For the first time in more than 40 years! A new species called "Beijing" appeared in Chaobai River. Who is it?

In January this year, a research team from the Institute of Zoology, Chinese Academy of Sciences, published a new fish species collected from Beijing, the Beijing loach, in the internationally renowned zoological journal Zoosystematics and Evolution. This is the first time a new fish species has been discovered in Beijing in more than 40 years since 1981.

The world's first fish species named after the new pinyin "Beijing"

Beijing loach (Cobitis beijingensis) is the world's first fish species named after the new pinyin "Beijing". The species is scattered in water bodies such as Chaobai River in Beijing, and the population is relatively rare. In recent years, the relevant team of the Institute of Zoology of the Chinese Academy of Sciences has gradually accumulated specimens during the continuous investigation in Beijing. Through many scientific methods such as morphology and molecules, it was confirmed that the species is a new species.

In appearance, the Beijing flower loach is similar to the "spotted flower loach" in Beijing. However, the spotted flower loach is commonly found in mountain streams, while the Beijing flower loach prefers the slow-flowing and still water environment near the mountainous area. It is especially easy to find the Beijing flower loach in clear water bodies with slow flow, muddy bottom and lush aquatic plants, such as the Huaisha River-Huaijiu River Conservation Area in Huairou District and the shallow water area of ​​Chaobai River in Miyun District.

Zhao Yahui, the head of the research team, said that the discovery of the Beijing flower loach is also a sign that the fish diversity in Beijing is showing a positive trend. "The flower loach was named 'Beijing' for protection purposes. We hope to link this species with the city and use it as a 'symbol' of Beijing's freshwater fish. While paying attention to this species, other indigenous fish in Beijing will also receive corresponding protection."

Ancient traces of fish in Beijing

Fish cannot live without water. Generally speaking, all rivers in Beijing belong to the Haihe River Basin, which are divided into five different water systems. In the north and northwest, it is mainly the Chaobai River system, which is where the Chaohe River and the Baihe River flow into the Miyun Reservoir. In the west, it is mainly the Yongding River system, with the Guanting Reservoir as the core, and then it enters Beijing again from Mentougou, belonging to the Yongding River system. The water bodies in Beijing's urban area belong to the Beiyun River system, which is part of the original Grand Canal. There is also a small part in the east that belongs to the Jiyun River system. In the south and southwest of Beijing, it is mainly the Daqing River system, such as the Juma River.

Some fish fossils have been discovered in Beijing. For example, in the Mesozoic era between 250 million and 65 million years ago, some cartilaginous and scaly fish fossils were discovered in Badachu, Xishan. In the Jurassic period, some primitive bony fish fossils were also discovered, such as wolf-finned fish.

▲Primitive bony fish fossils from the late Jurassic period

A large number of fish fossils were also found in Zhoukoudian. These fossils were identified as belonging to the subfamily of barbels, which are fish that prefer warm and humid climate conditions. At present, most of the species of the subfamily of barbels in our country are distributed south of the Yangtze River. Therefore, the discovery of fossils in Beijing also shows from a certain perspective that the actual climate conditions in Beijing during the Peking Man era were different from those of today, warmer, more humid, and more suitable for human activities.

From foreign scholars to local exploration

The research on living fish in Beijing can be divided into two periods. One period started from 1855 and lasted until the 1930s. A feature of this period is that the research on living fish was basically done by foreign scholars. For example, in 1855, the Russian ichthyologist Basiliuski described a fish found in Beijing. He named this fish after Beijing. This is the bream that we often see on the table. Its Latin name is Beijing bream.

▲The Beijing bream discovered by Russian ichthyologist Basiliuski in the Beijing area

After the 1930s, some important scholars in my country began to conduct detailed investigations on the distribution of fish in Beijing. After the founding of the People's Republic of China, different units and research institutions also successively conducted research on some specific species in Beijing. Among them, the most important one was the publication of "Beijing Fishes" in 1984. This was the first time that all the fish distributed in Beijing were sorted out in a relatively complete and systematic manner.

After 2000, the team of the Institute of Zoology of the Chinese Academy of Sciences conducted more investigations around Beijing. In 2013, the book "Fish in Beijing and Its Adjacent Areas" once again described the status of fish in Beijing.

In the past, there were about 85 species of fish found in natural waters in Beijing, including 7 species introduced for aquaculture. There are 78 species of wild fish naturally distributed in Beijing's waters, including 5 species of fish distributed in brackish and freshwater. If these are removed, there are only 73 species of pure freshwater fish distributed in Beijing.

What changes have Beijing’s wild fish species experienced?

The species diversity of fish in Beijing first decreased and then increased.

From the 1930s to the 1980s, about 15 species of fish disappeared. The main reason was the large-scale water conservancy construction in the 1950s and 1960s, such as the construction of sluice gates and large reservoirs, which blocked the passage of migratory fish. As a result, Japanese eels, silver carp, etc. disappeared from Beijing's waters.

From the 1980s to the 2010s, the rate of species disappearance accelerated, with about 30 fish species becoming extinct, mainly due to rapid urban expansion and population growth, which destroyed the natural water environment. Overfishing also exacerbated the crisis. There were originally 42 species of fish in the Juma River in Fangshan, but only 20 species remained when the survey was conducted; the pointed plateau loach, thin loach, Japanese eel, and phoenix anchovy were basically extinct in Beijing waters; the fine-scaled salmon, Walleye, and multi-scaled white snapper have not been seen for many years, and the distribution area of ​​the Chinese spiny fish has been greatly reduced.

After 2014, fish diversity in Beijing began to improve. Due to the key protection of Miyun Reservoir, the diversity of wild fish species in Chaobai River system remained stable. The number of species in Yongding River increased significantly after 2016, and the species diversity in Beiyunhe River system also increased significantly.

Huaisha River and Huaijiu River upstream of Huairou Reservoir are key aquatic biological protection areas, and the number of fish species increased from 21 in 2004 to 33 in 2016. The Summer Palace is an urban fish protection island, and the number of fish surveyed in 2019 increased by 71% compared with 2005-2006. The Chinese mackerel, a second-class protected animal in Beijing, used to be rare in mountain waters, but now it is easy to find in urban waters.

▲In recent years, surveys have shown that the distribution of mackerel can be easily found in urban water bodies.

The completion of the South-to-North Water Diversion Project has replenished water for urban river and lake systems and provided a more suitable living environment for wild fish. It is one of the important reasons for the increase in fish species and numbers.

Source: Beijing News, Capital Science Lecture Hall