The locust swarms flew, and there was little grass left where they passed. At the moment of crisis, a large flock of birds flew from the sky, and they fell from the sky and landed on the grass to hunt for the raging locusts.
A few years ago, a locust plague broke out in northern Xinjiang, covering more than 30 million mu (201 hectares) of affected grasslands throughout Xinjiang, and locust groups gathered and migrated, leaving little pasture left where they passed. In the northern part of the Kalamaili Reserve, where more than 100 locusts per square meter are nibbling on the grasslands, the "grass-livestock-man" food chain in the desert grasslands has been destroyed, artificial locust extermination has had little effect, and the large herbivores in the reserves are already facing a "food shortage" crisis.
Just when people were helpless, one day, out of nowhere, a large group of birds slightly smaller than magpies flew down from the sky and landed on the grass to hunt for the raging locusts. In about 3 days, the density of locusts was greatly reduced, and the locust infestation was lifted. So, where is this little elf, and how can he have such divine power? It turns out that this is the grassland "locust harvester" that people often refer to - the pink starling.
Passeriformes of the genus Pink Starling, Starling family, Starling genus. Starlings are a large family with 28 genera and 114 species, with members all over the world, there are 3 genera and 18 species in China alone, some of which are quite famous, such as the savage and wrens who can speak the tao are members of their families. Pink starling is an ordinary member of the starling family, medium size, adult bird body length of 19 ~ 22 cm, weight 60 ~ 73 grams, flying feathers, tail feathers are bright black, the back, chest and two ribs are pink, so it is called pink starling. Females and males have similar coat color, but are duller. Pink starling is mainly distributed in eastern Europe to central and western Asia, and migrates to India and other warm belts of South Asia in winter, and Xinjiang in China is the main breeding ground of pink starling. Pink starlings like to live in groups, have the habit of working at sunrise and resting at sunset, and they also like to be lively, often gathering together and making noises.
Every year from May to June, pink starlings migrate to breeding grounds in flocks, first settling in low mountains where food is abundant, and then choosing nest sites in clusters to occupy stone piles, cliff crevices, etc. In order to compete for favorable terrain, fierce battles between males often occur. The upper feathers on the top of the male's head are unfurled to intimidate other males and attract females. After several days of selection, a "monogamous" family was finally formed, and they began to build nests together and prepare to breed offspring.
Pink starling breeds a generation every year, laying 3 to 8 eggs per clutch, hatching 15 days after the chicks break out of the shell, after 15 to 20 days of parent feeding before leaving the nest with their parents, after leaving the nest also need parents to feed for a period of time, and follow the parents to learn predation skills. Pink starlings eat a large amount of food, each adult bird eats 120 to 170 locusts a day, and the total weight of these locusts exceeds the weight of the birds themselves. As chicks grow up, their food intake increases dramatically, even exceeding that of adult birds. Good appetite and large food intake are one of the reasons why pink starlings have become experts in locust extermination.
Pink starlings are good at teamwork, and living in groups is their most important social behavior characteristic. Whether on a long journey or in a nesting ground for breeding offspring, they are in droves, and they have to accompany them when they go out to forage. Researchers have observed a migratory flock of pink starlings in groups of more than 10,000, which can be described as shading the sky when the birds skim across the sky. However, in most cases, the number of a migratory group is 30 to 150.
After migrating to the breeding area, pink starlings gathered in large flocks and began to nest among the rubble piles. The neighborhood is very close, with 2 to 5 bird nests per square meter, and one nest area can accommodate hundreds of "families". It seems crowded, but we can get along with each other. Every morning, birds living in the same nest set out to feed together, mostly in groups of 30 to 120, and sometimes groups of different nests meet to form larger groups.
Pink starlings take the way of hunting in flocks, will there be a situation of "more birds and fewer insects"? Will they fight each other over food? No, because clustering is an important survival strategy for them.
Locusts living in arid areas have an innate "camouflage suit", which is what we often call a protective color, and their body color is consistent with the environment and can be integrated with the environment. Not only that, but the body color of the locust will also change with the changes in the surrounding environment. Therefore, when locusts are stationary, they are difficult to detect by predators, which increases the difficulty of preying on pink starlings.
