MAGPIES, WONDERFUL AND WORRISOME BIRDS
Magpies belong to the crow family, and are thus highly intelligent birds
with a lot of individuality. The black-and-white magpies of the genus Pica,
that are the original magpies, have a holarctic distribution, although
missing from the eastern parts of N.America. Traditionally virtually all
the magpies in this vast area are united under the species Pica pica, in
English with their customary modesty called 'The Magpie'. The other
traditionally accepted species is the Yellow-billed Magpie of the Central
Valley of California ( and as far as I know never ever seen outside the
borders of this state), it is closely related to the more common species ,
called Black-billed Magpie in American, but i.a. has a greater tendensy to
live and nest in small loose colonies. These days, with the rise of the
Phylogenetic Species, many workers split up Pica pica into different taxa,
and then I suppose the Eurasian Magpie would be the Eurasian species and
the Black-billed Magpie the American one.
The Azure-winged Magpie Cyanopica of the Iberian peninsula is
an enigma,
as it only occurd here and in a small area of eastern Asia. It was long
thought that the Iberian population must be introduced, albeit long ago,
but recently fossil material was found in Spain, so the bird appears to be
indigenous there after all.
The excellent book The Magpies by T.R.Birkhead (Poyser, 1991)
gives an
answer to most of your questions about these fascinating birds, although it
only deals with Pica magpies..
Here in Tromsø, at 70*N, magpies are very common and very
well-known,
loved and hated; in Norwegian they are calle 'skjære' and here locally
'sjur', and there are any number of localities called Sjursnes or some
such. Magpies fill roughly the same role that I saw Currawongs fill in
Sydney---they are common also in populated areas, they are bold but very
wary, they are omnivorous, but hated by the smaller birds, because they
take a lot of eggs and young, and they are hotly accused of depressing the
population density of the more popular smaller passerines because of their
depredations, the argument being that humans provide so much food for the
magpies, directly or indirectly, that they can exist in much larger
densities than earlier, and this in turn depresses the numbers of small
passerines. Is not that exactly what people say about your Currawongs?
In reality research has shown that indeed the number of magpies has
increased substantially in towns and villages, and that the cause is a
combination of fewer being shot and indeed higher availability of food. (My
home magpies---as well as the Hooded Crows--- know exactly that the opaque
black bags that householders place out at the curb once a week (since the
authorities no longer empty bins that are further than 5m from the curb)
contain ----or rather used to contain, as we recently started refuse
sorting also here--- edible goodies. And one can therefore not place these
bags out a few hours in advance, as they are certain to be torn open, and
the contents scattered over the street!). The magpies indeed also take many
eggs and young, but none of the studies hitherto has been able to show that
magpie depredations is the limiting factor for passerine birds: in some
studies there was in fact no such decrease, in others there were other
factors (more disturbance, more cats, etc etc) that were much more likely
to be the culprits.
Magpies stay with us year round, and liven up the bleak winter days no end.
They profit to a large degree from feeding, although hanging feeders
usually defeat them. Their often enormous nests are a most characteristic
feature of our street trees (Not all that high at 70*N), while still
further north Magpies may nest on house-roofs or among telephone-isolators
on top of poles, as I also remember seeing in the treeless Anatolian
highlands forty years ago.
In early spring all the magpies of the neighbourhood come together in noisy
congregations that locally are called 'skjæreting' (i.e. magpie's
parliament); in my street I have counted up to 45 birds in these
gatherings. Later on the pairs always keep close together, with the males
guarding the females; magpies are monogamous, but we know from our own
society that that does not necessarily prevent trespassing and coveting
your neighbour's wife.
The 4-5 young are a very conspicuous part of the environment in late
summer, as they are loudly begging a lot of the time, and blundering
somewhat clumsily through the trees---they are roughly like their parents,
but have short tails. As soon as they have 'caught' one of the parents,
they beg with loud plaintive cries and opened wings; not rarely the parents
seem to have the responsibility for one or two youngsters each. The young
magpies draw a lot of fire from the Fieldfares that nest in a loose colony
in 'my' forest patch----these have their own fledged young in the area, and
do not seem to discriminate netween the relatively innocent youngsters and
the much more dangerous adults.
Magpies are noisy birds, with a large repertoire of mostly harsh calls. But
now and then one comes across one sitting quietly in a bush and singing
sotto voce for itself (That is the impression it makes and the sound does
not carry far either), and that is a surprisingly pleasant potpourri of
often quite melodious sounds.
Altogether Magpies are fascinating birds, and if they were not so common
many places, I am certain that people would travel far to watch these metal
shimmering long-tailed intelligent crows. But familiarity breeds contempt,
and contempt often inhibits seeing the true value of a bird.
Wim Vader, Tromsø Museum
9037 Tromsø, Norway
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