Winter visitors
Now is the time to look for them:
by K. G. H. Munidasa
If you are interested in migrant birds, the ideal time to look for
them is during the last two months of the year; for by the middle of
November the vast majority of our winter visitors may have arrived in
the island.
They generally start arriving here in August or early September, when
cold winds from the Bay of Bengal begin to blow over, heralding the
onset of the North-East Monsoon. But it will be not until October and
November that the main influxes take place. During these two months
large numbers of wintering birds arrive from their breeding grounds in
distant parts of Asia and Europe.
There are in the island today roughly 427 different species and
subspecies of birds, and approximately 160 of these are migrants. And,
except for a few species of sea birds, all of them fall into the one
category; Winter Visitors.
Detailed studies on the subject of bird migration in Sri Lanka have
shown that a third of all the birds that winter in Sri Lanka are waders
and nearly as many belong to the Order Passeriformes.
From which countries of the world do these migrant birds come and
how? What are their migratory routes?
General observations made by ornithologists in this country and
elsewhere have disclosed that the majority of our feathered visitors
come from countries within the Temperate Zone.
Almost all the migratory waders seen in Sri Lanka have their breeding
grounds in Steppes and Tundra in the north of Europe and Asia. Such
birds as the Turnstone, Mash Sandpiper, Sanderling, Long-toed Stint and
the Caspian Plover may reach Sri Lanka from the breeding grounds in
Northern and Southern Russia, or even from places within the Arctic
circle.
The Brown-headed Gull and the Herring Gull, definitely come from the
larger lakes in Central Asia or from Russia, including Siberia, while
their smaller relative the Whiskered Tern come entirely from Kashmir.
The pintail, Garganey, Shoveller and Gadwall are some of the wild
ducks most of us know or some time or other have seen. But how few seem
to know the great distances they fly to reach our shores? The vast
majority of them come from places in the far northern regions of Europe
and Asia, and a few from Tibet and Mongolia.
The two commoner snipes, i.e. Pintail and the Fantail, hail from
places situated thousands of miles far apart. The first come in their
thousands from the East Siberian marshes, while the others come from
Northern Europe in moderate numbers.
The migratory waders - as many as eleven are known in Sri Lanka -
almost certainly come from breeding grounds in Eastern Europe and
Northern Asia.
The Indian Blue Chat, Pied Ground Thrush, Northern Orange - headed
Ground Thrush and Indian Blue Rock - Thrush would appear to come solely
from the Himalayan foot-hills.
So do some of the migratory flycatchers i.e. Blue-throated
Flycatcher, Layard's Flycatcher, and the Brown Flycatcher. It is certain
that the Indian White Wagtail, Eastern Grey Wagtail and the
Yellow-headed Wagtail too, come from their Himalayan nesting grounds.
The commoner Forest Wagtail arrives from its distant nesting grounds in
north-eastern parts of Asia.
The Indian Plaintive Cuckoo and Asiatic Common Cuckoo certainly breed
in the same localities as the above mentioned flycatchers and use the
same routes along the west coast of India to reach Sri Lanka.
The hawks and eagles visiting Sri Lanka during the North-East Monsoon
come from a variety of countries in Europe and Asia. The Siberian Honey
Buzzard has its headquarters in Eastern Siberia, while the Desert
Buzzard comes in from Japan or perhaps Burma.
The four species of harriers that occur in Sri Lanka have their
breeding ranges in northern parts of Asia and Europe. The Osprey and the
Short-eared Owl are birds of the Temperate Regions. The Red-legged
Falcon arrives in moderate numbers from breeding places to the
north-east of Asia, and the Kestrels fly into Sri Lanka from the Western
European countries, Japan and Northern China.
The Purple Wood Pigeon obviously comes from Bengal and Indo-China,
and the two Turtle Doves seen here during winter have their nesting
haunts from the Himalayas to Central Asia. The Blue-capped Kingfisher
and Tiger or Malay Bittern are considered as rare visitors, whose
nesting grounds have been traced to Western Sumatra, Burma and Malaysia
to China.
The arrival of a few other migrants is Sri Lanka is looked forward to
with more enthusiasm by the local bird watchers than the arrival of the
Common Swallow. It is one of the first to appear in our shores,
scattered flocks having been spotted as early as the third week of
August. It is also one of the last to leave the country.
The Blue-tailed Bee eater is also an early arrival. But it is not
always advisable to take for granted that every flock which one sees are
winter migrants, since this bee-eater lately been suspected to breed in
the wilder parts of the Eastern Province. However, the majority of this
bee-eater seen here in winter is probably migrants from the Indian
mainland.
The Eastern Grey Wagtail, perhaps the commonest and the most welcomed
visitor in the Central Hill Zone, may be yet another forerunner in the
long train of winter visitors. Immediately on arrival in the island it
betakes itself to the hill country and as a result its first arrival is
rarely or never recorded in the lowlands.
The sandpipers, curlews and plovers too, arrive in the late August to
early September. many of the smaller Passerine birds too, arrive in
September and early October. The Pintail Snipe generally comes in from
September onwards, but there have been instances when it had been seen
here earlier than this. |