On my birding travels around the world Cattle Egrets were one species that hardly warranted a second glance as they were ubiquitous everywhere I went. In Africa, North and South America, the Far East and southern Europe they were seemingly always present, flocks of them in all sorts of open habitat and invariably associating with livestock or wild animals such as zebra, wildebeeste or buffalo.
Originally, Cattle Egrets were native to parts of Asia, Africa and Europe but since the beginning of the century their population has expanded rapidly and to such an extent they have now colonised most of the world and they are still increasing, the growth being facilitated by the expansion of farming which provides an optimum habitat of livestock and open terrain.
This growth in numbers has resulted in their colonising Britain where they were rare until the winter of 2007/2008, when there was a major influx and one pair remained to breed in Somerset.This was the first record of this species breeding in Britain and since then there has been a steady increase of breeding records and of others arriving in Britain. Somerset and surrounding counties in the southwest of England became their first stronghold and from there they have expanded into the southern and midland counties of England and also into Wales. Quite large flocks have now become the norm in the southwest of England, notably around the Somerset Levels. I myself can recall seeing a flock of twenty seven feeding amongst some cattle near the village of Shapwick, Somerset in September last year.
Even more exciting from a personal viewpoint is the fact they have now bred for the first time in Oxfordshire. At least five pairs were found to be breeding on a lake in the grounds of Blenheim Palace at Woodstock this year, successfully managing to fledge a good number of young. As a result subsequent months have provided reports of a variable sized roving flock of Cattle Egrets being found, usually feeding with cattle, in the countryside north and west of Woodstock and near Oxford.
For the last week or so a flock of seventeen Cattle Egrets have been feeding with cattle in fields at Wytham which lies adjacent to the ever busy A34, just west of Oxford. Yesterday the cattle were moved to a field that provided the opportunity to be able to stand close and observe the egrets from a path. I had little time to spend there yesterday and the light was fading so I returned earlier today, determined to see if I could get as close as possible to the egrets.
There were over seventy cows in the wet field and the egrets were scattered far and wide amongst them, usually singly. It was difficult to count them as the birds regularly disappeared or were already hidden in ditches or the rank grass and sedge but at regular intervals individual birds would fly up and move to another area, thus revealing themselves, whilst others would become briefly visible as they strode out of cover in their search for food.
Stationing myself on the path between the field and the A34 I stood and waited to see what would happen. Luckily for me individual egrets would be moving position at frequent intervals, flying up and then pitching down, shining white like windblown washing, above and amongst the cattle. It would only ever be a short interval before one or more would decide to move to another area that took their fancy, so there were plenty of opportunities to take pictures of them in flight.
The egrets were not particularly troubled by my presence, some coming close as they fed amongst the cattle that were stoically munching their way through the coarse grass. I had no idea what the egrets were catching but assumed they were feeding on invertebrates such as worms, beetles, insects and small vertebrates such as frogs, all of which the cattle would be disturbing as they moved amongst the grass. Each egret would loosely attach itself to one or more cows and follow, running to seize anything disturbed by the cows. The feeding looked to be good and some egrets even took time off from feeding to stand quietly on one leg, a picture of content.
I noticed one Cattle Egret showing an intense interest in the base of a largish clump of sedge.Its focus became more and more concentrated and it lowered its head as if listening, its neck outstretched, head and bill pointed directly at the clump. Suddenly it stabbed at the sedge and as it retracted its neck I was able to see that what I thought was a tuft of grass in its bill, was in fact a vole, possibly a Short - tailed Field Vole. I looked on fascinated as the egret held the unfortunate creature, still alive, between its pale yellow mandibles and shook and shoogled it around in its bill. After a few minutes of this violence and rough treatment the vole had succumbed and the bird manouevered the dead creature so it was pointing head first towards its gullet and with a couple of tosses of its head, the entire vole disappeared rapidly down the egret's throat. With a visible lump sliding down its neck the egret stood for a minute or two, with its yellow bill now stained with the blood of the vole.
Although mammals are not the staple diet of Cattle Egrets they are opportunists and will take live prey such as small birds and mammals if the opportunity presents itself. Cattle Egrets are in fact not as closely related to other egrets such as the Little Egret as they are to herons and I have seen many a Grey Heron catch rats and unwary birds. Later, I saw another egret that repeated the capture of a vole and speculated that maybe this is a good vole year and this was part of the field's attraction for the egrets.
I assumed the Cattle Egret would now stand for a while to digest its substantial meal but not a bit of it. A minute later it was off on a quest for yet more food.
How long this flock will remain here is anyone's guess but probably they will be here at least as long as the cattle are.The cold weather does not appear to affect them and as long as the feeding is good there really is no need to move on. It still seems strange though, to see them, en masse so to speak, in an unremarkable field in middle England when I so much more associate them with warm climates in foreign lands.
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