Thursday, 11 August 2016

Bursting with bee-eaters

Juvenile Woodchat Shrike (Martin Kelsey
Two birds set the scene at the moment more than any others, by their sheer ubiquitousness and presence. And yet, each summer the almost constant companionship they give takes me by surprise. One is the Woodchat Shrike. On a drive recently through a terrain of mixed habitats, where patches of dehesa woodland were giving way to the plains, it was the most numerous bird to be seen perched on the roadside fences. They perch with a bolt-upright stance, looking bull-headed with a teasingly slowly wagging tail. From the top strand of wire, they are afforded sufficient height to scour the sun-baked earth, with sight evolved to see through the mish-mash of conflictingly-angled dead grass straws for signs of movement. The shrike drops from the fence, becomes immersed in the brittle cover and emerges with a cricket in its hooked-bill, returning briefly to the same perch before taking a bee-line, in typical direct flight away from view. This bird was a juvenile, as indeed are most that I see at this time of the year. Their plumage bears little resemblance to that of their boldly marked parents, looking a faded grey-brown, but beautifully scalloped with fine greyish bars. Only the pale creamy rump presages that of an adult. The species is a common bird here, but their abundance in late summer and the way young birds turn up and seem to take up temporary territories in areas away from typical breeding habitat (such as the edges of the rice fields, or indeed, our garden) suggests both a dispersal from natal sites and, perhaps, movement of birds from elsewhere as part of the gentle roll of autumn passage.

Unlike the Woodchat Shrikes, the Bee-eaters are in groups, sometimes forty or fifty strong, either bursting from low perches and hawking by swoops and glides over the pastures, or wheeling high above, mingling with hirundines, constantly making that pulsating referee-whistle prrrrt. They too are everywhere, moulting adults mixed with the young, less burnished golden above, more damp moss green.


Adult Bee-eaer on left and juvenile on right (Martin Kelsey)

Other birds too are amassing. On the Alcollarín reservoir near home I made four carefully-chosen stops, each offering me different angles on the water body, thus to survey the whole expanse of water, and to take into account the sun's position to enhance visibility, I picked a morning when the wind would be light enough to avoid the water surface becoming choppy. With my mechanical counter at hand I scanned the view, focusing on just two species which have been gathering in post-breeding groups here. Great Crested Grebes loafed languidly in loose parties, many with their long necks resting along their back, a position which accentuated their pale, rounded sterns and recalling flotillas of moored dinghies with sails at rest. I counted through these groups and added in as well the occasional solitary bird, or pairs of adults accompanied by their now large, stripy-headed young, still noisily begging as soon as a parent surfaced from a dive. There were 830 birds all told.

The Little Grebes were far more challenging to count. A few birds were scattered in ones and twos, but almost all were in one of five packs. Quite unlike their larger cousins, the Little Grebes reminded me frenzied nervous shoals, tightly packed, surging uni-directional, and able to switch course in apparent unison. Briefly they might pause and slowly spread out, but halfway through my count, the group would flex and tighten and start again a froth of submersions.   The most intense activity happened when the flock was close to a bank, in shallower water where presumably the small fish they were hunting where themselves more tightly packed. It seemed to me that the grebes were exercising a form of coordinated hunting, driving the fish into the shallows. This attracted Black-heded Gull and egrets which waited at the water's edge, as they do when cormorants perform in the same way.  There was unison in behaviour too when a Marsh Harrier sailed close along the water's edge. Almost all of the group of over a hundred grebes submerged as one, leaving me only being able to imagine the submerged chaotic scene, and having to wait until the grebes had regained a semblance of calm before resuming my count. The tally at the end of the visit was 585 Little Grebe, a remarkable total for not a particularly large reservoir. Like my musings on the Woodchat Shrikes, I wondered where they had all come from.

A pack of Little Grebes (Martin Kelsey)

1 comment:

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Good post, loved the way you explain the whole scene. Very well written and explained. Thanks for sharing it with us and keep posting such posts