Egrets have been dubbed "environmental friendly birds." Their presence is an indication of good air and water quality. They are under state protection at the second-class level.

With an improvement in Ningbo's environment in recent years, the egrets that had long since disappeared have now returned. Attracted by the now favorable environs of Ningbo University, the number of egrets resident on campus has increased sharply.

However, these beautiful birds have brought disruption and embarrassment to this normally quiet and refined campus through their droppings and noise.

In response, the University has set up loud bird-scares to disperse the egrets with a variety of frightening noises. The birds are indeed being both scared and dispersed but not without controversy.

The Green Environment Attracts Egrets and Trouble

With over 20,000 staff and students, Ningbo University is Ningbo's first key comprehensive university embracing a wide range of academic disciplines. Covering an area of 1,700 mu (282 acres), over 60 percent of the campus is covered by trees. There are thousands of lush green, dawn redwoods standing straight some 10 meters (33 feet) high. They are laid out to both east and west of the campus. Since the mid-1990s egrets and other birds have started to build nests and raise their young there.

During the three-year natural disaster (1959-1961), the egrets had disappeared from here due to deterioration in the local ecological environment. Thirty years later when the egrets returned, the University welcomed the arrival of these "honored guests" with great enthusiasm. They even set up a Bird Lovers' Association on campus in order to take good care of them.

However the good times did not last long once the egrets started to come in such swarms that they seemed to block out the sky. According to some junior female students, there were fewer egrets when they were in their first year. Then sitting in the classroom and looking out of the window, they really enjoyed watching the graceful flying figures of egrets in the woods. However, since more and more came last year, the roads have been painted white with bird droppings.

Everyday when they walk under the trees they run the risk of being "bombed" and have taken to sheltering under umbrellas on their way to class.

According to Teacher Liao from the administrative office, the birds' droppings have discolored the campus roads and made a mess in the woods. Many of the windows in the buildings nearest the woods are kept shut due to the revolting smell of droppings.

During April and May of last year when the egrets on campus reached their highest numbers, the dawn redwoods became a sea of white with birds' droppings everywhere. "Many teachers and students have asked us to find a way to deal with it," said Liao.

How to Disperse the Egrets?

Teacher Zhu also from the administrative office said, "Egrets are migratory birds which come here regularly in early spring and leave by the end of autumn. The number of egrets in Ningbo University reached a peak of about 20,000 last year. They will not leave of their own accord as they find this a good place to live and so their numbers have increased sharply.

"We finally took the decision to disperse the egrets because of the large area of dawn redwoods on campus that had actually died due to pollution by birds' droppings. A total of 370 dawn redwoods died last year within a short space of time.

"The school has spent in excess of 40,000 yuan (US$4,800) on digging ditches and replanting trees. These dawn redwoods have been growing here for more than 10 years. It really makes us sad to see them destroyed," he said.

How should they deal with the troubles brought by the egrets? According to Teacher Zhu, after considering many solutions they finally decided to disperse the egrets through modern technology, namely using artificially generated noises.

Teacher Zhu explained, "In order to carry out this plan, the administrative office has signed a contract with the Information Industry and Sci-tech Company of Ningbo University. The relevant researchers have developed a computer-based multimedia broadcasting control system. In developing this solution they consulted widely drawing on experience both at home and abroad from the Internet and from experts in the field.

"They have set up 24 "tweeters" in the dawn redwoods. Over a time cycle these broadcast a range of noises which include imitations of the sounds of fireworks and of the egrets' natural enemies. Few egrets are now seen and all that's left to remind us of them at their worst are the mottled droppings they have left in the woods and on the roads," he said.

Remaining numbers of egrets have been put at just 10 percent of the peak. The University has spent nearly 80, 000 yuan (US$9,600) to disperse egrets using these noises and has met with some success. According to Teacher Zhu, they are now in the process of fine-tuning the range of sounds used so as to find the most effective noises to disperse egrets.

However, broadcasting noises can only effect a temporary cure and cannot tackle the problem completely. The egrets will come back when the noises stop.

