Another Life: Birds as foodies – a closer view

While blackbirds and starlings vary their menu, crows like to bury a little snack for later

The morning blackbird on our kitchen windowsill is an odd sort of Turdus merula. He calmly carries on eating squidgy melon seeds even when our eyes meet, up close, across the sink. He takes them one by one, instead of shaking them to death and splattering the window. For a change, he flies to the hedge and pecks at peanuts, having learned to hang on to the feeder, which blackbirds usually don't.

I haven’t seen him after worms because the grass has got too long. But it wouldn’t surprise me to see him hijack a worm from a song thrush, because blackbirds are notorious robbers as well as versatile snackers. The ability to switch foods rapidly is why the species has done so well.

A reader in Castleknock, Dublin, Joe Fagan, was watching blackbirds and starlings feeding on his lawn. While the starlings were eating small worms alive at a rapid pace, “unerringly accurate in their search,” blackbirds were much slower, hauling up larger worms and killing them before eating. He wondered about their comparative food intake.

What could be relevant is that starlings tend to speed each other up when feeding together, thus increasing the intake of the flock as a whole (this may also explain why they have to keep moving on). But starlings, too, have a wide menu. I sometimes see one perched on the back of a ewe, probing the fleece for ticks.

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Another reader, Larry Hynes of Galway, has been watching a magpie in the complex food-caching behaviour so typical of the crow family.

The bird in his back garden took a piece of bread and hid it under a leafy flower. “Then it took another bit and, pushing clay aside, buried the bread and covered it with a lump of clay and a stone . . . Then it took three bits of bread in its beak and hopped on to grass and forced the three pieces into three separate locations.”

Buried treasure

Early the next morning, he watched what he presumed was the same bird retrieve the first hidden morsel and eat it. He was “fascinated with the clear intent and precision of execution.” So, indeed, have been many ornithologists, compelled to grant the magpie, like raven and rook, an excellent memory for hidey-holes.

A friend recently brought me a posy from her garden, including twigs with the bright-pink racemes of the flowering currant Ribes sanguineum. Their sweet scent reminded me that the nectar of these flowers is often an eager choice for blue tits in early spring.

It has been years since a reader reported watching a blue tit pecking at the flowers. But one of the earliest observations was set down a whole century ago by the naturalist Charles Swynnerton, watching a blue tit in a garden in Larne, Co Antrim in the spring of 1914 ("Short cuts to nectaries by Blue Tits" in the Botanical Journal, 1916).

“Where a raceme hung well out [from the bush],” he wrote, “he would sometimes seize its end with both feet and probe the flowers by their openings as he hung there; but he far more frequently perched on the thickest peduncle, or on a neighbouring twig, and, continuing to hold this with one foot, stretched out the other (the left one always while I watched), and seized with it, as with a hand, the tip of the raceme and drew this in towards himself. Then, still holding and steadying it with his foot . . . he rapidly applied his bill to flower after flower.”

The tit’s attacks can leave fragments of shredded flowers littering the ground – this often a mystery to less observant gardeners. What has interested biologists is the role of nectar as a food source.

Studying the blue tits in a Belfast garden in the 1990s, Susan Fitzpatrick of the University of Ulster noted that "Nectar-feeding frequently occurred when the preferred peanuts were unavailable due to interspecific competition." There were no peanut feeders, I feel sure, in the gardens of Charles Swynnerton's time. But in suburban Belfast a mesh bag of nuts, renewed all winter, was hanging only 1.5 metres from the flowering currant bush and crowded busily with great tits, coal tits, sparrows and finches.

Her elaborate study (S Fitzpatrick, 1994, Nectar-feeding by suburban blue tits: contribution to the diet in spring) involved not only a close watch through binoculars from an upstairs window – this for 56 hours of one spring and 71 hours of the next – but a timing of the tits' visits to the nearest second, a daily count of open flowers, assessment of the nectar volume taken per minute and the energy value of its sugar.

Nectar, she showed, was “a highly profitable food source” while flowering lasted, contributing up to half the hen bird’s daily energy use. So, along with the nut feeders and nest boxes, a flowering currant bush sounds a generous idea.

Michael Viney's Reflections on Another Life, a selection of columns from the past four decades, is available from irishtimes.com/ irishtimesbooks