Situ Zhiwen: Guangzhou Zoo – Black-necked Swan

Guangzhou Zoo (GuangZhou Zoo) is situated in Yuexiu District, Guangzhou. It is bordered by the 19th Route Army Cemetery to the east, Huanshi East Road to the south, Yunhe Road to the west, and Xianlie Middle Road to the north. There are two entrances, a south gate and a north gate, both with parking lots. The zoo opened in 1958 and covers an area of 42 hectares. In 2013, it received four million visitors.

Guangzhou Zoo is home to over 450 species (as of 2013) of mammals, reptiles, birds, and fish from across China and the world, with more than 4,500 individual animals. Many are rare and exotic. Among them, 35 species such as the giant panda, golden snub-nosed monkey, and black-necked crane are under first-class national protection, while 32 species including the red panda and white-naped crane are under second-class protection.

The zoo also doubles as a botanical display ground, with over 200 species of trees and more than 100,000 plants.

Its predecessor was Yonghan Park, established by the National Government in 1928 on Zhongshan 4th Road in Guangzhou, covering 2.2 hectares and exhibiting over 60 species with a total of more than 200 animals.

In 1950, Yonghan Park was renamed People's Park (now Guangzhou Children's Park).

In May 1955, it was officially named Guangzhou Zoo.

In July 1956, land around Mayinggang, off Xianlie Road, was requisitioned as the new site.

In October 1958, the new site was completed and opened to the public.

Since 2006, the zoo has been designated as a Guangzhou Science Education Base, a Guangdong Provincial Youth Science and Technology Education Base, and a National Youth Science and Technology Education Base.

In 2007, it was honored as an Advanced Unit for National Science Popularization Day in Guangzhou. In 2009, the municipal government proposed relocating the zoo to Maofeng Mountain, but the plan was shelved due to high costs and strong public opposition.

In August 2014, Guangzhou Zoo completed a design for upgrades, with a total investment of 81.53 million yuan.

At the center of Guangzhou Zoo, there are three lakes with fountains and small islands where animals live. Many free-ranging waterfowl swim freely on the lakes. Pavilions dot the lake shores, creating beautiful scenery.

The black-necked swan (Cygnus melancoryphus) is native to South America. Its posture is very similar to that of the whooper swan, and it is a rare bird. Males and females share very similar plumage, though the female is smaller. They measure 90–130 cm in length and weigh 3.5–4.4 kg, making them the world's smallest swan. Their body feathers are pure white like a whooper swan's, but their head and neck are black, making them distinctive and unique. On the forehead, there is a bright red fleshy knob, highly developed and striking. The cheeks are red, the bill is bluish-gray with a pale tip, and the legs and webbed feet are pink.

What is the most devoted animal in the world? When we speak of faithful, monogamous creatures, many think of mandarin ducks, which represent ideal love in folklore. However, mandarin ducks stay together only during the mating season; once that period ends, they seek new partners. In the animal kingdom, very few species remain with a single mate for life. The black-necked swan is one of the world's most loyal animals, strictly observing monogamy. Many swans would rather grow old alone than casually take a mate. Once paired, they are deeply devoted, always together — foraging, resting, splashing in the water, and never separating, even during migration. If one dies, the other will mourn day after day, growing depressed, and will choose loneliness over seeking a new companion.

They prefer freshwater or slightly brackish marshes, lakes, and lagoons with aquatic plants such as narrow-leaved cattails, banana grass, rushes, reeds, and duckweed. The black-necked swan is also the only swan species known to carry its young on its back while swimming. They breed in South America—Paraguay, Uruguay, Chile, Argentina, Tierra del Fuego, and the Falkland Islands—and migrate north in winter as far as Paraguay and southern Brazil near the Tropic of Capricorn.

Black-necked swans are extremely family-oriented. Both parents raise their young together. While all waterfowl guide their chicks alongside them in the water, only the black-necked swan carries its cygnets on its back, doting on them warmly.

Breeding starts in July each year, although if food is plentiful, it may begin as early as March or April. In captivity, individuals as young as two years old can pair and breed, but in the wild it happens later. The courtship display of black-necked swans is more intense than that of other swans, typically involving chasing rivals with lowered, outstretched necks. Once paired, the male and female live together, always side by side while foraging and moving about, and then seek a secluded spot to build a nest. Nest-building starts as early as July, with more southerly populations starting in September. The nest is usually built on reeds or small islands, using grass, twigs, and similar materials.

A clutch contains 4–8 cream-colored eggs, each weighing about 220 grams. The female incubates the eggs alone, while the male stands guard nearby. When the female leaves the nest to feed, the male may temporarily take over. Incubation lasts about 34–39 days. Occasionally, black-necked swans nest in colonies, but this leads to intense fighting due to limited food and nesting sites, resulting in reduced clutch sizes and lower breeding success.

