of purpose and authority. In Amsterdam, they feed off market stalls and poke their bills into waste bins behind restaurants. In London’s Regent’s Park, they patiently await to be fed from kindly passers-by bags of ‘goodies’. Much the same behaviour I have witnessed with egrets in Nairobi and in Kuching, where they strut around urban roadside drains and at roundabouts looking for garbage or else are frequently seen scavenging at waste collection landfill sites.

Ninety years ago

It was thanks to the ingenuity of a young Oxford ornithologist, who was disillusioned by what he termed as the Victorian leprosy of collecting stuffed species of birds, that the first group of fieldworkers were established in 1928 to study birds in their natural habitats through bird counts. His volunteers founded the then Oxford Bird Census which later evolved to become the British Trust for Ornithology. What bird did they choose for their first head count? It was none other than the grey heron for it was easily observed and also, at that time endangered.

This was known as the first Heronries Census, which is now in its 90th anniversary year. Later this year, I shall look out again for ‘Old Nog’ and his partner, or more likely their descendants, and report my findings to the Heronries Census, for every bird counts.

For further reading on Grallatores, look for thesundaypost article at theborneopost.com and also Henry Williamson’s book ‘Tarka the Otter’.