20 17 what is the date of world migratory bird day: may 13?

In nature, many birds have the characteristics of seasonal migration along latitude. In summer, these birds breed in temperate regions with higher latitudes and spend the winter in tropical regions with lower latitudes. These birds that migrate north and south with the seasons are called migratory birds. Then let the World Festival Encyclopedia introduce the date of 20 17 World Migratory Birds Day, calling for the protection of migratory birds and their living environment.

Q: When is the 20 17 World Migratory Bird Day? A: Every year, the second Saturday in May is the World Migratory Bird Day, and the World Migratory Bird Day in 20 17 is May 13.

The second Saturday of May is World Migratory Birds Day every year. This annual activity is jointly sponsored by the Agreement on Non-Eurasian Migratory Waterbirds (AEWA) and the Global Convention on Migratory Species (CMS). These two international treaties are administered and implemented by the United Nations Environment Programme (UNEP).

According to the United Nations Environment Programme, birds are one of the most accurate representatives of a wide range of biodiversity. Many endangered animal and plant species live in many important bird habitats. In the annual migration cycle, migratory birds cross a large area from permafrost and tropical areas. By protecting migratory birds and their living environment, human beings can better protect biodiversity.

Expansion and extension: reasons for migratory birds migration There are two reasons for migratory birds to migrate every year: one is to find food to breed, and the other is to avoid cold weather and generally migrate to tropical areas.

In temperate regions, the days are long and the nights are short in summer, so birds have longer time to feed and nurse their young. In addition, the number of insects in temperate regions in summer is more abundant than that in tropical regions, with fewer natural enemies and relatively lower pressure. However, the cold weather in winter often leads to food shortage.

In tropical areas, although birds will face fierce competition in nesting sites and food resources in summer breeding season, and the predation pressure of natural enemies is also relatively high, the climate is mild after winter, and the food resources in winter are much richer than those in temperate areas.

Migratory birds breed in temperate zone in summer and tropical zone in winter, and both places have advantages. So in that case, why don't all birds become migratory birds? The answer is that immigrants must pay the price. For example, the migration process needs to consume a lot of energy, may encounter bad weather, the migration direction is wrongly positioned, and it is necessary to adapt to an unfamiliar new environment and compete for resources with other migratory birds and resident birds in the region.

At the same time, when all birds adopt the behavior pattern of large income (migration), the competition will become greater, and the behavior pattern of small income (that is, no migration) will become relatively favorable. Therefore, different behavior patterns will exist in evolution, and an evolutionary stability strategy (ESS) will be achieved. This is why some birds migrate and some birds don't.

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