On the meadows of Coco Siri lived a small animal that resembled a rat but had no tail, a petite and strong body, furry all over, and a pair of large round ears. From time to time, they will also stick out their small heads from the mouth of the cave, and observe you with curious eyes, absolutely cute and full of points, it is what people often call the little elf - Tibetan pika.
In the early morning of summer, the Tibetan pika hurried out of the hole, straightened up, raised its small head, and bathed in the morning light. The dew hanging from the tip of the grass reflects the contented look of the Tibetan pika and the shadow of the snow sparrow bouncing on the grass. Perhaps at noon in the winter, the pikas are out of the cave, and the scene is very chaotic and disorderly. Some nibbled on the grass, some went in and out of the cave entrance, and some nestled in the sun on the ground.
Every year from April to June is the breeding season for tibetan pikas, when you will see the head of the family standing domineeringly at the mouth of the cave, making a long, sharp sound, which is declaring its position in the field. However, once the head dies, the other males will quickly occupy the family and throw all the old hay bedding from the cave outside the cave.
The Tibetan pika is a small non-hibernating plant-eating mammal called the "prairie spirit", this guy has a rounded figure and a soft fur; a rabbit-like mouth and nose, the upper lip has a distinct vertical split line, and the entire mouth is divided into three petals; and there are short round ears like rats, the ass is bare, and the tail is not extended outwards, which is cute at first glance.
The strange appearance of the Tibetan pika is often mistaken for a kind of mouse, in fact, although people are called rodents, but belong to the rabbit order, rabbits are their close relatives, the Tibetan pika's signature front teeth, but also next to a pair of shorter hind front teeth.
Even the taxonomists who first discovered them were so troubled that they could not define the subjects they belonged to or to name them. At the moment of confusion, biologists thought: like a rat is not a mouse, it is a rabbit and not like a rabbit, simply direct mouse + rabbit, just call it a pika.
The family Pika was eventually assigned to the order Rabbit, which has two genera, namely the Italian Pika and the Pika, and to this day, the Italian Pika is extinct, and there are more than 30 species of creatures in the Pika genus. Except for two species that live in North America, the remaining 28 species live in Eurasia.
Half of the 24 species of pikas living in China are endemic to China, and their habitats are mainly from the central and western parts of China to the Himalayas. The Spot-necked Pika and the North American Pika in North America have a relatively moist life, while the 28 species of pikas in Eurasia have a different fate, and the Tibetan pika and the Ili pika are the two most well-known.
Tibetan pikas are known by Tibetans as stone rabbits and singing rats, the name of the stone rabbit, derived from its living environment, most of them live in rocky grasslands at higher altitudes, living in their own dug caves. As for the song rats, it is because their calls are high-pitched and loud, similar to crisp bird songs, which are unforgettable.
Tibetan pika is a unique species of the Qinghai-Tibet Plateau, the ecological environment of the Qinghai-Tibet Plateau is very harsh, cold and low oxygen, but this small mammal has evolved and adapted very successfully, from 3200 meters to more than 5000 meters above sea level in the meadow no man's land, you can see their figure.
Tibetan pika is naturally active, the speed of digging soil is amazing, and the forelimb claws with five fingers are thinly curved, which can finely restore the blueprint of the cave structure in the brain, so that the cave designed by the Tibetan pika is very exquisite.
They also build storage rooms to store some hay as bedding for the house; they also leave small grooves along the passage to keep the room clean and tidy; they even create special nursery rooms for the cubs to live.
The caves built by the Tibetan pika can be roughly divided into three categories:
The first category is the residential cave. It is used for long-term residence, and comes with six or seven escape exits. Escape exits are dotted around the hillside bushes, and if they encounter predators such as foxes, wolves, and eagles, the Tibetan pika can quickly run into the cave and escape from other exits.
The second category is the express hotel-style cave. This type of cave has only 2-3 escape exits, and each escape exit has few branch forks.
The third type of cave is the outpost cave. The structure of this type of cave is simple, often with only one exit, the other side is sealed by mud, and the inside of the cave is short and narrow. The outpost cave is far away from the home cave and is widely scattered in all directions.
If the predator is small and burrows, then the well-intentioned ultra-thin ceiling of the Tibetan pika can play a role, they will use their thin claws to destroy the upper earth wall only 1-2 cm thick from the ground, and then jump hard to escape from the ground.
When the cold winter comes, most creatures use hibernation to survive the long and harsh winter; the Tibetan pika does not hibernate, and for them, winter is the season for them to pick food.