According to some students the reporter met outside the library, the noises being broadcasted every day not only scare the birds but also the students.

Criticism Following Dispersal

Although some staff and students at Ningbo University said they could well understand why the school is dispersing egrets using noises, many others have expressed different opinions and even strong opposition.

Teacher Wang from the Literature Institute has been studying and teaching in Ningbo University for 10 years. He said, "I have witnessed the boom in egrets on campus. They have become a symbol and a unique sight of the university. Many students have a strong affection for them. Although we all understand why the school has opted for dispersal, we still feel it hard to accept."

Ye Junhui, a student in the Life Science Department is one of those who strongly oppose the action of dispersing the birds. He said, "Egrets are migratory birds under state protection. Their numbers are depleted after they return here after living through the winter in the south. We are dispersing them at the time they are trying to raise their young and threatening their survival. To the egrets this is nothing short of a massacre. It may seem humane and benevolent to use noise alone to disperse the birds but actually it is very cruel to the egrets."

He describes seeing egrets lingering and uttering sad calls above the campus day and night since the school started to disperse them by broadcasting noises and letting off fireworks and feels the tragedy of their fate really moving.

As to how to solve the problems of their impact on the campus environment, Ye Junhui thought the school should consult more experts. It should find a better way to tackle this problem rationally by helping the egrets migrate rather than simply dispersing them.

A New Paradise for the Birds

Lai Yanxue, an expert in the Forestry Bureau, the department in charge of the bird protection, and senior engineer and second in charge at the Ningbo Forest Diseases and Insect Pests Prevention Station, gave his opinion on the controversy.

Lai Yanxue had been invited to participate in consultation on the death of dawn redwoods in Ningbo University in July of last year. In his view, the death of the dawn redwoods has been caused by multiple factors. Close planting has affected their access to light. There was heavier rainfall than usual during last year's rainy season and the roots are rotting because water accumulated in the low-lying parts of the woods. There was some damage due to seepage of polluted water. Finally the effect of birds' droppings cannot be excluded because the microbes and bacteria in birds' droppings can also damage the growth of the trees.

Lai Yanxue concludes that many internal and external causes have led to the death of dawn redwoods in Ningbo University, saying, "It is quite unfair to lay the blame only on the egrets."

Experts have pointed to measures taken by Ningbo University including disinfecting to kill the bacteria affecting dawn redwoods, digging drainage ditches together with a thinning out of the trees to improve ventilation and lighting. The situation in the woods has now clearly improved.

Turning to the question of whether the egrets on campus should be kept or dispersed, Lai Yanxue said, "First we should seek to understand why there are so many egrets on campus. Ningbo University is located by the banks of Yongjiang River with wide expanses of farmland all around. The egrets find their main sources of food like fish and shrimp in the river and farmland. However, only the campus of Ningbo University can offer them a large stretch of woodland in this area. Egrets are not solitary birds, they live in flocks, so more and more egrets are gathering together here."

"In fact, the woods are not the best habitat for egrets," said Lai Yanxue. "There used to be a large stretch of reeds on both sides of the Yongjiang River long ago. We call this wetland and it is actually the best habitat for egrets. It is a pity that such large stretches of reeds disappeared many years ago. If we really want to resolve the egret problem, we should first create an ecological environment suitable for their survival."

"It would not be at all difficult to plant some reeds and trees on the wet and fertile land of Ningbo. This could become a suitable wetland habitat in three to five years. As long as the environment nearby is improved and the egrets have a suitable place to live, they will not stay long in the narrow confines of the campus," he said.

Yuan Jin is second in charge at the Ningbo Forestry Bureau where he is responsible for wild animal protection. He says that they have been promoting the concept of the modern garden city in recent years. People living in harmony with nature is one of the important tenets of the garden city movement. Egrets have come here and could be good friends of humans.

"What should we do with them? Treat them well and try to live in harmony with them or just disperse them in order to avoid inconvenience? This is a new topic and challenge to be faced in the construction and management of our cities."

(新华网[Xinhua News Agency], translated by Wang Qian for china.org.cn, August 6, 2002)