Rat Facts Norway rats are robust rodents that usually weigh about 11 ounces. Their fur is coarse, brownish and scattered with black hair on the upper surfaces. The belly fur is typically gray to yellowish-white, and they sport a naked, scaly tail. Norway rat, rattus norvegicus Rats will eat nearly anything, but they prefer high-quality foods such as fresh grain, livestock feed, and meat. Rats require 1 fluid ounce of water daily when feeding on dry food.
Rats have keen senses of hearing, smell, taste and touch.
Rats have litters of six to 12 young, which are born 21 to 23 days after mating. Young rats are sexually mature in about three months. Breeding occurs mostly in spring and fall. The average female has four to six litters per year. Individuals usually live 12 to 18 months.