Crocodile: The misunderstood “game”

Some people think that crocodiles are just ugly "monsters", but in fact, the whole body of the crocodile is a treasure. Artificial breeding of crocodiles is of great significance in studying biological evolution and increasing population size, and should be taken seriously.

Written by reporter Zhao Tianyu Photo and text editor: Ding Lin Zhao Tianyu

New Media Editor/Li Yunfeng

Interview experts

Wu Xiaobing (Professor and doctoral supervisor at the School of Life Sciences, Anhui Normal University)

Xu Jinwang (General Manager of Hainan Xieyuan Agricultural Development Co., Ltd.)

Not long ago, a video of "a frozen crocodile bought online and revived" went viral online. The video showed that when someone chopped the crocodile's head with a kitchen knife, the crocodile was still jumping on the floor. The relevant e-commerce platform stated that the crocodiles sold on the platform were Siamese crocodiles that were formally farmed in Inner Mongolia, and that they were all eviscerated before delivery, so there was no possibility of hibernation or resurrection.

Some people think that crocodiles are just ugly "monsters", while others think that crocodile meat is "game" and cannot be eaten. In fact, the domestic crocodile farming industry has embarked on the road of formalization and scale operation. However, compared with traditional aquaculture products such as soft-shelled turtles, bullfrogs, and crayfish, the standardization of crocodile farming and social recognition need to be improved.

▲Crocodiles raised at the Dakida Crocodile Farm in Yangon, Myanmar (Source: Xinhuanet)

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Crocodiles are not fish, but they are full of treasures

Crocodilians are commonly known as crocodiles, but they are not "fish" but the oldest type of reptiles in the world. Crocodiles are veritable "living fossils" and have lived on Earth 200 million years ago.

There are 3 families, 8 genera and 23 species of crocodilians in the world, most of which are distributed in tropical and subtropical areas such as Africa, Central America and southern Asia. The most suitable living environment for them is generally above 30 degrees Celsius. Only the Yangtze alligator in my country and the Mississippi alligator in North America are distributed in temperate zones.

In the eyes of many people, crocodiles are ugly, ferocious "monsters" that only eat people, but no one eats them. However, in some areas in southern my country, especially in Guangdong, Guangxi and Hainan, crocodiles have been a delicacy since ancient times and have high nutritional value.

As early as in the Ming Dynasty, medical scientist Li Shizhen once recorded in Compendium of Materia Medica: "People in the south treasure the meat and regard it as a sign of respect at weddings." This means that people in the south admire crocodile meat and regard it as a delicacy at wedding banquets.

Hundreds of years later, according to media reports, Guangdong has become the main area of ​​crocodile consumption in the country. It is conservatively estimated that at least 100,000 crocodiles are eaten by Guangdong people every year.

▲Crocodile meat sold at the night market (Source: Strait City Network)

Modern medicine has proven that crocodile meat, bones, shells and internal organs contain not only high-quality protein and essential amino acids for the human body, but also a variety of unsaturated fatty acids, vitamins and trace mineral elements. In addition to its meat value, the crocodile's back leather is strong and can be used to make high-quality leather shoes and belts; its belly leather is flat and soft, which can be called the "gold" among leather goods, and is sought after by the fashion industry and has excellent commercial value.

In the past, due to hunting and habitat loss, the number of wild crocodiles has dropped sharply, and some crocodiles have become endangered species. In 1973, the International Wildlife Protection Conference listed wild crocodiles as endangered species and banned species. All wild reptiles and crocodilians are listed in Appendix I and Appendix II of the Washington Convention (CITES) (Convention on International Trade in Endangered Species of Wild Fauna and Flora), prohibiting or controlling their international trade.

Although hunting wild crocodiles is prohibited, crocodiles' high ecological value, scientific value and economic value make them popular in the artificial breeding industry.

