The common sandpiper (Actitis hypoleucos), harbinger of a fall season of migratory birds, flies from north to south every fall, and the Kuantu area is its midway stop.
In the outskirts of Taipei, flanked by mountains to the northeast and tableland to the southwest, at Kuantu, the Chilung River merges with the Tamsui River. At this converging point, the Tamsui expands its waterway, and its velocity slows down. A large amount of fresh water mollusks are brought down from upstream and precipitated here.
Kuantu is also the high point of sea flow during high tides, which bring in large amounts of sediment, immature oysters, worms, and the like. Kuantu's multiple sources contribute ample foods for its birds.
The mountains to the northeast screen the area from the cold northeast seasonal winds. Kuantu, full of marshes, sand beaches, tall grasses, paddy fields, and wastelands, provides fine shelter for the migrants.
Those migrant birds of the northern hemisphere that procreate in the summer in the Arctic and Siberia, in the autumn take one of two major routes south: via the Kamchatka Peninsula, along Japan, the Ryukyus, Taiwan, and the Philippines, to Indonesia or Australia for the summer; or along the east coast of the Asian Continent, through the Taiwan Strait to equatorial lands. In spring, they may follow the same routes back. Taiwan stands at the intersection of the two routes.
Most of the migratory birds reaching Taiwan are transients, who take a rest and refreshments along the Tamsui River and then go on. Some are winter visitors who stay till the next spring, then join the team for home. The Tamsui River, specifically at Kuantu, is the most popular of bird resorts in northern Taiwan.
There are other spots in Taiwan, where birds concentrate, but Kuantu is unique. Tsai Hong-ye, the former president of the Taipei Wild Bird Society, who has observed the birds in Kuantu for 10 years, points out that Kuantu is the most northerly major stop for migratory birds on the island. Further south are the Lan-yan Plain of east Taiwan, and the banks of the Datu River in central Taiwan. But Kuantu offers the first views of the yearly autumn migrations.
According to Tsai, 171 bird species have been recorded at Kuantu—43 percent of the 400-odd species of birds appearing in Taiwan as recorded in Birds of Taiwan (1981).
The yearly peak of their arrival frequency usually occurs from April till May, when birds congregate here on their way home. From August till December is the second peak, when birds come in scattered legions.
Kuantu harbors a microcosm of northern Asian bird species, its various habitats hosting about nine major bird families. Snipes and plovers account for the largest numbers of bird types. From August till December, Kuantu's swarms of birds echo each other's voices, hunt food, and are "hunted" by large groups of bird watchers through all manner of telescopes and other optical instruments.
Common sandpipers and little-ringed plovers (Charadrius dubius) always arrive early, pathfinding for the horde. This year, common snipes (Capella gallinago) and greenshanks (Tringa nebularia) followed directly.
Common sandpipers always come in small groups, in a constant numbers buildup that makes them the mast frequently seen bird from the beginning of the season till early November.
An experienced observer, Liu Ke-hsiang, divided the seasonal span into three highlights for certain groups of birds. The first is the Pratincoles (Glareola maldivarum) Period from late August till mid-October. The second, the Common Sandpiper Period, ending in early November. And last, the Dunlin (Calidris alpina) Period, usually till early January.
Tsai noted that sometimes the periods are indistinct. But, generally speaking, the pratincoles, meadow birds, usually come in hundreds in September and October, stopping in Kuantu only a few brief days. The dunlins usually come in the thousands in November. The common sandpiper is usually both the "firstcomer" and almost the "lastgoer."
The eastern pratincoles, whether resting on dry paddy fields, hovering against the sky, or chirping songs over the dikes, are dramatic with their white bodies, olive-brown backs, long pointed wings, and deeply forked black tails.
Every year here, the golden snipes (Pluvialis dominica) are also showstoppers. The snipes are bold, coming close to human audiences. Small birds, like the Kentish plovers (Charadrius alexandrinus) and common sandpipers, and large birds, like the wood sandpipers (Tringa glareola), mass in the blue skies, showing off their beautifully-figured flight maneuvers.
When the eastern pratincoles leave the scene, it is time for the winter migrants. With only several golden snipes left, the sandpipers are near lonely until joined by small groups of herons and egrets.
