Good aquaculture procedures for animal and pest control involve exclusion, control, and eradication measures where appropriate. In pond production, the more significant animal vectors are birds and four-legged animals. For bird control, a combination of scare tactics and lethal depredation techniques are often the most effective (depredation requires permits, usually from a state game and fish agency). Terrestrial animal control usually incorporates facility fencing, and sometimes pond fencing For rodents, perimeter traps close to habitat may be effective. Recirculating aquaculture systems are typically housed in buildings, so the structure itself is usually effective to exclude most birds and terrestrial animals. However, rodents, roaches, and other pests tend to be more concentrated around RAS structures due to the attraction of feed and fish. Therefore, effective plans to operate and maintain rodent traps are important, as is proper chemical pest control for roaches and such. Great care must be taken with chemical control to assure that chemicals or sprays do not come in contact with feed, water, or production equipment. Emphasis on pest control is required in the feed-storage area