Professor Wu Xiaobing, a doctoral supervisor at the School of Life Sciences of Anhui Normal University and a long-time crocodile researcher, told reporters that the world's first crocodile farm was built in 1893, but its main purpose was to provide viewing for people. Modern commercial crocodile farming began in the 1970s and has since developed rapidly. According to estimates by the World Crocodile Specialist Group (CSG), there are currently about 4,000 to 5,000 crocodile farms around the world, breeding more than 20 species, and the annual economic benefits have reached tens of billions of dollars.

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Common crocodile species farmed in China

Compared with Australia and Southeast Asia, the scale of crocodile breeding in China is still small. Currently, the crocodiles domestically bred are mainly Siamese crocodiles, Nile crocodiles, saltwater crocodiles and Chinese alligators, as well as a small number of American alligators and caimans.

Among these farmed crocodiles, the country currently allows only three types of crocodiles to be commercially utilized (commercial trading is allowed): the Siamese crocodile, the saltwater crocodile and the Nile crocodile.

"Affected by factors such as climate and market, my country's crocodile farms are mainly concentrated in the southern region, and the main breeds are Siamese crocodiles and Nile crocodiles. In recent years, with the maturity of greenhouse technology, many cities in the north have also had the conditions for raising crocodiles, but at present, crocodile farming generally maintains a situation of more in the south and less in the north." Wu Xiaobing said.

▲ Saltwater crocodile (Source: Changsha Evening News)

The saltwater crocodile is not only the largest of the farmed crocodiles, but also the largest reptile in existence. Visually, it looks "fat and long". When it grows up, it can reach a size of about 3-5 meters and weigh more than 1.6 tons. It is the only species in the crocodile family without a neck shield. The saltwater crocodile has a light color and its back is mostly spotted. Because of its large size and beautiful patterns, the saltwater crocodile leather has the best commercial value among farmed crocodile leathers.

Wild saltwater crocodiles live at the junction of salt and fresh water. Due to excessive hunting by humans, they were once on the verge of extinction, with a population of less than 5,000. Later, under the protection of various countries, the number of saltwater crocodiles began to grow rapidly, especially in Australia, where the population has exceeded 200,000.

▲Nile crocodile (Source: Xinhuanet)

The Nile crocodile is native to Africa. It is slightly smaller than the saltwater crocodile, but can reach about 4 meters in length, making it the second largest reptile after the saltwater crocodile. The Nile crocodile is dark in color, mostly yellow-green and gray-green, and has 6 shields distributed on its neck, 4 in front and 2 in the back.

Nile crocodiles are ferocious and are the "super overlords" of African rivers. They often prey on larger animals such as antelopes and zebras. my country introduced the first batch of artificially bred Nile crocodiles from South Africa in 1995. Due to the lack of breeding experience, there have been cases of crocodiles killing each other.

▲Siamese crocodile (Source: Dandong News Network)

The Siamese crocodile, also known as the Thai crocodile or the Vietnamese crocodile, is the cheapest and smallest of the artificially bred crocodiles, with an adult length of only 1.5-2.8 meters. The Siamese crocodile is docile in nature, not only will it not actively attack people, but it is even a little "timid" and likes to hide in the water.

The Siamese crocodile is one of the most artificially raised crocodiles in my country. It has the advantages of strong reproductive capacity, fast growth, and strong disease resistance. Its leather products are very cost-effective and are welcomed and recognized by the market. The Siamese crocodile can also hybridize with other crocodiles. The crocodile in the "crocodile video" incident may be a "fake Siamese crocodile" hybridized in this way.

▲ Yangtze alligator (Source: cgtn)

The Yangtze alligator is a species of alligator unique to my country. It is mainly distributed in the lower tributaries of the Yangtze River in five cities and counties in southern Anhui Province. It was once on the verge of extinction. Since the 1970s, my country has saved the Yangtze alligator from the danger of complete extinction by establishing nature reserves, improving the habitat of wild alligators, carrying out artificial breeding of alligators, and actively implementing the wild release project.

