Hi Jon,
I have seen something today that is puzzling me and wonder if any other Bloggo readers may have encountered this odd bird behaviour. Like most people, I am aware that Magpies will sometimes gather and hoard any glittery and shiny objects they find, but has anyone seen them do this with food items?
Today I put some quite large pieces of bacon fat and other food out for the birds. Along came a couple of Magpies who settled down to eat and after indulging in a selection of peanuts and bread, one of them picked up a strip of the bacon fat, carried it up to the patio and promptly scraped a hole in the snow with its beak, dropped the fat in the hole and pushed the snow back over it, then moved a large dead leaf over the spot.
The same bird repeated this exercise twice more, digging holes, burying strips of fat and after refilling the holes with snow, covered the excavations with a dead leaf. At the third excavation there was no dead leaf close by so the bird jumped down onto the ice-covered pond and ripped out several pieces of decaying water iris leaves and carefully arranged those over the site of its stash.
Regards,
Syd.
Tim Birkhead’s exemplary monograph ‘The Magpies’ (Poyser, London, 1991) contains an entire chapter on ‘Feeding and food hoarding’. Here are a few quotations from his comprehensive account:
ReplyDelete“Food hoarding [also known as ‘food caching’] occurs in a wide range of mammals and birds, including several members of the crow family. This habit presumably evolved to allow animals to exploit food supplies which were temporarily abundant. Animals can eat only a limited quantity of food at any one time, and by hoarding the surplus they can reduce the chances of its being eaten by competitors.”
In a detailed study of Magpies in the Sheffield area, hoarding was recorded throughout the year “but was most frequent during the autumn and early winter, when fruit and seed crops are most abundant”. Of the food types hoarded, ‘domestic refuse’ (a category which included bacon rind, as hoarded by Syd Henley’s Magpie) formed 44% of a total of 305 observed items.
Incidentally, Birkhead remarks that “there is no evidence whatsoever that wild Magpies ever steal or hide anything other than food”, and Derek Goodwin (who observed both captive and wild Magpies) makes a similar comment in his ‘Crows of the World’ (BMNH, 1986). It seems that the thieving Magpie is another of those phenomena that ‘everybody knows’ but which is entirely untrue!
Thanks for the reply blueguitar, which I found interesting.
ReplyDeleteI have never previously noticed this food caching behaviour though it perhaps should not be totally unexpected of such intelligent birds. I happened to particularly notice this activity, as at the time I was working in the kitchen looking out onto the garden, so could not miss what was happening. The part that really puzzled me was the business of covering the site with a leaf, almost as if the bird was marking the spot for future reference.
With regard to Birkhead’s comment that “there is no evidence whatsoever that wild Magpies ever steal or hide anything other than food”, I would from personal experience have to disagree with him and say that so called experts and authors (in any field) are not always right.
Over many years I have often observed both magpies and crows in my large garden, playing with and hiding shiny and brightly coloured objects.
I have a rotary washing line and when it is removed, there is a bright yellow plug that fits in the top of the ground spike. Both Magpies and crows find this to be a real attraction and it has got to the stage where to stop them pinching it and hiding it under fallen leaves or in the compost heap, I have had to place a large stone over it. Another object they are fond of, is a stainless steel garden trowel with a bright orange handle. I have seen the Magpies dragging this around the garden and it is quite common to find it hidden under the privet hedge.
There is an Ash tree in the garden which has on occasion been used for nesting by Magpies and it is far from uncommon, when nests have been removed or blown down, to find assorted bits of coloured plastic, glass, silver foil, beer bottle caps, etc., among the nest remains.