Ex situ conservation protects our elk from getting lost

Produced by: Science Popularization China

Produced by: Bai Jiade, Zhang Shumiao, Li Yiping, Chen Qi (Beijing Elk Ecological Experimental Center)

Producer: Computer Network Information Center, Chinese Academy of Sciences

Around 1900, the endemic species, the Elaphus deer, which was once widely distributed in my country, became extinct in its native China.

In order to restore this precious species, China reintroduced 77 elk from the UK from 1985 to 1987. The population has now expanded to more than 10,000, and the distribution area has also expanded from the initial 2 reintroductions to 83. The restoration of the elk population has become a successful example of ex situ conservation of wild animals in my country.

Elk (Photo source: Elk Park album)

The so-called "ex situ conservation", as the name suggests, is a way of conservation to effectively protect a species by moving it from one place to another suitable place for it to live and reproduce. In the actual work process, ex situ conservation faces many difficulties and problems.

Why is ex situ conservation necessary?

It needs to be emphasized that the best strategy for biodiversity conservation is to protect species populations and their ecosystems in their original habitats, that is, in situ conservation or in situ protection.

However, in situ conservation is unlikely to be effective when the last remaining populations of a rare species are too small to sustain, when conservation measures have failed to prevent its decline in the wild, or when the last remaining individuals are already outside protected areas.

In this case, the best way to prevent its extinction is to place the individuals in an environment suitable for their habitat and protect them. This conservation strategy is called ex situ conservation.

Elk herd photo source: Elk Park album

Ex situ conservation is a complementary form of conservation to in situ conservation, which enables long-term preservation, analysis, testing, and reproduction of threatened or rare animal species.

The principle of implementing ex situ conservation given by the World Conservation Union is that when the wild population of an endangered species (especially higher and large species) is less than 1,000, a self-sustaining population should be established under artificial breeding conditions.

Elks eating (Photo source: Xinhuanet)

Therefore, ex situ conservation is often a very important and necessary conservation measure for species whose populations are declining sharply. For species that are not yet seriously threatened, establishing ex situ conservation populations is also conducive to scientists quickly obtaining scientific research materials, reducing the acquisition of wild resources, and promoting sustainable resource utilization.

On the one hand, ex situ conservation provides species that have difficulty surviving in the wild with a last chance of survival, protecting populations of rare and endangered species.

On the other hand, it also preserves a reserve gene pool for rare and endangered species, provides a seed source for creating new populations, and provides conditions for scientists to carry out various scientific experiments and research;

Not only that, ex situ conservation sites often also provide displays and experiences to the public, and have the functions of natural display, scientific education and ecological experience.

So, how is ex situ conservation carried out? Let’s first look at the case of elk population recovery.

Elk (Photo source: www.biolib.cz)

The process of ex situ conservation of elk in my country

The Elaphe deer in China has gone through a legendary journey of flourishing populations, local extinction, wandering overseas, reintroduction, population rejuvenation, relocation and establishment, release into the wild, and formation of natural populations.

my country's ex situ conservation process for elk has been recognized worldwide and is known as the "Chinese model for world wildlife conservation". It is a model for ex situ conservation and return of biological species to nature in the world, and has contributed Chinese wisdom to the protection of endangered wildlife around the world.

Elk herd (Photo source: Elk Park album)

The elk began to develop in the Pleistocene and reached its heyday in the mid-Holocene. After the Shang and Zhou dynasties, the elk population gradually declined and became extinct in its native China around 1900.

The return of elk to China began in 1965. In 1965 and 1973, the Zoological Society of London donated four pairs of elk to China and kept them in the Beijing Zoo. In 1980, Harbin Zoo obtained a pair of elk from Canada through animal exchange.

However, the elk did not reproduce successfully in these two zoos. Therefore, Chinese and foreign scientists proposed to return the elk to its native habitat and restore its wild population, which received positive responses and support from the Chinese and British governments.

In 1985, the Chinese government launched a project to reintroduce elk. In 1985 and 1987, 38 elk (5 males and 33 females) were brought back from Woburn Abbey in the UK and kept in a semi-natural environment in Beijing Nanhaizi Elk Park; in 1986, Jiangsu Dafeng Elk Reserve brought back 39 elk (13 males and 26 females) from 9 zoos in the UK.

A herd of elks (Photo source: Beijing Elk Ecological Experiment Center Science Education Base)

There are two goals for the reintroduction of elk: one is to restore the population by bringing back elk from abroad; the other is to release the rejuvenated elk in captivity into the suitable wild environment of its historical distribution area to restore the wild population.

To this end, elk conservation workers have developed a "three-step" strategy:

The first step is to restore the elk population to have a sufficient basic population;

The second step is to carry out ex situ population construction, and systematically disperse the elk to places across the country suitable for elk to continue to expand the population, increase the distribution area, and improve the genetic diversity of elk;

The third step is to restore a self-sustaining wild population by releasing elk into the wild through rewilding training, allowing them to fully adapt to the wild environment and achieve self-reproduction of the wild population.

