The number of Chinese terns, one of the world’s rarest seabirds, increased by deception. Ornithologists have posted on several uninhabited Islands in the East China sea fake colony of the plastic birds and lost their voices. So they are attracted to nesting crested terns, among which are settled and far more rare Chinese. The result of these efforts and other conservation measures was the increase in the number of endangered species with 50 to 100 adults, report scientists in the journal Biological Conservation.
About one-third of seabird species are threatened with extinction due to human activities. The poor condition of their populations is due to several factors: including anxiety, spread of alien species, overexploitation of marine resources, destruction of fishing gear and climate change.
Special anxiety of the watchers is the fate of the Chinese tern (Thalasseus bernsteini), which breeds on small Islands in the East China and Yellow seas. First described in the mid-nineteenth century, it has not caught the eye of researchers since 1937 and for decades was considered extinct until in 2000 a few breeding pairs were discovered on the matsu archipelago in the Northern part of the Taiwan Strait.
Over the past 20 years, the Chinese terns nesting was confirmed at five points. However, the population of this species does not exceed 100 adults, making it one of the rarest seabirds. The international Union for conservation of nature classifies Chinese tern species on the verge of extinction (Critically Endangered, CR), and experts desperately trying to save this species.
One of the projects to rescue the Chinese tern was put into practice by a team of ornithologists led by Shuihua Chen (Shuihua Chen) from Zhejiang Museum of natural history. His goal was to bring back rare birds to the archipelago of Tsusan where they’ve nested before 2007, but disappeared due to illegal collection of eggs.
Experts have used an unusual tactic: they placed on belonging to the archipelago island Tidung Tao dummies terns and lost their shouts. It may seem strange that the sea birds lend themselves to such a gross deception, however, this technique has become well established themselves in environmental projects around the world. Interestingly, ornithologists were attracted not rare Chinese terns, and their more numerous cousins the crested terns (T. bergii). The fact that the first nest only in large colonies second. Thus, the new colony of crested terns increases the chances of Chinese nesting terns.
Work on the island began in the spring of 2013, a month before the start of the season. In total here has installed 350 dummies crested terns and 50 dummies Chinese terns and two speakers for playback of their voices. In addition to social involvement, ornithologists using the poisons destroyed the local population of potential predators — rats, Rattus losea, and also prepared the ground for nesting.
Terns of both species began to appear on Tedung Dao in 2013. By August it was noted the 3300 and 19 Chinese crested terns. At least two pairs of Chinese terns have nested and brought up one nestling. In 2014, these birds were already 43, and the number of Chicks has increased to 13. In 2015 was born 16 Chicks. 2016 issued for the colonies failed: on Tedung Tao entered keeled rat snakes (Elaphe carinata). Fortunately, they managed to catch, and in 2017 and 2018 Chinese terns again were able to bring a few Chicks.
In 2015, ornithologists have launched a similar project on the Islands of Fujisan. This is a mixed colony of terns already existed, but experts decided to expand its social involvement. As a result, the numbers of both species increased. Thus, the number of Chinese Chicks terns increased from four in 2015 to 12 in 2018.
The results confirm that social involvement is ideal to restore the population of Chinese terns. Based on this methodology, projects, along with other conservation measures have helped to increase the population of this endangered species from 50 to more than 100 individuals. It is still a very small figure, but it is encouraging that the Chinese tern manage to survive. The authors recommend to continue work on the restoration of mixed colonies of terns along the coast of the East China sea.
Another rare bird species that needs human assistance — island shrub the Jay, live on the only island of Santa Cruz off the coast of California. Now this bird, there is little danger, however, in the future on her home island can penetrate the deadly West Nile virus. To increase the chances of jays survival, the birdwatchers , offer to do them vaccinated and resettle part of the population on the neighbouring island.
Sergey Knee High