Bringing a new lease of life to city wetland areas

There's an old saying in China: men die for fortune, birds die for food.

They arrive, often exhausted, at city wintering grounds, unsure of what they will — or won’t — find.

Habitat destruction and water pollution may have wiped out their food supply from the previous year, leaving them having to fly on hungry or face a grim fate.

How vulnerable species are to habitat loss is illustrated by the sad story of Shanghai’s tundra swans, which migrate down from Siberia and the Arctic.

In the 1980s, Dongtan wetland on Chongming Island was home to the largest flock of wintering tundra swans in China, estimated at more than 3,000.

But after a major land reclamation project in the early 1990s, the numbers crashed to almost zero.

The reason was simple. Tideland was enclosed for cultivation, depriving the tundra swans of their grassweed food source — an aquatic plant common in wetlands. Without a suitable habitat, the birds had to look elsewhere.

In recent years, as the wetlands within national conservation areas have become protected, plantlife is returning, as are some tundra swans.

Numbers are increasing, but it’s still only a small fraction compared to previous times.

Ducks, geese and swans make up the bulk of migratory birds that winter in Shanghai every year.

Inshore mudflats, rivers and lakeland areas are ideal habitats, but as land pressure outside of reserves sees such areas turned into farmland, the birds are squeezed out.

Most migrants arrive from the Arctic, Siberia and northern China. After the breeding season in the north, the adult birds take the juveniles and embark on the long trip to the middle and lower Yangtze River, stopping off at Shanghai.

Many of Shanghai’s migrants have their own niches, ensuring there is not too much friction with other species.

The ducks are omnivorous, with food mainly consisting of water plants and aquatic creatures.

Shanghai’s swans and geese, on the other hand, are predominantly herbivores.

They mainly inhabit in inshore areas in Chongming Dongtan, Jiuduansha in Pudong New Area and Nanhui Dongtan, and feed on tender leaf buds.

As well as habitat loss and pollution, Shanghai’s ducks, geese and swans also still have to contend with some poaching, even though officials say the problem is less widespread that before.

Battling the illegal poaching

To protect wildlife in Shanghai — not just birds, but everything from rabbits to frogs — the city created its first wildlife reserve in Nanhui Dongtan — covering an area of 122.5 square kilometers north of the Luchao Port ferry terminal in the Pudong new Area — in 2007, followed by another in Fengxian District in 2013.

The reserves are backed by legislation that makes it a criminal offence to capture or kill creatures that live there.

Anyone caught with more than 20 animals faces criminal charges. The severity of the charges increases according to the number of animals involved.

Gu Jianming, law enforcement division chief at the Pudong New Area wildlife protection station, has been working in the district since 1997.

Among the responsibilities of Gu and his four-strong team is investigating poaching.

“If we capture poachers at the scene, no matter the number of animals they’ve hunted, we hand them over to the police,” Gu said.

The law enforcement has to catch them on the scene with evidence in hand.

“We caught poachers who had caught four Chinese hares using electric nets,” he said.

“There are also people who report cases to us. We follow the leads to investigate,” Gu explained.

Live wildlife found with poachers is set free. Animals that are dead are buried, added Gu.

The team’s work follows seasonal cycles. In winter, when ducks, geese and swans arrive in large numbers, the team steps up patrols at wetlands.

In October when other migratory birds arrive, they pay more attention to the woodland those species favor.

And in March and April when the waders come, they focus more on the mudflats.

“A few years back there were more poachers hunting waders, ducks, geese and swans but as we’ve increased patrols and law enforcement efforts, we have few wildlife poaching cases in Dongtan now,” Gu said.

Gu said that occasionally poachers will turn violent when confronted, but that this is very rare.

“Sometimes they’re rude, using strong language, but we’re reasonable and explain to them,” he said.

“Usually they’ll understand these animals cannot be captured,” he said.

As we near the end of March and most migratory birds have left to fly north, it’s difficult to find any ducks, geese and swans in Shanghai.

But when they return this winter, Dishui Lake in the southeast corner of Pudong is a good place to see ducks and geese as well as other species such as Eurasian coots.

Facts you may not know

Though birdwatching has only been a popular pastime in Shanghai for a decade, many previously undocumented species have been spotted — such as Baer’s pochard, the scaly-sided merganser and the whooper swan.

Surprises come all the time, and these “VIPs” may just be looking at you as you walk by, say city birdwatchers.

• 2008: During an inshore bird survey in Fengxian, an investigator spotted a scaly-sided merganser — a species so rare now that it’s called “panda in water.”
  
• 2010: A birder spotted a very rare ferruginous duck among a flock of ducks in Dongtan Wetland Park.
  
• 2011: In a first in Shanghai, two twitchers spotted a black scoter (also called American scoter) on the Paotaiwan wetland park while observing herring gulls.
  

Get to know some feathered friends

Ducks, geese and swans belong to the family Anatidae, and an average of 70,000 birds from this family fly to Shanghai to overwinter, according to synchronized aquatic bird survey statistics issued by Shanghai Wildlife Conservation Association in recent years.

A total of 33 species from this family have been documented in Shanghai in the past decade, with the spot-billed duck, common teal and mallard ranking the top three in population.

Usually arriving in October and leaving in March, the birds have their own preferred habitats, concentrated in Chongming Island, Nanhui Dongtan and the coastal area.

Tundra Swan

The tundra swan is about 120 to 150 centimeters in length and weighs between 3.4 to 7.8 kilograms.

The adult swans have white plumage and black feet, while the immature birds are light-gray feathered until their second winter. The bill is mostly black, but has yellow spots at the base.

The sound whistling swans make is similar to whooper swans but in higher pitches. A flock singing together produces sound like “klah.”

A migratory species that breeds in the Arctic and subarctic tundra, it travels to wintering habitat near the coast. The tundra swan is not globally threatened, but the population in Shanghai suffered a significant decline in the last century.

Mallard

The mallard is the ancestor of nearly all domestic duck breeds and is widespread around the world.

The female mallard makes a quacking sound, while the males have a quieter, rasping sound. Like all ducks, they shed their flight feathers at the end of the breeding season and are flightless for three to four weeks.

The average length for both sexes is 50 to 65 centimeters, and they weigh 0.75 to 1.5 kilograms.

The mallard’s diet is omnivorous and opportunistic. They eat seeds, aquatic and terrestrial plants, as well as invertebrates such as insects and crustaceans.

Spot-billed duck

As one of the most common duck species found in China, the spot-billed duck is found in fresh water and feeds mostly on plants.

A large, stocky dabbling duck, the bird got the name for its yellow-colored bill tip.

Usually 58-63 centimeters in length and weighs 0.75 to 1.5 kilograms, the adult’s plumage is dark and brown, and the legs and feet are bright orange.

The drake and hen look similar, although the female’s plumage is lighter.

According to “Birds of East Asia” by Mark Brazil, the spot-billed duck’s call is similar to a mallard, but stronger.

Common teal

Also called the Eurasian teal, it’s a small migratory dabbling duck with an average length of 20 to 30 centimeters and weighs around 350 grams.

Their legs are short but strong, and the drake’s bill is darker than that of the hen and juveniles.

The male common teal is slightly larger than the female, and the breeding plumage color also differs. The drake’s head and upper neck is chestnut, with a dark green area surrounding the eyes, and he has wide white wing stripes. The hen’s is brownish with a darker back and wings. Outside of the breeding season, the sexes look alike.

It’s a species of northern Europe and Asia, usually fly in large flocks, and nest on the ground. Their diet includes molluscs, worms and insects, as well as seeds of aquatic plants, grasses and grain.