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The Great Crested Grebes of Maiden Erlegh Lake in 2013:
In 2012, for the first time in several years, there were grebes on Maiden Erlegh lake. I first noticed a pair of new arrivals on 19th or 20th March, and certainly there were two of them for the next few days. Throughout April, however, only one was in evidence, and I wondered, mid month, whether one was nesting. I was right, and on 15 March I saw the female on a cluster of twigs amid the low lying branches projecting off the north side of Big Island. But throughout the next couple of months, nesting appeared to be highly intermittent. Sometimes I would see just one grebe, sometimes one in the water and one on the nest. Sometimes I wouldn’t see one at all. There appeared to be little continuity in the nesting. This went on through May and June, until on Friday 29 June, at 9.30pm I noted, “The grebes have greblings (not sure how many)”.
Although for the next few days the youngsters were audible rather than visible, it soon became apparent that there were four. In these early days, the chicks would be carried around on the back of one of their parents, held in place by wings raised as gunwales. Throughout July and August, the pair raised their young, sometimes together, sometimes apart, but a family of six in total. At the end of August the growing chicks retained their stripy heads and still were piping whenever there was the prospect of being fed. The adults would call too, in a deeper rattling tone, though not so often. In September and October, there were fewer sightings and, it would appear, fewer grebes – just 2 or 3 at a time. The youngsters were getting bigger, and by October the juveniles were getting harder to distinguish from their parents. In November, single sightings were the norm, and in December none. The family, it would seem, had dispersed.
However, this departure was not for long and 2013 would bring a doubling of the grebes’ fecundity. On the 1st January there was a grebe – just one, but sitting on the coots’ nest on the south eastern ‘corner’ of the large island. Was this prophetic; a hint of what was to come?
Well, after an absence for the rest of January, a (the?) grebe was back on 2 February, and by 23 February there were two. On the 3rd March these were performing the grebe’s distinctive courtship display and on 28 March the female was on her nest – the same nest as last year – on the north bank of Big Island. Whether it was the weather, or the re-use of an existing site, this year’s occupation of the nest was two weeks earlier than in 2012. It was shorter, too. Compared with two and a half months to the end of June, this year’s brood appeared within the month. On Saturday 27 April the two were in the water, and it seemed as if one had newly hatched chicks on his/her back. The next day there was no doubt at all: the grebes had chicks. Counting them was tricky – obscured by protective wings, sightlines interrupted by constantly moving birds – but by the following weekend it was clear that there were four. Some were being carried, others swimming, but there were four in total. There was one scare when a hungry heron tried his luck, attacking the chicks at the lake end of Big Is, but he was driven off by the commotion caused by the protective parents.
By the end of May the family had diverged. Often three would accompany one parent up to the shallows near Swan Island, while the other parent would tend the remaining youngster in the lee of Big Island. As June drew on groups of chicks would go out unaccompanied, skilful divers now, but at other times a parent (seldom two) would be in attendance. But at the end of June the family was still intact.
In July the situation changed. With juveniles largely grown, the female took to nest again and on 10 July was sitting. There was now no sign of the first family, but a second would seem to be on the way! Throughout the rest of July and most of August, one grebe would be in the water and the other on her nest. Then, the summer nearly over, the second brood appeared. I’d had a hunch the mother’s time was up – six weeks had passed – and went to check the nest on Friday 23 August. No youngsters yet, but on Sunday morning both birds were in the water and at least two stripy heads were peeping over the wings of one of them. The nest was abandoned promptly and the new family relocated to the shelter of a tangle of overhanging branches on the southern side of the island, fed every few minutes by an industrious father on his return from fishing in the open water. (Interestingly a couple of coots would be seen picking over the grebes’ nest for their own purposes, as soon as it was vacated. There was no time wasted!) I wasn’t sure if there were two or more chicks in this second brood, but by 5 September was certain that there were three.
The pattern of swimming over to Swan Island was repeated: they were there as early as 8 September and, on the 15th, one of the chicks was there alone. The family continued to convene, however, and with one or both parents in attendance, took to gathering beyond Swan Island toward the Beech Lane end of the lake.
As October unfolds, at the time of writing, the juveniles are getting bigger than their parents, puffed up by the fluffiness of their down. That said their youth is revealed when the parents proffer a beak full of fish and they paddle frantically towards the older birds, their webbed feet rotating right out of the water and splashing noisily. And their cheeping can be heard even when the birds are not in sight.
What can we look forward to next? Will they over-winter? Can we expect three broods next year?!
Edwin A.R. Trout
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