Chinese people never eat swallows. Why are the number of swallows still declining?

Chinese people even dare to eat scorpions, spiders, and centipedes, but it is rare to hear of people eating swallows and goldfish, because these two creatures have been considered auspicious omens since ancient times, and goldfish are in Feng Shui. The bird is considered to have the effect of gathering wealth and reducing evil spirits, while the swallow is considered an auspicious bird. Whoever has swallows to build nests shows that the geographical location and Feng Shui pattern of the house are good, and swallows are a beneficial bird. They can eliminate pests such as mosquitoes, flies, and locusts. There were no pesticides and chemical fertilizers in ancient farmland, and swallows eliminated pests. It is equivalent to feeding the farmers, so humans and swallows have always lived in harmony.

There is a saying that goes well: "I don't kill Boren, but Boren died because of me." Although humans do not eat swallows, human behavior has led to a significant reduction in the number of swallows.

The biggest difficulty faced by swallows is the problem of housing. In the past, every spring, swallows would go to the river to find some moist clay, smear the clay under the eaves outside the door, and then wait until the soil is dry. Add some branches and plant fibers to enhance the stability, and add some feathers to enhance the warmth effect, and the swallow's nest is piled up. With the development of urbanization, demolitions are taking place all over the country. Old-fashioned rural houses suitable for swallows to nest have disappeared. Swallows' nests must be attached to red brick walls and lime walls, but the walls of demolished houses are all covered with ceramic tiles and cement. Or painted walls. Swallows' nests cannot be built on such walls. Even if they are built, there is a high probability that the entire nest will collapse and fall to the ground, eventually causing the swallow cubs to fall to death.

A large number of fields have been used for real estate development, making it very difficult for swallows to hunt in cities. Therefore, swallows can only fly to rural mountainous areas, and cities are no longer suitable for swallows to live. New houses in rural areas do not have many structures suitable for swallows to build nests, such as citrons, beams, and trusses. Such structures can only be seen in some remote mountainous areas; many rural houses also have closed doors on the first and second floors. Aluminum alloy doors and windows may block the passage for swallows to build nests; for hygienic reasons, many families will even sweep away the nests under construction with brooms, destroy the swallows' homes, and further "destroy" the swallows.

Another major factor affecting the number of swallows is food. We have all learned in biology that if swallows feed on pests and the number of a large number of pests decreases, then the number of swallows must decrease. In the past 20 years, large amounts of pesticides have been sprayed on farmland, and many pests have been artificially killed. Swallows are no longer needed to help catch pests. Swallows are starved to death due to lack of food. Moreover, most pesticides and toxic substances are not easily excreted through metabolism and will accumulate in the body. With bioaccumulation, the insects eaten by swallows may contain higher concentrations of pesticides, which also indirectly kills the swallows.

Moreover, many rural areas now no longer plant crops alone as before. People who have the conditions have begun to use greenhouses to cultivate crops. Of course, swallows cannot fly into the greenhouses to hunt, and some farmlands have begun to raise fish. Shrimp farming, some farmland is planted with turf, has become diversified, and the food swallows can catch is even less. Importing food from abroad and taking land for development domestically have no place for swallows, and their numbers will naturally decrease.

The last possible reason is the deterioration of the natural environment, resulting in a decrease in the number of swallows. Swallows are migratory birds and go south every winter to live on islands in Bangkok, Thailand, the Philippines and Australia. Many swallows need to cross the ocean and overcome their own exhaustion to reach their destinations. With global warming, there are more uncertain factors in the ocean and the natural environment is deteriorating. Swallows may fall into the sea and become dinner for fish. Many swallows die on the way across the ocean.