Rodents Most rodent problems can be prevented with landscape maintenance, good sanitation, and rodent proofing. Sanitation Inspect the school grounds for food sources. Remove edible plants, fallen fruit and nuts, and animal feces. Keep lids on trash cans and close dumpsters at night. Cover the drainage holes in dumpsters with wire mesh to keep rodents out. Remove debris, lumber piles, firewood, trash, and discarded items to reduce shelter for rodents. Trim all vegetation at least 3 feet from all buildings to decrease cover for rodent runways and prevent hidden access to buildings. Break up long stretches of dense vegetation or tall ground cover that allow rodents to travel long distances under cover.

Rodent proofing
Also called exclusion, rodent proofing involves tightening a structure so that rodents cannot get in. A young rat can squeeze through an opening as small as 1/2-inch. Any opening that a pencil can fit through will admit a mouse. Inspect and seal doors, door sweeps, weather-stripping, cracks, gaps, and other openings where rodents may enter a building.

Traps
Trapping is preferable to using rodenticides for controlling rodents on school grounds. Traps can be used in situations where poisonous baits are not allowed; they also avoid the odor problem of rodents dying in inaccessible places. School staff do not need a license to use mechanical traps for rodent control.

Rodents often run along edges, and they routinely follow the same runways. Identifty runways by sprinkling a fine layer of flour or baby powder in suspected areas to observe tracks. Place traps along walls and runways, 6-10 feet apart, especially where objects such as a box or appliance will guide them into the trap. Roof rats and Norway rats usually fear new items in their environment; they avoid them for several
days. Keep all rat traps in place for at least 1 week before moving them.

Traps used for rodent monitoring or management should be checked daily. Traps or other surfaces contaminated with rodent urine or feces should be
properly disinfected or disposed of.

• Baits. The bait depends on the rodent. House mice prefer peanut butter, gum drops stuck to the trigger, or rolled oats or bird seed sprinkled on the trap. When food is abundant, nesting material, such as a cotton ball tied to the trigger, can be effective. Roof rats prefer peanut butter, pieces of fruit, or shelled nuts. For Norway rats, use raw or cooked meat, fish (sardines are excellent), or peanut butter.
• Snap Traps. Both the classic rodent wooden trap and the newer metal clothespin design kill trapped animals quickly. Snap traps should be placed in locked rooms or other areas not accessible to children or in locked, tamperresistant containers securely attached to a surface so that the container cannot be picked up or moved.
• Live traps. Several types of live traps are available. Some catch a single rodent, others reset themselves to capture several. Check live traps regularly to prevent the captured rodents from starving or dying of thirst and creating an odor problem. These traps may be expensive and the live animals must be dealt with. Rodents should not be released to the wild.
• Glue boards are most effective against juvenile mice in dry, dust free areas. Although rat-sized glue boards are available, captured rats can often pull themselves free. Use a tack, a small nail, wire, or double-sided tape to fix
  glue boards to ledges, pipes, or rafters. Do not set them near open flames or above carpet. These traps should not be set where children or domestic animals will come into contact with them. Although they are not hazardous to children, an encounter with a glue board can create a frustrating mess. Clean hands with room-temperature cooking oil. Clean hard surfaces with paint thinner or mineral spirits.

Ultrasound Devices
Ultrasonic devices create a loud noise, above the range of human hearing that is unpleasant to rodents. Rats and mice quickly adapt to the sound by avoiding it. Because the extremely high notes are easily reflected, any object in the area can create a sound shadow. Rodents shift their activity to these low noise shadows. Although the expense of the devices may not
be justified, this behavioral change can be used to guide rodents into traps that are purposefully set in low noise locations.

Chemical control
In situations where trapping alone cannot resolve rodent problems, anticoagulant baits are usually effective. Because rodenticides may be
highly toxic to humans, they should only be used in secure locations and contained in tamper-resistant bait boxes. As with all pesticides, it is a violation of Maine law for unlicensed persons to use rodent poisons in schools. Be sure your pest control professional follows these guidelines for using rodent poisons:

• Use rodent bait stations that are locked and firmly anchored.
• Place bait stations in areas inaccessible to children.
• Place rodenticides in the baffle-protected feeding chamber of the box. Never place bait in the runway.
• Bait stations should be monitored and serviced regularly, and removed promptly when rodents are no longer using them.
• Have your licensed applicator provide a map showing locations of all traps and dates of service.

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