The hatchlings are precocial and cared for by both parents. Since the adults spend nearly all day in the water, the cygnets ride on their parents' backs as they move around. Growth is slower than in other swans. Because their natural food is low in calories, many cygnets and juveniles die from malnutrition, bone deformities, or parasite infestations such as nematodes and flukes in the stomach. Juvenile plumage is brownish-gray; after a year, they acquire adult feather coloring but remain smaller and lack the red forehead knob. Black-necked swans reach sexual maturity at 3–4 years and live 25–35 years.

With a wide distribution range and stable population trends, the species does not meet the vulnerable or threatened criteria (range less than 20,000 km², habitat quality decline, fragmented distribution) and is therefore assessed as not facing a survival crisis.

Listed as Least Concern (LC) on the IUCN Red List ver 3.1 (2012).

Listed in Appendix II of CITES.

Newly hatched black-necked swan cygnets have down that is gray or white depending on variety, similar to domestic goslings. They can feed themselves and may be raised by parents or by hand using a temperature-controlled box. Usually, after two weeks they are moved indoors with a floor covered in fine sand and a layer of straw, kept warm with an electric lamp or brooder. The temperature should be 31–34°C in the first week, 28–30°C in the second, 24–27°C in the third, and thereafter maintained at 18–21°C.

The cygnets' diet consists of steamed mixed grain buns, eggs, fresh greens, bone meal, calcium powder, cod-liver oil, vitamins, and trace elements. In the early brood stage, with high ambient temperatures and food that spoils easily, feeding should be frequent—four times daily. As the cygnets grow and the environment cools, feeding frequency is gradually reduced.

When hand-rearing cygnets, attention must be paid to hygiene as well as temperature and diet. Because swan feed is soft and they often fling it while eating, their down and bedding easily become soiled, so bedding must be changed frequently. When the temperature is suitable, let the cygnets bathe once or twice a day, but always supervise to prevent drowning. Bathing and swimming sessions can be gradually extended from half an hour to one hour, based on the cygnets' condition and ability. Ensure they get plenty of sunlight and exercise. After a month of careful care, the cygnets will grow up healthy.

Their feed is divided into grains, mash, and green forage. Grains include corn, sorghum, rice, or paddy, which are staple feeds. Mash is a mix of barley meal, corn meal, sorghum meal, soybean cake meal, bran, fishmeal (or silkworm pupa meal), bone meal, salt, and various vitamins and minerals, mixed with water and fed moist (or steamed into buns or pressed into pellets). Green forage includes all kinds of leafy vegetables, waterweeds, and grasses.

Mash is given once or twice daily in winter. Grains should be available frequently, topped up little and often. In summer, large amounts of green forage are fed, either chopped and mixed into the compound feed or thrown into the water for them to eat freely. In winter, supplement with appropriate vitamins.

In daily management, for swans kept in flocks, control feed quality and quantity, and keep food and water containers and the environment clean. For pairs, clean the enclosure daily, observe their feeding, droppings, and behavior, and watch for any unusual changes.

Spring: In mixed flocks, watch for fighting and intervene immediately if it occurs. Prepare nest boxes in advance for breeding. Increase the protein content of feed during the breeding season.

Summer: Feed as much green forage as possible. For flocks, pay attention to feed and utensil hygiene, and keep water clean. Change drinking water frequently.

Autumn and Winter: Although swans native to northern China are cold-resistant, take steps to prevent frostbite on their feet. Maintain a partially frozen water surface, spread thick straw bedding on the ground, and add windbreaks and heating.

They mainly live on water, swimming with gracefully curved necks and heads held low. In flight, the neck extends forward and legs trail behind, with slow, powerful wingbeats. Their diet consists primarily of various aquatic plants, seaweeds, algae, and a small number of aquatic insects, fish eggs, and crustaceans; in some areas they specialize in a single waterweed. They usually forage in open, shallow water, continuously dipping their head and neck into the water to take food from the surface layer, but they rarely upend in the water.

Black-necked swans are timid and highly alert. When startled, they call and flap their wings as they take flight from the water. Normally, their calls are very soft, sounding like a panting noise, and do not carry far. In the wild, the crested caracara is their main predator, often preying on cygnets, juveniles, or eggs in the nest.

They like to gather in flocks, sometimes mixing with other waterfowl such as coscoroba swans, but the flocks are usually not large. Against the deep blue sky, they alternately spread their wings, soar and circle, or dive like arrows to the water with incredible lightness. When floating quietly on the lake, they appear ethereal, leisurely, and varied in posture, like a painting brought to life — a sight that captivates the eye and stirs the soul. Outside the breeding season and during dry spells, thousands of black-necked swans may flock together, often squabbling among themselves. When drought or excessively high water levels occur, they may disperse and fly some distance.

Photographed by Situ Zhiwen for Jinmenwang