Volunteer Bai Tao opened a 2.4MB picture on his computer, showing a gloomy sky and a corner of the eaves of an ancient building. He scrolled the mouse, the photograph was constantly enlarged, and some dense black dots in the sky gradually became clear and took shape, "changing" a pair of wings in the shape of a sickle. "The Beijing Swift on this map is not much, more than 70."
A few days ago, Fu Jianping, a volunteer at Swift Huanzhi, received a call from an elderly man. The bird friend, who is old and usually does not go out, saw the news that "the migration law of Beijing swifts is accurately revealed for the first time", and was very emotional during the call, proud of the role played by the volunteers in the research.
"A group of volunteers from the China Bird Watching Society have become well-trained backbones of Huanzhi, and in the Huanzhi work of wearing locators for Beijing Swift, they have demonstrated the strength and literacy of citizens to participate in science." Fu Jianping said.
Public participation in the investigation and research is clearly depicting the number and migration of Beijing swifts, laying the foundation for the next step of protection.
"Count" swifts and find out the bottom number
In order to find out the distribution of Beijing swifts and protect the swift population in Beijing, in 2017, the Beijing Wildlife Rescue Center and Xuanwu Youth Science and Technology Museum launched the Beijing Swift Survey Project, conducting surveys in 30 locations with swift distribution and recruiting volunteers for the community. This spring, Bai Tao joined the volunteer team.
Every two weeks, he made at least one trip to the Wulong Pavilion in Beihai Park to record the number of Beijing swifts. At dusk, swifts often fly in groups, at which point Bai Tao will raise his mobile phone towards the White Tower on Qionghua Island and take a picture of the sky due west, directly above his head, and directly east. "Three photos are a group, I want to record the time, shoot more than 10 sets." Choose to take photos at this time, but also because the number of swifts is relatively concentrated after the cluster, it is convenient to accurately count the number.
Volunteers Bai Tao (left) and Beibei (right) observe swifts at Wulong Pavilion, Beihai Park, July 11. Bai Tao took a photo with his mobile phone and counted the number of swifts. Beijing News reporter Xue Jun photographed
Bai Tao is a bird watcher, and there is no shortage of high-definition large pictures of birds in the SLR camera. The photos of the sky covered with "little black spots" are not aesthetically pleasing to him. But they are the basis for investigating swift numbers.
When he got home, he counted 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 table, mark the number of swifts in each cell in the excel table, and then use the summing tool to calculate, and then record the time and number of photos taken to the survey platform. Because this work is very trivial and requires care, Bai Tao likes to choose a relatively complete time to carry out. "If you're counting and getting disturbed, you might have to start over." He said that counting swifts, although boring, is the last link in the scientific investigation work, and the final number presented makes the whole work form a closed loop.
Bai Tao liked the Beijing Swifts when he was young and thought they were particularly beautiful. The number of Beijing swifts once declined, but in recent years they have frequently returned to people's vision. "But exactly how many of them there are and where they are distributed is still unknown." He believes that such scientific investigations require the participation of more public forces, which is also part of the public protection of Beijing Swift.
In Beihai Park, volunteer Beibei wears t-shirts emblazoned with the words "Ordinary Swift". Beijing News reporter Xue Jun photographed
During the observation, he rescued the falling swift
On the evening of June 17, Bai Tao, who had completed his swift observations, was preparing to leave when an object floating in the water caught his attention. "It's a bit like a dry leaf, but when I looked closely, I realized it was a Beijing swift." Swift showed no signs of struggling and didn't look very well. Previous veteran volunteers had told him that due to the water near the Beihai Wulong Pavilion, the Swift Survey Beihai Observation Group had specially prepared a net.
Bai Tao quickly went to the nearby bathroom to find the copy net and salvaged the swift. The swift was soaking wet, but it still had body temperature, and the rise and fall of its chest and abdomen indicated that it was still breathing. "But it's a little nervous, and its paws are hanging tightly on the copy net." Bai Tao followed the Baoding method he had learned before and plucked the swift from the Net.
Since there were no cardboard boxes at the time, Bai Tao kept drying its wet feathers with a tissue according to the method taught to him by the staff of the Beijing Wildlife Rescue Center. "I also covered it with a tissue to make sure its line of sight was dark, so that it was as uncontasctioned and frightened as possible by the noise around it."
Swift hung on Bai Tao's clothes, and he sat quietly with Swift until the sun set. At nearly 8 o'clock in the evening, the rejuvenated Swift climbed upwards, and when it climbed to Bai Tao's neck, it tried to spread its wings and flapped its wings and flew away. At this time, the Five Dragon Pavilion turned on the night lighting, and the swift circled around the gorgeous ancient building several times and disappeared into the night.
According to Shi Yang, senior engineer of Beijing Wildlife Rescue Center, the 2021 Swift Scientific Survey was carried out at 30 survey sites in Beijing, and 196 volunteers participated in the survey for more than four months. Among the 30 survey sites, the maximum number of swifts is 9060, and it is speculated that the total size of swifts in 30 survey sites can reach about 10,000.
The backbone of bird rings, laying the foundation for swift research
Recently, a research study on the tracking of the migration behavior of Beijing Swift was officially published in the international journal "Movement Ecology", which accurately revealed the migration ecology of Beijing Swift for the first time. Behind this research, there are also volunteer contributions.
In 1998, Fu Jianping, who likes bird watching, first came into contact with Huanzhi.
Bird rings are an important means to study the migration dynamics and laws of migratory birds, generally wearing metal bird rings on the tarsal parts (feet) of birds. The logo ring is like an ID card, with a unique number, when it is recycled, the finder can consult the relevant information of the bird worn, and report the location, date and other information of the bird to the huanzhi agency and upload it to the huanzhi data sharing platform. "The feasibility of public participation in Huanzhi is great, and in many foreign countries, Huanzhi is done by volunteers." Fu Jianping said.
