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The Basics Of Bird Migration

•  Reasons for bird migration

Birds migrate to different areas other than the ones in which they live, due to several reasons, including the following:

1- searching for food

Food scarcity is one of the most important motives for the migration of most bird species so that if birds remained in the same topics throughout the year, food would become scarce, and reproduction would decrease, but with the renewal of food sources in the northern part every spring, millions of birds would migrate to those areas  To take advantage of their abundance, and when food supplies run low in the fall, birds return to the tropics where food sources have been replenished in the meantime.

2- Preserving the offspring

 Birds have developed over thousands of years different patterns, times, and destinations of migration around the world, which helped them take advantage of the different and appropriate conditions for raising their young, and increase the chance of obtaining healthy offspring, and the appropriate conditions for upbringing differ according to different types of birds and also depend on several factors.

3- Climate 

Birds have evolved different types of plumage to adapt to climatic differences that affect migration, for example, many birds leave breeding grounds in the Arctic when temperatures begin to drop because they need higher temperatures to be able to survive, similarly, areas may be  Hot administration is a harsh environment for raising young, and it is advisable to lay eggs north in cooler areas.

4- Surviving predators 

 Birds move to various locations where predators cannot reach because areas with rich food supplies throughout the year attract huge numbers of predators that jeopardize bird nests. To put it another way, to avoid them and to give their young a better chance of maturation, such as offshore rocky islands and coastal cliffs.

5- Disease

 Birds migrate to different places to combat diseases and parasites that are more vulnerable to them if they gather and stay in one natural habitat.

• bird migration patterns

The following is a list of bird migratory patterns based on their diversity:

1. Resident birds are birds that never migrate, and have the ability to find an adequate supply of food all year round.
2. Birds migrate short distances, such as migrating from a higher place to a place lower than the foot of a mountain.
3. Birds migrate medium distances, such as migration from one state to several states.
4. Birds migrate long distances, such as birds that migrate from breeding grounds in Canada and the United States to wintering areas in South and Central America.

• Times of bird migration

 Each type of bird migrates at a certain time of the year and a certain time of the day.  Available in summer, experiments show that longer day stimulates migration.

• Protection of migratory birds 

 In addition to the fact that the migration of birds is an arduous and tiring journey, but it is also dangerous due to the lack of safety factors during the journey, and to make it safer, the following steps can be followed:

1. 
   Extinguishing unnecessary lights in homes and establishments in general; The bright light distracts migratory birds, crashing into buildings and dying.
2. Protecting migratory birds from cats, and trying to keep house cats indoors or in their own homes as much as possible, as one cat is able to kill 55 birds.
3. Providing food for birds in home gardens during the spring migration.
4. Create a tree habitat for birds in your garden, leaving tree trunks and fallen branches in place to house insects that birds feed on.
5. Minimize plastic waste. Birds ingesting plastic can cause serious injury or death.
6.  Supporting bird-friendly legislation, and spreading awareness in the community.
7. Getting rid of insecticides in home gardens, which kill insects that birds rely on for food, and making sure that these pesticides do not reach the waterways from which birds drink.
8. Compliance with fishing laws.

• How do birds find their way during migration?

Birds usually take the same path each year at the time of migration, because these paths are linked to important stopping sites that provide the food supplies necessary for the survival of these birds, but birds can generally obtain path information in several ways, including the following:

1. The sun and the stars.
2. sunset site.
3. Earth's magnetic field sensor.
4. Landmarks seen during the day.
5. Homing pigeons use their sense of smell to help them migrate.

• Why is the migration of birds in the shape of the letter v?

During their study, scientists found that the V-shaped migration of birds serves two main purposes; They are as follows:

1- Conserve energy as much as possible

As each bird flies over the one in front of it to reduce wind resistance, and all the birds take turns on the front to comfort each other; Tired birds retreat to the front, so studies have found that birds that fly solo beat their wings more frequently and have higher heart rates than birds that migrate in groups.

2- Make it easy to keep track of birds in the group

Flying in a V-shaped group helps with communication and coordination within the group, so each bird in the group can be easily tracked.