7. Migratory Birds
Many bird species migrate each year. Birds tend to migrate north and south between the area where they breed and the area where they reside during the winter. Migration is driven by the availability of food and is mostly impacted by humans that hunt.
Birds use cues from the sun and stars, as well as the Earth’s magnetic field to navigate their way around the globe. Scientists estimate that dramatic climate changes are mainly affecting the timing of migration for birds. This is also contributing to the decline in bird populations as well as breeding. Several conservationist groups have worked hard to protect the movement of birds in North America.