AP BIOLOGY

Detailed explanation-1: -Migratory birds travel long distances during winters, majorly due to the cold weather and lack of food in their region. They travel to places which are warmer and have abundant availability of food. Once the winter season comes to an end, they return back home.

Detailed explanation-2: -Avian migration is a natural miracle. Migratory birds fly hundreds and thousands of kilometres to find the best ecological conditions and habitats for feeding, breeding and raising their young. When conditions at breeding sites become unfavourable, it is time to fly to regions where conditions are better.

Detailed explanation-3: -Birds mainly migrate for breeding or in search of food due to environmental factors like weather, season etc. Animals migrate in search for suitable shelter, food and suitable place for breeding.

Detailed explanation-4: -Long-distance migrants typically move from breeding ranges in the United States and Canada to wintering grounds in Central and South America. Despite the arduous journeys involved, long-distance migration is a feature of some 350 species of North American birds.