In May 2018, the 16th Swift Ring of the Summer Palace, Fu Jianping (left) and Zhao Xinru (right), the on-site technical commander, determined the workflow.
Photo by Gao Jingxin
Volunteer Bai Tao opened a 2.4MB (megabyte) picture on his computer. The picture showed a gloomy sky and a corner of an ancient building.
He rolled the mouse, and the photo was continuously enlarged. Some dense black spots in the sky gradually became clear and took shape, and "changed" into a pair of scythe-shaped wings.
"There are not many Beijing Swifts on this picture, more than 70."
A few days ago, Swift Huanzhi volunteer Fu Jianping received a call from an old gentleman.
The bird friend is very old and does not usually go out. She saw the news of "the first accurate reveal of the migration pattern of swifts in Beijing". She was very emotional during the call and was proud of the role of the volunteers in the research.
"A group of volunteers from the China Bird Watching Society have become the backbone of well-trained banding. In the banding work of wearing locators for Beijing Swift, they have shown the power and literacy of citizens' participation in science." Fu Jianping said.
The survey and research conducted by the public are clearly depicting the number and migration patterns of Beijing swifts, laying the foundation for the next step of protection.
1 "Count" swifts and find out the bottom line
In order to find out the distribution of swifts in Beijing and protect the swift population in the Beijing area, in 2017, Beijing Wildlife Rescue Center and Xuanwu Youth Science and Technology Museum launched the Beijing Swift Survey Project to conduct surveys in 30 locations where swifts are distributed. Society recruits volunteers.
This spring, Bai Tao joined the volunteer team.
Every two weeks, he makes a special trip to the Wulong Pavilion in Beihai Park to record the number of swifts in Beijing.
At dusk, swifts often fly in groups. At this time, Bai Tao will raise his mobile phone towards the White Pagoda on Qionghua Island and take a photo of the sky due west, directly above his head, and due east.
"Three pictures are a group. I want to record the time and shoot more than ten groups." I chose to take pictures and records at this time, because the number of Swift clusters is relatively concentrated, which is convenient for accurate statistics.
Bai Tao is a bird watcher, and there are many high-definition pictures of birds in the SLR camera.
Photos of the sky full of "little black dots" are not aesthetically pleasing to him.
But they are the basis for investigating swift numbers.
After returning home, Bai Tao would count the "black dots" on the computer screen.
In order to count more accurately and quickly, volunteers usually set the picture as the background of the excel sheet, mark the number of swifts in each cell in the excel sheet, and then use the summation tool to calculate, and then record the time and quantity of the photo to the survey platform.
Counting swifts, though tedious, is the last part of a scientific investigation, he said.
The number of Beijing Swifts once decreased, but in recent years, they have frequently returned to people's sight.
"But how many and where they are distributed is still unknown."
2 During the observation, once rescued the drowning swift
On the evening of June 17, Bai Tao, who had completed the swift observation, was about to leave when an object floating in the water caught his attention.
"It's a bit like a dry leaf. I looked closely and found it was a swift." The swift showed no signs of struggling, and it didn't look very good.
Bai Tao hurriedly went to the nearby bathroom to find the copy net and salvaged the swift.
The swift was soaked all over, but still had body temperature, and the ups and downs of its chest and abdomen indicated that it was still breathing.
"But it's a little nervous, and its claws hang tightly on the net." Bai Tao took the swift off the net according to the method he had learned before.
Since there was no cardboard box at the time, Bai Tao kept drying its wet feathers with paper towels according to the method taught by the staff of the Beijing Wildlife Rescue Center.
"I also covered it with a tissue to make sure its vision was dark, so that it would not be disturbed or frightened by the surrounding noise as much as possible." Swift hung on Bai Tao's clothes, and he sat quietly with Swift until the sun set. .
Near 8 o'clock in the evening, the recovered Swift climbed up, and when it reached Bai Tao's neck, it tried to spread its wings and flapped its wings and flew away.
According to Shi Yang, a senior engineer at the Beijing Wildlife Rescue Center, the 2021 Swift Scientific Survey will be carried out at 30 survey sites in the urban area of Beijing, with 196 volunteers participating in the survey for more than four months.
In the 30 survey points, the maximum number of swifts is 9,060. It is estimated that the total size of swifts in the 30 survey points can reach about 10,000.
3 The backbone of bird ringing, laying the foundation for swift research
Recently, a tracking study on the migration behavior of Beijing swifts was officially published in the international journal "Movement Ecology", which for the first time accurately revealed the migration ecology of Beijing swifts.
There are also volunteer contributions behind this research.
In 1998, Fu Jianping, who likes bird watching, first came into contact with Huanzhi.
Bird ringing is an important means to study the migratory dynamics and laws of migratory birds. Generally, a metal bird ring is worn on the tarsus (foot) of the bird.
The logo ring is like an ID card with a unique number. When it is recycled, the finder can check the relevant information of the wearing bird and report the location and date of the bird to the ring sign agency. , and upload it to the data sharing platform of Huanzhi.
"In many foreign countries, the ring is done by volunteers." Fu Jianping said.
