Other forms: breeding grounds
Many wild animals return to the same place every year to breed: this is called a breeding ground.
Animals that migrate may travel hundreds of miles over the course of a year, coming back to a breeding ground to reproduce and give birth to babies. Sea turtles crawl onto the beach, their breeding ground, to lay eggs; and polar bears use breeding grounds on solidly frozen pack ice. You can also use the phrase in a figurative way, to mean a rich or fertile environment — you might call Austin, Texas a breeding ground for new music.