Season means many different things to many people. Some
prefer monsoon for their crops to grow, while others look for summer for their
business to flourish. And there are people waiting for a new season to welcome visiting
birds. In fact, the avian visitors remind people of beginning of a new season.
The migratory birds’ spectacular flight reminds farmers to plant new crops in their field. Thus the saying in Nepali: "Karyang kurung aayo, kakro pharsi ropa" or, Here come cranes, plant cucumber and pumpkin in your nursery-lane.
The migratory birds’ spectacular flight reminds farmers to plant new crops in their field. Thus the saying in Nepali: "Karyang kurung aayo, kakro pharsi ropa" or, Here come cranes, plant cucumber and pumpkin in your nursery-lane.
When Hem Subedi, a birder and conservationist, sees numerous
White Wagtails flitting around, they inform him of arrival of Dashain festival–the
biggest festival of the Hindus, in October– and turning weather into colder
each day afterwards. He is expecting this winter to observe Ruff, Northern Lapwing, Falcated Duck and Eurasian Curlew, that are irregular winter visitors for Chitwan. Tek Bahadur Gurung, a nature guide and member of Bird
Education Society (BES), is really excited to see new visiting birds every now
and then during migratory season. He loves to share the finding among friends.
"It's like a festival for us", says Tek.
With touch of coldness on the air, birds start to arrive in
Chitwan to spend their winter holidays. Chitwan, a well known bird hotspot with
more than 600 species, attracts a huge number of migratory birds seasonally. According
to recent data of BES, some 147 species have been recorded as winter visitors
and some 61 species are summer visitors for Chitwan. The winter birds descend
down to warmer plains in the south from much colder areas in the north to avoid
the harsh weather condition and shortage of food; whereas the summer birds
travel towards north from south especially for breeding purpose.
Birds go for sojourn to the places where there is plenty of
food with less competition for resources; where they feel secure, and they have
perfect environment for resting, breeding and raising their offspring. Chitwan,
with all its abundant resources, provides perfect environment for birds that
visit during summer and winter.
Nepal's climate is governed by the monsoon, a seasonal wind
that draws moisture up from the Indian Ocean from approximately mid-June till
early October. It brings heavy rain and
snow everywhere except to the north of the main Himalayan Chain. In general
five seasons prevail in Nepal: autumn, winter, spring, pre-monsoon and monsoon.
The winter is mostly dry and cold from December to mid-February and the summer
period, covers partly spring and partly pre-monsoon, is generally dry and hot
from March to June.
Wintering birds begin to arrive in Chitwan from early September
and this trend is somewhat similar all over the plains of the country. They
come throughout mid-Winter and stay until February before they make journey
back home. White Wagtail, Greenish Warbler, Blyth's Reed Warbler, Common
Greenshank, Green Sandpiper and Common Sandpiper are among the birds that
arrive early. Many different species of ducks and water birds arrive in large
number during October - November.
Wintering birds start their journey from their breeding
grounds in the north – mainly Tibet, China, Cambodia, Laos and Siberia. While
travelling though high Himalayas, they follow the gorge; and most of them which
visit Chitwan come through Kali Gandaki Gorge that lies north-west from the
Chitwan Valley.
Members of BES, once recorded birds travelling from Lake
Baikal, Siberia. Hem confirmed, "Some 10 years ago, we saw a Black Stork
with a ring on the leg that led to investigation to find out the birds coming
from Lake Baikal."
Whole lots of birds migrate during winter but only few of
them spend time in Nepal. In fact, majority of them directly fly towards south,
parts of India and Sri Lanka. Many raptors do not come to Chitwan but go to
west through Mahabharat mountain range. Most of the cranes, stilts, ducks and
plovers directly make their journey towards south.
Those birds, which head towards far south, begin their
journey earlier than others. Most of them do not make much stopover on the
route. On their return journey, however, they make stopover at various places
in Nepal during March-April. They gather enough fat before they cross the high
Himalaya. Tika Giri, bird expert, elaborates that many flocks of Bar-headed
Goose can be seen in Koshi, an important site especially for waterbirds in far
eastern Nepal, during March-April. "They are, in fact, coming from south
to go north" he said.
White Wagtail, Blyth's Reed Warbler, Greenish Warbler,
Chestnut-crowned Bush Warbler and Ibisbill are among the birds that descend
down to plain from Mahabharat during winter. Tika emphasized, "These are
winter visitors but could not be referred as migratory birds. Migratory birds
are those coming from other countries."
March-April is regarded as the best period for bird watching
when you can see many wintering birds that are augmented by summer visitors. Chitwan's
climate in summer, when the day is longer and temperature is optimum, is
perfect for birds to come for breeding and raising offspring. They mainly come
from southern regions -India, Sri Lanka, Indonesia, Thailand, Malaysia and
Cambodia. Few birds such as Hooded Pitta, Lesser Cuckoo and Crow-billed Drongo
also come from as far as Africa. From June, these birds start to return back
with their offspring, except cuckoos. As their juveniles are raised by other
birds, cuckoos have luxury to depart early after laying eggs on other's nest.
Young cuckoos themselves travel back home following their innate sense.
Study and observation of wintering birds is going on as local
bird watchers, nature guides and members of BES are doing Mid-Winter Water bird
Census in and around Chitwan National Park annually in coordination of Bird
Conservation Nepal and International Waterbird Census. Recent observations
indicate that species diversity is good but population is decreasing. Certain
sites, where human disturbance is less, have more birds than others which are
more disturbed. Long stretch of Rapti and Narayani River, that forms the southern
boundary of Chitwan National Park, is still good habitat of both resident and
migratory birds. Some of the important wetlands such as Devi Tal, Lami Tal and
Tamor Tal inside the Park, and Bis Hazari Tal inside Barandabhar Forest
Corridor, which used to be favorable lakes for migratory birds, are fast
deteriorating by the invasion of alien plants.
The human induced threats to migratory birds are more than
ever that attribute to the decline of bird population. Hunting and associated human disturbance have been reported in areas where birds take temporary refuge during their journey. Global warming and climate change have their impanct on their great journey but habitat loss and
degradation are the major threats for migratory birds. Reduced food
availability due to over-fishing, poisoning, increased use of pesticides and
the spread of invasive plants in wetland areas has contributed immensely for the decline of bird population.
Birds are known as greatest travelers of all the travelling
beings. Indeed, they complete thousands of miles of journey. During the
journey, they apparently get tired and run out of energy. They need rest and
food to revive energy to continue the journey. So it is essential to protect
both habitats where they take refuge and where they spend whole winter or
summer.
We have culture of respecting guests as gods, "Atithi deva vawa". Birds are also
our guests. It is our responsibility to protect them so that they continue to
make their great journey unhindered, around the world.
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