However, locusts, although difficult to detect when stationary, are extremely easy to detect once they are in motion. In order to survive, the pink starling has evolved a set of tricks to deal with locusts. They form large groups, fly close to the ground, and advance in waves. The birds flying in front use the air currents generated during the flight and their calls to disturb the locusts and expose them, and the birds that follow quickly prey on the startled locusts, constantly exchanging spatial positions between the birds before and after to ensure that each bird has the opportunity to prey. In the animal world, if an animal collective relies on frightening prey from a hidden place and then catching and eating it, then as the effective density of prey increases, the time for each individual to wait for the prey to appear will be shortened, and the efficiency of predation will increase accordingly. The pink starling uses this principle, echoing back and forth, and the bee has a sequence, showing the ability to catch locusts. This is the wisdom that nature has given to the pink starling.
Nearly half of the female pink starlings stay in their nests during spawning and hatching, making it difficult to gather in large flocks during this time. So, what about the pink starling when the population size is insufficient and the degree of infestation of locusts is far from enough to meet the needs of foraging? The clever pink starling would go the other way. Just as we are familiar with the symbiotic relationship between cow-backed herons and buffaloes, pink starlings follow large herds of herbivorous wildlife or domestic herds to round up locusts startled by these large animals. In this way, it not only increases its own predatory efficiency, but also effectively controls the number of locusts and protects the forage of large herbivores. If you think about it, it's a wonderful collaboration — the pink starling kills locusts and protects the grass where the large herbivores feed, and the large herbivores help the pink starlings improve their feeding efficiency, which is mutually beneficial.
China has been a country with frequent locust plagues since ancient times, and the scope and extent of the disasters are the highest in the world. Historical records of locust outbreaks abound, such as the Chronicle of Hejian Province.
It is recorded that a locust plague said: "By the nineteenth year of the Yuan Dynasty, more than sixty places in Dadu, Yannan, Yanbei, Hejian, Shandong, and Henan were full of locusts, and the seedlings and crops were exhausted. The hungry catch locusts for food, or dry them and accumulate them; and when they are exhausted, they cannibalize each other. This is the most terrifying description of the locust plague. The locust plague not only caused great harm to agricultural production throughout the ages, but also caused many famines, diseases and even social unrest. In modern times, with the widespread use of pesticides, locust plagues have been contained to some extent. However, in recent years, the locust plague has shown signs of resurgence due to the impact of regional climatic droughts, global warming and the destruction of ecological balances.
The desert grassland area in northern Xinjiang, with a vast area, has been the nomadic grassland of Kazakh herders since ancient times, and some sheltered and abundant desert grasslands are indispensable wintering grounds for herders. However, every spring, locusts are frequent here, and the affected area is nearly 10 million mu. In the case of large chemical locust control, serious environmental pollution and poor effect, people began to pay attention to biological locust control, and pink starlings became the "locust harvester" in the hearts of herders.
In order to protect the pink starlings and allow these "locust harvesters" to better maintain the ecological chain of the grassland, since the 1980s, Xinjiang has begun to use artificial masonry to provide nesting places for pink starlings to attract pink starlings. According to reports, Xinjiang artificially attracts more than 100,000 pink starlings every year, effectively controlling the locust infestation area of tens of millions of mu (1 mu = 0.067 hectares).
How can we achieve the purpose of artificially attracting pink starlings? The researchers found that pink starlings that forage in clusters often come from the same nesting area or several adjacent nesting areas, while stone piles that are too small are not chosen as nesting sites by starlings. Therefore, when artificially attracting, the area of artificial nests and the distance between each nest area should be fully considered to facilitate the formation of large foraging groups. The researchers also found that in addition to the need for a certain amount of drinking water, the pink starling also needs some shallow water areas to bathe, and every evening before returning home, the pink starling will concentrate around the water source for bathing. Therefore, when artificially attracting, the water source should also be fully considered. Why do pink starlings bathe in the evening? The researchers speculate that this is a cleansing act of theirs — washing away parasites from the surface of the body so as not to bring them back to the nest, transmit them to the larvae or spread within the nest.
Pink starlings are instrumental in protecting the ecology of the steppe, but someone has extended a sinful hand to them, and they catch flocks of pink starlings for sale as wild game. Therefore, in order to effectively protect this beneficial bird, we should learn from neighboring Pakistan and list the pink starling as a strictly protected beneficial bird.
Let's take good care of the "locust harvester", the pink starling, and let them guard our grassland.