Someone believes that it is the smell and others thinks that earth induction. Not only the migratory birds, but dove can remember their way to home.
Primarily migratory waterfowl, some mammals, some birds and Monarch butterflies are some examples of animals that return to the same place every year.
the migratory routes are from California beaches too Japan and back every year
Because most are migratory, you have to look for them in different locations at different times of the year.
Birds such as wagtails, brown shrikes, pintails, ruddy shelducks, garganey birds, shovellors, mallards, herring gulls are not seen throughout the year because they have come from some parts of the globe for a certain period of time. These birds are what we called migratory birds. The best place to see such migratory birds are certain wetland or riverine areas. The most striking feature of the migratory birds is that they come in flocks in enormous numbers and often swarmed the areas they visited. Most of the migratory birds in India come from very far off places in the northern part of the globe, such as the palaerctic regions, across the high mountain ranges of the great Himalayas. Majority of the migratory birds coming to India are ducks, geese and cranes. Migratory ducks fly in an enchanting V-formation; maybe they have to save as much energy as they can because they have to travel a long distance during their migration
Resident birds stay in one place all year round. Migratory birds fly to different countries at different seasons, e.g. swallows spend the summer in northern Europe but the winter in Africa, and Whooper swans go to Iceland for the summer and come to Britain in the winter.
Hummingbirds and barn swallows are migratory birds, moving to different locations during different seasons to find food and suitable habitats. Blue jays, on the other hand, are non-migratory birds that typically reside in one area year-round.
Many of the oranges grown in Florida and California are picked by migrant workers.
Geese because they migrate every year in giant groups.
A migratory bird is as it sounds; a bird that migrates threw your area. You may see this bird for a period of time and then it will migrate back. A resident bird is a bird that stays in your area all year round; this is his home and there are plenty of them in the area.
Resident birds stay in one place all year round. Migratory birds fly to different countries at different seasons, e.g. swallows spend the summer in northern Europe but the winter in Africa, and Whooper swans go to Iceland for the summer and come to Britain in the winter.
By providing shelter and protection we can help the birds in our community. The migratory words nest and breed at the same place year after year. So we should not disturb their places of nesting. Instead, we should try to provide all the birds a natural environment, as far as possible.
About 1 billion birds are killed in the US every year so possibly, 5 to 10 billion birds per year. As for per day, possibly 1 to 10,000 birds.