Every year during the May Day and Eleventh holidays, friends around her go to scenic spots to play in the mountains, and Fu Jianping "thunders" to Beidaihe, where there is a bird ring station, where she and other volunteers receive training and participate in huanzhi under the leadership of professional teachers.
The 16th Swift Ring of the Summer Palace, Fu Jianping and Zhao Xinru, the on-site technical commander, determined the workflow. Photo by Gao Jingxin
"Rings is a very hard job." Fu Jianping said that to give the bird Huanzhi, he must first lay a net to catch the bird. Early morning and dusk are the two most active periods of the day, when "internet access" is the highest. So before dawn, the volunteers had to leave for the netting in the rice paddies. At the dawn of the morning, volunteers quickly rescued the birds that had crashed into the nets. In the morning and afternoon, volunteers also patrol the vast net 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. "Once you make a tour, it takes about an hour." After the "evening peak" period when the birds hit the net, the sky was dark again, and the volunteers were able to finish the day's circumference work and return to the city with a tired body.
Huan Zhi is also a technical job that can be skilled. Fu Jianping still remembers the feeling of holding the bird in the palm of his hand for the first time, "grasping it for fear of being injured, and if it is loosened, it may slip away from the finger slit, especially the willow warbler, a small bird with a length of only 10 centimeters." ”
Over the years, the volunteer partners who persevered with her became the backbone of the bird ring. After this Swift Ring and research, they dedicated a mature experience.
Swifts are accustomed to breeding in crevices and caves, and their claws are very sharp because they climb on rock walls. During the ring process, if the operation is not done properly, the finger may be scratched. But the volunteers are skillful and appropriate. "There aren't so many 'confrontations' between us, they can relax."
Carry a "small school bag" for swifts and depict the laws of migration
Wear a logo ring for the Beijing Swift, weigh it, measure the length of the beak, the length of the tarsal foot, the length of the body, the length of the wings, the length of the tail, and the release... At the Summer Palace, such Beijing Swift Ring Activities lasted for many years (stopped during the epidemic). From this, people continue to refresh their understanding of swifts.
The Summer Palace's pavilion attracts a large number of swifts to nest and breed here every year. Since 1997, Gao Wu, a teacher at Capital Normal University, has led students to conduct an internship in Beijing Swift Huanzhi in Kuruting, but after 2002, Huanzhi activities were suspended. Since 2007, the China Bird Watching Association has once again launched the Beijing Swift Ring in Khoruting.
"After five years, in the same place, what we most expect is to recapture and recycle." Fu Jianping said a total of 40 Beijing swifts were captured this year, one of which was a swift that Huan Zhi had seen in 1998. The recycling information indicates that the Beijing Swift can live for at least 10 years.
Over the next 5 years, Huanzhi work improved netting strategies and techniques, and Swift recovery rates continued to rise. By 2012, the recovery rate was as high as 53%. "The high recovery rate tells us that the Beijing Swift is highly loyal to the original breeding grounds. One of the 2,000-year-old rings was recovered, indicating that the swift was at least 13 years old. This is the result of our continued environmental commitment. ”
In 2014, the international cooperation of Beijing Swift Ring Tracking Research was launched, and researchers wore photosensitive locators for Beijing Swift to study the law of its migration. Fu Jianping said that the swift's four toes are facing forward, can not be grasped, and can not be pedaled to take off after landing, so most of its life is flying, even mating, predation are carried out in the air, so when it is not in the breeding ground, it cannot be captured and record migration information through the ring. The locator can relatively accurately depict the migration path of the Beijing Swift.
Volunteer Liang Xuan and foreign experts worked together to wear positioners for Swift. Photo by Wang Yuansheng
While wearing the locator, volunteer Liang Xuan gently and forcefully held the Beijing Swift and helped foreign experts carry this "small school bag" for them. When experts put the noose on the bird's wing roots, Liang Xuan will carefully loosen one side of the swift's wing. To verify that the tightness is appropriate, the two will use a pencil to pass through the rope noose under the swift's back, which means that it is just right, so that the locator and the back of the swift leave a gap, and the rope noose will not be particularly tight, thus affecting the bird's flight. The bird's feathers 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 have won the admiration of experts.
Before 2015, the migration route of the Beijing Swift was unknown. Some speculate that after leaving Beijing, they will fly over the Himalayas to the Indian subcontinent, while others believe they flew along China's eastern coast to Southeast Asia. When Beijing Swift flew back to the Summer Palace that year, the researchers recovered the first batch of equipment. Everyone was surprised to find that the Beijing Swifts underwent an epic flight, flying to southwest Africa.
"The moment the data was read, huanzhi volunteers were particularly excited, and everyone felt that they had done something particularly meaningful." Recalling the scene 7 years ago, Fu Jianping's tone is still difficult to hide his pride.
Liang Xuan's job is to teach and research, she admits that when she first started doing bird rings, she thought it was fun and interesting, but if she persisted, she would find that it was hard and boring. Unlike bird watching, which can go to different places and see various interesting behaviors of birds, Huanzhi needs to repeat the same work in fixed places, catching birds, going to the ring, measuring, releasing... However, the study of bird migration patterns requires a lot of data accumulation, and the probability of researchers and volunteers recapturing the Beijing Swift that has been circumscribed is not high. This also means that more Beijing swifts need to be surrounded by the ring, and more people need to participate in the work of the bird ring.
"Understanding the migration of Beijing Swift is the premise of protecting them, and more people are welcome to join us in guarding the Beijing Swift." Liang Xuan said.
Beijing News reporter Zhang Lu
Edited by Bai Shuang Proofreader Wu Xingfa