Final answer:
Cranes migrate to summer grounds for breeding and food sources, and to winter grounds for milder climates that ensure their survival with sufficient food and protection, but they do not hibernate.
Step-by-step explanation:
Cranes are among the various species of animals that exhibit migration, an innate behavior that involves the seasonal movement from one area to another, typically in response to changes in temperature, food availability, and the need for suitable breeding grounds. In the summer, cranes migrate to breeding grounds, where they not only find mates but also have access to abundant food sources necessary for raising their young. In contrast, during the winter, cranes travel to areas that offer milder climates, which are critical for their survival, as these areas provide sufficient food and sometimes a respite from extreme cold. Their winter habitats might also offer some protection from predators and other threats. It is not correct to say that cranes hibernate during the winter; instead, they remain active but seek out environments that are more conducive to their survival during the colder months.