Zebra finches are extremely social in nature and should be kept in pairs to insure their happiness. A pair of zebra finches will often stay in close physical contact at rest or while grooming or preening one another. Zebras nest in wicker type nest or breeder boxes. They will use just about anything for nesting material. You can line the nest for them if you like, but they do a good job on their own.
Zebras are also very protective of their nests.
They will chace any bird that comes too close, even to the point of pulling out feathers on the intruding bird. The breeding process is actually very simple. The mate's sit on a perch next to each other and 'talk' togeather. The male will then hop on the females back and flutter his wings to keep balance. The whole process takes about a minute.