Around 2,000 birds, from over 30 countries fly from the Arctic to Singapore every year to escape winter’s cold. This amazing natural phenomenon is created from an instinctive understanding of many things – the length of days, the earth’s magnetic field, the night sky, natural landmarks … all this forms the basis of a round-trip journey almost 14,000 kms long.
Tracking devices attached to five species – the whimbrel, the common greenshank, the common redshank (from the Qinghai-Tibet Plateau, China) and the Pacific golden and grey plovers (from northern Russia, close to the Arctic Circle) reveal that the birds often stop at inland and coastal wetlands in Malaysia, Thailand, Vietnam, Myanmar, China, North Korea and Russia on their way.
Nature and bird lovers will be delighted to learn that NParks endeavors to ensure Singapore remains a conducive stop-over point for migratory birds.
- Water levels in ponds @ Sungei Buloh are manually controlled to provide high tide roost sites and overgrown vegetation regularly removed to provide open spaces for migratory birds.
- Buffer zones and complementary wetlands (Kranji Marshes, Mandai Mangrove and Mudflat) are maintained.
- NParks also works with its counterparts in Hong Kong and Malaysia to exchange information on migratory patters and requirements of shorebirds.
All about Migration
Why do they migrate ?
- Food availability is one of the main reasons, while weather and habitat changes also weigh in.
- In winter, the birds migrate southwards and in spring, most of them return north to their breeding grounds.
How do they find their way ?
- The position of the sun acts as a compass.
- The position of constellations in relation to certain stars like the North Star in the evening sky also works as a guide.
- A mineral called magnetite present in their beaks may help them to navigate using the Earth’s magnetic field, which tells the birds which direction true north is.
- Clues such as the visual layout of the land and the wind direction also help. Birds seem to have an innate knowledge of locations, routes and techniques to make these journeys.
Challenges & Threats
- Bad weather, exhaustion, predators and other natural obstacles.
- Stopover sites cleared for agriculture or industry.
- Pollution – trash, oil, chemical spills.
- Man-made structures such as glass buildings. Birds die when they crash into reflective windows.
- Other structures are giant wind turbines and power lines.
The East Asia-Australasian Flyway : the largest of five majoy flyways around the world, connecting 22 countries
- A flyway is the route taken by migratory birds, with a chain of stopovers in between.
- This particular flyway is one of the nine major migratory waterbird flyways, and it straddles 22 countries.
- 45% of the world’s population live within this belt.
- Over 50 million migratory birds – including 28 globally threatened species – use the East Asia-Australasian Flyway.
- The Arctic Terns’ annual round-trip from its Arctic breeding grounds to the Antarctic seas is 30,000 kms. They refuel en route by feeding at sea.
- The typical flying speed is 30 to 60 kmph and the typical altitudes are 3,000 to 8,000 metres – and this is day and night, over land and sea. The Bar-headed geese fly over the Himalayas at a height of 9,000 metres.
- A long-distance migratory bird would have covered 400,000 kms in 20 years of migration – about 10 times the mean circumference of the Earth.
- The tiny Ruby-throated Hummingbird, which weighs less than a 50 cent coin makes a 1,000 km, 24 hour spring flight across the Gulf of Mexico every year, from the Yucatán Peninsula to the southern coast of the United States.