The protagonist of the "Otter Fish" that disappeared for many years was found again in Zhoushan, Zhejiang? !

"There are tigers in the mountains and otters in the water." As a key species in river ecosystems, otters have a direct impact on aquatic biodiversity and are the guardians of ecosystem balance. Otters have extremely high requirements for the water quality of their habitats, and their presence often indicates that the water is clean. Therefore, otters can be regarded as water quality monitors in nature, and their population status indirectly reflects the health of the environment.

△Rescued otters

In my country, otters are listed as Class II protected animals and are facing a serious survival crisis. Take Zhejiang Province as an example. The otters that were once found throughout the province’s inland waters are no longer as common. Since the beginning of the 21st century, especially since 2000, they have almost disappeared in Zhejiang. In the past three decades, there have been only a few sightings of otters.

What species are otters? Why are they disappearing? And how can we protect them? Let's embark on a journey to find otters.

0 1Otter ? Water ghost?

In Zhejiang, otters are known as "water ghosts" because they hide during the day and come out at night, are cautious, and move in a treacherous and secretive manner, making it difficult for people to see them clearly. In fact, they do not harm humans, but are very timid and sensitive.

△Otter footprints

The otter is an amphibious mammal, a top predator and flagship species in freshwater ecosystems, and a national second-class protected animal. There are 13 species of otters in the world, and China once had 3 species. The Eurasian otter is currently the most abundant species in China.

△ Eurasian otter

The Eurasian otter is sized like a puppy, weighing about 10 kilograms when fully grown, and about a meter long, including the tail, showing the slender characteristics of mustelids. They have unique skills adapted to underwater life, thanks to a special equipment - unusually thick fur and a smooth body shape.

△Rescued otters

Studies have shown that there are tens of thousands of hairs on every square centimeter of otter skin, which is not only of high quality, but also threatened by hunting because of this luxurious covering. This dense fur has excellent waterproof performance when working underwater, and can retain air layers between the fur, effectively preventing water from penetrating quickly and maintaining body temperature, ensuring that otters can move freely and keep warm efficiently in cold waters.

Because otters have webbed paws, a flat head, and an overall streamlined shape, they move smoothly and freely when they swim in the water.

In the traditional 24 solar terms, the three phenological signs of "Rain Water" are: the otter offering sacrifice to fish, the arrival of wild geese, and the budding of grass and trees. Among them, the ancient saying of "otter offering sacrifice to fish" comes from the ancients' meticulous observation of nature. This is not a common phenomenon in modern times, so it is little known.

The significance of this is that when spring arrives, as the river water warms up and fish resources become increasingly abundant, otters display a unique behavior: they arrange the extra fish they have caught on the river bank, as if performing some kind of ritual, forming rows of fish "sacrifices."

△Jintang's "Otter Fish Festival"

The imagination of the ancients endowed this behavior with a mysterious color, and regarded it as a symbol of the otter praying for timely wind and rain and a good harvest. Once such a scene is found, it indicates that there are enough fish in the river and it is time for fishermen to carry out large-scale fishing.

In the past, otters were once domesticated by humans as working fishermen, just like cormorants, but the technique may have been lost for many years.

0 2Disappearing otters?

In the past of Zhejiang Province, otters were frequent visitors to inland water systems, widely distributed and closely connected with people's lives, leaving behind many memories and legends passed down by the older generation.

However, they have quietly faded from public view, and the reasons behind this are a mystery - is it environmental pollution that has led to deteriorating water quality? Or is it human activities such as increased hunting? Or is it the result of changes in the food chain and the spread of diseases? These questions remain unanswered, and the otter population seems to have "collectively evaporated" at a time when humans were not deeply alert, and it is difficult to find their traces.

△The river where Jintang otters live. In Zhejiang, such rivers can be seen everywhere.

Fortunately, scientific and technological progress and efforts in nature conservation have brought about a turnaround. With the help of advanced technology such as infrared cameras and targeted wildlife surveys, the research team made a breakthrough discovery on Jintang Island: more than 120 traces of otter feces and more than 800 precious images of otter activities, revealing that the island is not only the largest existing otter population in Zhejiang Province, but also the only one that can be continuously observed.

This unique and stable habitat is extremely scarce and valuable across the country and even in a wider geographical area.

Currently, the otters on the island still face many threats: the more frequent phenomenon of electric fishing has seriously disturbed the otters' natural living environment, affecting their food chain and predation behavior; oil in the river and discarded packaging of pesticides and fertilizers cause chemical pollution, affecting the health of otters and even causing disease and death; unreasonable river-blocking nets and high river banks reduce the connectivity of the otter habitat, affecting their migration and reproduction; and there may be unclear management rights in the otter living area, which may delay or hinder the implementation of effective protection measures.

△Jintang Wetland where otters appear

Together, these threats pose a serious challenge to the survival of otters and require a comprehensive conservation strategy.

0 3How can we protect otters?

The strategy for protecting otters revolves around in-depth scientific research, direct conservation intervention, and the construction of sustainable protection mechanisms, aiming to create a safer and more stable future for otters and their ecological environment.

Background survey

First of all, a comprehensive background survey is the basis, which means to have a detailed understanding and record of the otter's habitat environment, population distribution, number and ecological habits. This step will help us understand the true status of otter survival, identify threatening factors, and provide a scientific basis for subsequent protection work.

△Install infrared triggered camera to photograph otters

Scientific research

Strengthening scientific research is the key to improving conservation effectiveness. This includes but is not limited to research on the biological characteristics of otters, analysis of genetic diversity, and research on the role of otters in the ecosystem. Through scientific means, we can more accurately evaluate the effectiveness of conservation measures and explore new technologies and methods for otter conservation.

△Two otters appeared at the same time. Are they a couple or a child?

Conservation Action

Direct conservation actions are crucial, including the establishment of protected areas, the implementation of breeding programs, the rescue of injured or endangered otters, and public education and awareness raising. Efforts are made to improve local rescue capabilities by seeking administrative and financial support from local governments, establishing rescue centers/science museums, training local otter monitors, and strengthening otter protection and rescue science popularization.

△Remains of abandoned fishing gear in otter feces

Sustainable Operations

To ensure the long-term effectiveness of conservation efforts, sustainable operational management measures are needed. This involves promoting community participation and balancing nature conservation with the economic development needs of local communities, such as the Zhejiang Coastal Endangered Species Otter Community Conservation (OECM) pilot project. Through cooperation and participation, a model is established that can both protect biodiversity and meet community development needs.

△ Local otter monitor training activities