1. Population rejuvenation stage

Beijing Nanhaizi Elk Park and Jiangsu Dafeng Elk National Nature Reserve have undertaken the task of rejuvenating the initially introduced elk populations.

Beijing Nanhaizi Elk Park is the origin of the model specimen and the last place of extinction of the elk. It pioneered the breeding work after the reintroduction of the elk, and achieved the first phase goal of the reintroduction of the elk in 1991 - to have a basic population of 60-80 elks in China.

By 1996, the number of elk in Beijing Elk Park reached 250. In order to continue to expand the population and maintain a balanced relationship between the elk population and the environmental carrying capacity, Beijing Elk Park has continuously exported elk to other suitable habitats, keeping the number of elk in the park at around 150. In September 2021, the number of elk in Beijing Nanhaizi Elk Park was 183.

After the introduction of elk into Jiangsu Dafeng Elk National Nature Reserve, the elk population has expanded year by year, reaching twice the initial population in 1990 and 388 in 1996. In September 2021, the number of elk in Dafeng, Jiangsu has exceeded 6,000.

2. Relocation and colonization stage

Beijing Nanhaizi Elk Park and Jiangsu Dafeng Elk National Nature Reserve have both formulated elk ex situ protection plans, and will transport elk to other historical distribution areas from time to time.

Beijing Elk Park began exporting elk in 1988, and as of the end of 2020, a total of 546 elk had been exported; Jiangsu Dafeng Elk National Nature Reserve began exporting elk in 1995, and as of the end of 2020, a total of 164 elk had been exported.

Hubei Shishou Nature Reserve and other ex situ conservation sites for elk have also gradually exported elk after the local population was rebuilt. By 2021, 83 ex situ conservation populations of elk had been established across the country.

3. Reintroduction

In 1993, the elks exported by Beijing Elk Park first received wild reintroduction adaptation training in Hubei Shishou Elk National Nature Reserve. In 1994 and 2002, Beijing Elk Park sent 34 and 30 elks to Hubei Shishou Elk National Nature Reserve respectively to carry out the wild reintroduction experiment of elks.

In 1998, the Yangtze River flooded, and 34 elks that were undergoing wild training in the core area of ​​Hubei Shishou Nature Reserve took advantage of the flood to escape to the three neighboring areas of Dongting Lake, Yangpotan and Sanheyuan in Hunan Province. By the end of 2020, the natural populations formed by the escaped groups in the three areas exceeded 200.

In 1998, the Dafeng Elk Reserve selected eight elks for the first wild release experiment. Since then, the Dafeng Reserve has continued to carry out wild release, and by 2020, a wild population of 1,820 elks had been formed, basically achieving the goal of restoring the wild population.

In 2018, 47 elks were released into the Poyang Lake wetland area in Jiangxi Province. They have now been able to reproduce freely in the wild and are showing a trend of spreading outward. The successful reproduction of elks in the Poyang Lake area marks the success of rebuilding the wild population of elks in the original distribution area of ​​China's largest freshwater lake.

Elk began to gather in large groups on the grasslands of Poyang Lake (Photo source: Jiangxi Daily)

The “Three-step” strategy: China’s plan to build a global community of life

The reintroduction of elk into conservation efforts will bring a species that was once extinct for nearly a hundred years back to its native habitat. It is a long and complex project full of uncertainties, and there are no successful cases to learn from internationally.

Generations of elk protection researchers in my country have not been afraid of difficulties and have worked hard one after another. Based on a careful analysis of the reasons why the elk population could not be successfully restored after the reintroduction in the Beijing Zoo and Harbin Zoo from 1965 to 1980, they have been brave in exploration and continuous summary, overcoming numerous difficulties and solving problems such as high mortality rate in small populations, low survival rate and reproductive capacity, difficulty in identifying natural enemies, and many invisible diseases.

Not only did it summarize the scientific management experience based on the laws of genetics and population biology, it also overcame the three major technical difficulties of breeding and seed conservation, feeding management and disease prevention and control, and explored a set of appropriate methods for the reconstruction of the elk population.

The successful protection of the elk species is a powerful testimony to the fact that “the prosperity of the country leads to the prosperity of the elk.” Population restoration, relocation and reintroduction are all part of China’s “three-step” strategy for protecting elk.

Under the guidance of the "Three-Step" strategy and nearly 40 years of persistent efforts by Beijing Elk Park, Jiangsu Dafeng Elk National Nature Reserve and other units, the elk, a world endangered species that had been extinct in the wild in my country for more than 100 years, has grown from the original 77 to over 10,000 today.

After breaking through the genetic bottleneck of a small founding population and high inbreeding, the elk has spread across the country, basically covering the original distribution range of the elk, close to the historical distribution area, and completely getting rid of the risk of extinction. This also confirms that the "three-step" strategy for the reconstruction of the wild population of elk is an effective model for ex situ protection of endangered wild animals in the world.

The ex situ conservation of elk is a monument in the history of wildlife conservation in my country. It has contributed to the construction of ecological civilization and a beautiful China, and also contributed the Chinese solution to building a community of life on Earth.