As a typical herbivore, the food of the Tibetan pika is nothing more than tender pasture, sedge, artemisia grass and lichen covering the surface.
When tibetan pikas go out in search of food, they will use their long front teeth to bite off the roots of plants, hold bundles of plants in their mouths horizontally, and even run and jump to transport food back to the hole; the food just picked is rich in water, so it needs to be placed in front of the house to bask in the sun, and then move back to the hole to put it away after the food dries up.
Tibetan pikas are agile by nature, often just put down a bunch of plants, they immediately can't wait, jump and jump to pick again.
These hays can be used as beds for them to sleep, and the roots, stems, leaves, seeds, etc. of some plants are transported and stored deep in the cave as food for them to survive the winter.
In the meadows of Coco Siri, common birds such as snow finches and brown-backed ground crows are very intelligent, using the caves of tibetan pikas to escape the hot sun, storms and hail during the day, while pikas use the calls of birds to spy on predators.
Some biologists say that the Tibetan pika and snow finches here reciprocally coexist in a unique way, forming a "cross-species emotion". The Tibetan pika can use the singing of snow sparrows to alarm them, and the snow finches can use their burrows to avoid the sun's strong radiation or storms and hail.
Some biologists believe that birds and mice are in the same cave, snow finches are the biggest beneficiaries, in the open environment of the plateau, there are few hidden objects, it is because of the protection of the rat nest, snow finches can survive and reproduce.
Other biologists believe that birds and mice are the beneficiaries of the same cave Tibetan pika, because there are very few parasites on the Tibetan pika, and they believe that the snow sparrow acts as the family doctor of the pika and eliminates the parasite for it.
The pika and the snowfinches thus formed a cross-racial mutual aid relationship. This phenomenon is also recorded in the Classic of Mountains and Seas in china's ancient classics, and is called "birds and mice in the same cave". In any case, this seemingly aberrant but harmonious combination is indeed a miracle created by the extraordinary imagination of nature.
As for whether some birds and finches really live in the same room and peaceful coexistence with pikas, there is no conclusive evidence to prove it.
Today, nearly 90% of China's alpine meadows have been degraded to varying degrees, and pikas have long been classified as the culprits of the degradation of plateau grasslands, and they have been systematically culled for 60 years, and once wanted to kill them all. You must know that if the grassland is seriously degraded, it will not only destroy the grassland ecosystem, but also affect the production and life of the pastoral area.
In recent years, many universities and scientific research units at home and abroad, including the Chinese Academy of Sciences, have conducted a lot of research on the pika, and finally reached a unanimous conclusion: the pika has been wronged! The first to defend the plateau pika were scientists at the College of Life Sciences at Arizona State University, who believed that the pika was not only harmless, but also a "key species" in the alpine meadow area.
Experts explain that pikas feed a large group of high-level food chains. In such a special environment as the Qinghai-Tibet Plateau, the presence of pikas has become the prey of almost all predators on the plateau, and animals such as wolves, foxes, bears, falcons, and eagles rely on pikas for survival. And, due to the lack of trees in the highland environment, the burrows dug by pikas provide important habitats and breeding grounds for many birds, as well as amphibians.
More importantly, due to the compensatory effect, the pika nibbling on grass leaves will stimulate plant growth. Drilling holes can help renovate the soil, speed up the material circulation of the soil, facilitate vegetation restoration, and improve the diversity of the surrounding plant communities. While increasing soil permeability, the cave will also accelerate the infiltration of water, thereby improving the water solidity capacity and water content of the soil, which in turn slows down soil erosion.
Surveys have shown that the area where pikas are poisoned not only has the birds of prey basically disappeared, but even the number of geotopic birds that rely on pika burrows has also decreased significantly. In fact, pikas are the result of the degradation of plateau meadows, not the cause, and they are indispensable to maintaining the integrity of plateau ecosystems and are a key species among them.
Experts believe that the pika is not the cause of grassland degradation, but the result of grassland degradation, and overgrazing is the most important cause of grassland degradation. Xuelinggu believes that whether it is grazing or pika activity, when they are in the optimal number range, they will not have a negative effect on grasslands and ecosystems, which requires appropriate control and management. Do you think the degradation of the grass is caused by the pika?
Xuelinggu Nature Lab/Production
References: Northwest Institute of Plateau Biology, Chinese Academy of Sciences, China Science Daily, China Animal Digital Museum