During the May 1st and 11th holidays every year, friends around her go to the scenic spot to enjoy the mountains and waters, while Fu Jianping "unmoved" to Beidaihe, where there is a bird ringing station. Participate in the ring.
"Banding is a very hard job." Fu Jianping said, to ring a bird, you must first lay a net to catch the bird.
Early morning and dusk are the two most active periods for birds, and the "surfing rate" is the highest at this time.
Therefore, before dawn, the volunteers will set off and arrive at the net field in the rice field to wait.
At dawn, volunteers quickly rescued the birds that had crashed into the net.
In the morning and afternoon, volunteers also patrol the huge net field every two hours to prevent some birds from hanging on the net for too long and dying due to lack of water and exposure to the sun.
Ringing is also a technical job that practice makes perfect.
Fu Jianping still remembered the feeling of holding a bird in his hand for the first time.
Over the years, the volunteer partners who persisted with her have become the backbone of the bird ring.
In the process of wearing the band, if you do not operate properly, your fingers may be cut.
But the volunteers are skilled and the strength is appropriate.
"If there's not as much 'confrontation', they can relax."
4 Put on a "small school bag" for Swift
Wear a logo ring for Beijing swifts, weigh them, measure beak length, tarsus length, body length, wing length, tail length, and let them fly... In the Summer Palace Kuoru Pavilion, such Beijing swift ringing activities have continued for many years (stopped during the epidemic).
From this, people continue to refresh their cognition of Swift.
The Kuoru Pavilion of the Summer Palace attracts a large number of swifts to build their nests and breed here every year.
Since 1997, Gao Wu, a teacher from Capital Normal University, has led students to conduct an internship in Beijing Swift Swallow Ring Recording in Kuoruting. After 2002, the ring ring activity has been suspended.
Beginning in 2007, the China Bird Watching Association once again launched Beijing Swift Rings in Kuoruting.
"Five years later, we are looking forward to recapture and recycling." Fu Jianping said that in 2007, a total of 40 Beijing swifts were caught, of which 1 was the swift that had been recorded in 1998.
Recycling information shows that Beijing Swift can live for at least 10 years.
Over the next 5 years, the ringing work improved the net capture strategy and technology, and the recovery rate of swifts continued to rise.
By 2012, the recycling rate was as high as 53%.
"The high recovery rate tells us that the Beijing Swift is very loyal to the original breeding ground. One individual who was ringed in 2000 was recovered, indicating that the Swift was at least 13 years old. This is the result of our continuous ringing."
In 2014, the international cooperation on the tracking research of Beijing Swifts was launched, and researchers wore photosensitive locators for Beijing Swifts to study their migration patterns.
Fu Jianping said that swifts have four toes facing forward, so they cannot grasp, and they cannot pedal and take off after landing. Therefore, they spend most of their life flying, and even mating and predation are carried out in the air, so when they are not in the breeding grounds, they will Unable to be captured and log migration information through the ring.
The locator can relatively accurately describe the migration path of Beijing swifts.
When wearing the locator, volunteer Liang Xuan gently but firmly held the Beijing Swift and helped the foreign experts carry this "little schoolbag" on their backs.
When the expert puts the noose on the bird's wing root, Liang Xuan will carefully loosen one side of the swift's wing.
In order to verify whether the tightness is appropriate, the two will use a pencil to pass through the rope under the back of the swift. If it can pass through, it means it is just right. In this way, there is a gap between the positioner and the back of the swift, and the rope will not. The streak is so tight that it affects the flight of the bird.
The feathers of the bird are fluffy, and after combing the feathers, the small locator is hidden under the feathers of the Beijing Swift.
"Good job." Liang Xuan's skillful technique and standard posture won the appreciation of experts.
Before 2015, the migration route of Beijing Swift was unknown.
Some speculate that after leaving Beijing, they will fly over the Himalayas to the Indian subcontinent, while others believe they have flown along China's eastern coast to Southeast Asia.
That year, when Beijing Swift flew back to the Summer Palace again, the researchers recovered the first batch of equipment.
Everyone was surprised to find that Beijing Swifts experienced an epic flight to Southwest Africa.
"The moment the data was read out, the volunteers at Huanzhi were very excited, and everyone felt that they had done something very meaningful." Fu Jianping still couldn't hide his pride when he recalled the scene seven years ago.
Liang Xuan's job is a teaching and researcher. She admits that when she first started doing bird ringing, she found it fun and interesting, but after persevering, she will find that it is difficult and boring.
Unlike bird watching, which can go to different places and see various interesting behaviors of birds, ringing needs to repeat the same work at a fixed location, catching birds, looping, measuring, releasing... However, the study of bird migration patterns A large amount of data is needed to accumulate, and the probability of researchers and volunteers recapturing the Beijing Swift that has been recorded is not high.
This also means that more Beijing Swifts need to be banded, and more people need to be involved in the work of bird banding.
"Understanding the migration of Beijing swifts is a prerequisite for their protection. More people are welcome to join us and protect Beijing swifts together," said Liang Xuan.
Beijing News reporter Zhang Lu