Wu Xiaobing said that although the number of wild alligators has increased and the artificial population has exceeded 20,000, they have not yet been removed from the list of endangered species, and overall there is still a big gap between them and the Siamese crocodile and the Nile crocodile. At this stage, the breeding of alligators is not commercially viable except for tourism.

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The market potential is still huge, and standards and norms need to be put in place first

The development of the crocodile breeding industry in China has been full of twists and turns. It has experienced gaps in policies and regulations, changes in competent authorities, etc., and has only recently stabilized.

my country introduced crocodile breeding technology from the international market as early as 1993, but in the 1990s, when industry standards were not standardized and the market did not pay enough attention, artificially bred crocodiles were still regarded as a kind of "game" and were in a "gray" state. It was not until 2005 that the Siamese crocodile, saltwater crocodile and Nile crocodile were officially included in the first list of 54 terrestrial wild animals that could be commercially exploited, and the domestic breeding market began to develop rapidly.

After the outbreak of the COVID-19 pandemic, the expected ban on eating wild animals has added uncertainty to the industry. In June 2020, relevant departments issued a clear policy stating that artificially bred populations of three crocodiles, Siamese crocodiles, Nile crocodiles, and saltwater crocodiles, are not considered wild animals and can be put on the market in accordance with the law.

▲Tourists are visiting a crocodile breeding farm (Source: Yunfu News)

"The crocodile farming industry is not just a niche industry, it should be described as 'too small'," Xu Jinwang, general manager of Hainan Xi'eyuan Agricultural Development Co., Ltd., a crocodile farming company, told reporters. He believes that among freshwater farmed animals, crocodiles are actually the safest, most stable and healthiest species, with low labor input and raw material costs. However, the domestic public currently does not pay enough attention to crocodile farming, the market is not open to a high degree, and there are no large companies involved. The industry lacks unified standards, and farming experience is basically passed on by word of mouth.

Xu Jinwang suggested that relevant departments should issue industry standards for crocodile breeding as soon as possible, pay attention to the promotion of breeding technology, and cultivate excellent varieties suitable for Chinese breeding. In addition, efforts should be made to popularize relevant science and establish a positive image of artificially bred crocodiles to the public, so that people will no longer be afraid of crocodiles.

In Wu Xiaobing's opinion, my country's crocodile breeding industry has great potential, but there are still some problems that need to be solved for its future smooth development, such as the establishment of breeding standards and specifications, the popularization of breeding safety awareness, the definition of growth standards for different products, and the clarification of the crocodile seed source status.

For example, in terms of the standards for crocodile farming, in order to prevent crocodiles from escaping, current regulations require that farms build two walls, but many small and medium-sized farming companies do not comply with them, and crocodile escapes occur from time to time, sometimes even causing considerable panic among the public; artificially farmed crocodiles are managed as aquatic species, but the aquaculture industry has not yet had quarantine standards for crocodile slaughter; in addition, crocodile farming technology has always been at a low level, and the survival rate and reproduction rate are not very optimistic.

It is reported that from December 2020, under the guidance of the Fisheries Administration of the Ministry of Agriculture and Rural Affairs, the national farmed crocodile and its products identification management system began trial operation, and artificially bred Siamese crocodiles, Nile crocodiles and saltwater crocodiles and other products can be put on the market with the "National Crocodile Breeding Identification". These measures ensure the standardized development of the crocodile industry and explore a feasible path for the standardized management of aquatic wild protected animals.

Wu Xiaobing pointed out that artificially raised crocodiles play an important role and significance in studying biological evolution, protecting endangered species, and increasing populations. There are not many studies on crocodiles in China, and the degree of attention paid to artificial breeding is not high, but there is actually a lot of room for improvement. If we can conduct in-depth research and development on artificial hatching and breeding of crocodiles based on local artificial breeding experience and with the help of the latest research results at home and abroad, it will be very valuable in all aspects.

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Produced by: Beijing Science and Technology News | Beijing Science and Technology Media

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