In November, the streaked brownish-gray dunlins arrive. Their bills are noticeably downcurved at the tips, and they move and eat in perfect teamwork. They mark the stage in which birds arrive in great hordes.
Along the river banks, three other congregating spots are easily accessible to bird watchers. First, within the estuary of the Tamsui River, is a convex beach; next is a large patch of Kandelis Candles mangrove at a place called Chuwei, and the third is under the Chunghsing Bridge along spotty grass and mud banks. Tracing the Tamsui River upstream, the estuary is the first spot, followed by Chuwei, Kuantu, and the Chunghsing Bridge. The four offer specific habitats for many varieties of birds.
Along the northern edge of the estuary, Kentish and Mongolian plovers appear in large amounts, joined by golden plovers. The plovers, thick-necked with short and thick bills, usually come in swarms, sometimes alone; they can be seen scurrying along beaches or flipping over pebbles and shells. The Kentish plovers here are nestlings, the only birds of the group that make Taiwan their breeding place. The reason there are so many plovers here, experts explain, is that both the Mongolian plover and Kentish plover can stand the cold winds of the island's semi-tropic winter, and they thrive on sandy beaches and beach dunes. Some blue rock thrushes (Monticola solitaria) join them, breaking up the monotonous (to bird watchers) uniformity of the plovers.
In the thick mangrove at Chuwei, little egrets (Egretta garzetta), black-crowned night herons (Nycticorax nycticorax), and cattle egrets (Bubulcus ibis) hide away. The area is a resort for herons and egrets, long necked, long legged, and long billed—birds with a proud walk and a resting habit of standing on one foot. They are winter sojourners, staying from August clear to April.
Under the Chunghsing Bridge, ducks dominate the scene. They float on the shallow waters, then suddenly diving, shatter their colorful reflections. The northern shoveler (Anas clypeata), with green-glossed head and neck, white breast, and chestnut belly, usually appears in large flocks.
Kuantu, however, provides the most colorful autumn show. Some very special birds have been spotted: the black-winged stilt (Himantopus himantopus), Australian curlew (Numenius madagascariensis), and pheasant-tailed jacana (Hydrophasianus chirurgus) are the most famous. The stilts, from Mongolia, flash sharply contrasting black-white feathers and pink legs. Their thin figures are very graceful, their walks elegant. Australian curlews do not frequent Taiwan. These rare transients come from the Sea of Okhotsk and the Kamchatka Peninsula and do not stay long. The pheasant-tailed jacana is a very special indigenous breed. The jacana is not a pheasant, but has a long, curved tail like a pheasant, and is also famous for its colorful feathers. Recently, a rare penduline tit was spotted. According to the bird society, about 10 to 20 additional species are listed every year.
Each year as more bird watchers gather at Kuantu, more species are recorded. But an English biologist, Swinhoe, gets the credit for first documenting the birds of Taiwan; he first came here around 1856, when he traced the Tamsui River and ranged the mountains. To the Japanese goes the credit of recording most species. Japanese bird watchers and scholars come to Taiwan especially to connect and compare the species here with those in Japan.
Recently, there has been great interest and movement in wildlife conservation and nature preservation on Taiwan, reflected in the designation of government-protected bird sanctuaries at Kuantu and at the Chunghsing Bridge.
The Taipei City implementing regulations allow no unapproved changes in the geological natures of banks, sand beaches, and marshes; no dumps or waste disposal; no digging of sand or mud; no hunting, trapping, or netting unless specifically stipulated; no collecting of the mollusks, shells, and worms.
The city plans to set up explanatory boards, public telescopes, etc. in the two areas.
Taipei's action has heartened the Taichung Wild Bird Society, which has been pushing for sanctuaries in the mountains, where most of the rarest local species make their homes.
But there is also bad news. Tsai says that in early spring this year, the northbound birds decreased both in species and numbers. He cited the dumping of dirt over marshes close to one dike here, and water pollution both here and in other host countries as ruining habitats and reducing food.
Taiwan is listed among 111 locations in the world where birds may be specially enjoyed, in the book Finding Birds Around the World, published in 1981, and it is now taking steps to assure its place.
Lee Chin-hsing, president of the Taipei Wild Bird Society, noting that a meeting on East Asian birds is scheduled this month in Taipei, indicates that the local movements intend to join in aggressive international efforts to protect birds.