Facts | Signs
| Control | Trivia
| Trapping Tips
Back to Rodents
Facts
Wild rats live off man and give nothing beneficial in return. Rats spread disease, damage structures and contaminate food and feed. Rats damage one-fifth of the world's food crop each year. The real damage is in contamination. One pair of rats shed more than one million body hairs each year and a single rat leaves 25,000 droppings in a year.
Rats transmit Murine typhus fever, rat bite fever, salmonellosis or bacterial food poisoning, Weils disease or leptospirosis and trichinosis, melioidosid, brucellosis, tuberculosis, pasteurellosis, rickettsial diseases, and viral diseases such as foot-and-mouth disease. Norway rats can also carry the rabies virus.
The Norway rat and the roof rat are not native North American species. They traveled to the new world with the first explorers. The two species quickly invaded the continent because of their adaptability and fertility. Norway rats are found throughout the United States while roof rats primarily inhabit southeastern, Gulf Coast and southwestern states.
Rats memorize their environment by body and muscle movement alone. They become so engrained by body movements that when objects are removed from their territory, rats will continue to move around them as if the objects where still there.
Successful control depends on proper identification of the different species. Norway and roof rats differ in size, habits, food preferences and regions. Techniques that eliminate one species may not eliminate the other.
Many times roof rats live in the upper stories of buildings, while Norway rats occupy the basement and first floor of the same building.
Rats visit fewer food sites than mice. However, rats eat much more at each site than mice.
Facts | Signs
| Control | Trivia
| Trapping Tips | Top
Signs
Rats constantly leave droppings. Fresh droppings are dark in color and soft in texture, but after three days they harden and lose the dark color.
Rats always travel the same runways and leave "smudge marks" - a buildup of dirt and oil from their fur - along walls, pipes, gnawed openings and beams and rafters.
Rats keep indoor runways, or well-used paths free of cobwebs, debris and dust. Outside, runways appear as narrow paths through vegetation.
Rats make sounds when climbing, clawing and moving.
Footprints and tail drags can be seen in dusty locations. Use tracking dusts such as talcum or flour to determine if rodents are frequenting certain areas.
Gnaw marks are a sure sign of rats. On wood, the older the gnawing, the darker the wood.
If dogs or cats unexplainably get excited, rats are probably moving about in wall voids or ceilings.
Facts | Signs
| Control | Trivia
| Trapping Tips | Top
Control
Find trouble spots: The most important signs of rats are burrows (especially at the edges on concrete slabs and along foundation walls), droppings, tracks, runways, gnaw marks, a foul odor, rat damaged food packages and live or dead rats.
Seal openings that allow rats to enter: Rats can enter any opening that is 1/2 inch wide. Seal any cracks and holes in the foundation walls. All openings where water pipes, electric wires, cables, vents and drain spouts should be tightly sealed. Windows should have tight fitting screens.
Eliminate food sources: Don't store garbage outside in plastic bags. Don't let bird seed accumulate on the ground, or leave pet food outside overnight. Don't leave ripe fruit or vegatables under trees or in the garden to decay. Don't put food scraps in compost piles.
Eliminate rat nesting sites: Remove piles of debris, bricks or boards. Stack lumber and firewood at least 12 inches off the ground so rats cannot burrow underneath. Do not stack any material against the outside walls.
Facts | Signs
| Control | Trivia
| Trapping Tips | Top
Rat Trivia
- The phrase: "Rats are the first to desert a sinking ship" has some basis in fact. In the days of wooden sailing vessels, rats lived in the holds of the ships and would be the first to know if a leak had developed. Ironically, their incessant gnawing in the wood often caused the leaks.
- In some cities, the sewer rat population outnumbers the people population. In Australia, one farmer recorded 28,000 dead mice on his porch after one night's effort to poison them and 70,000 in a wheat field in one afternoon.
- Each year, rodents cause more than one billion dollars in damage in the United States alone.
- Water doesn't stop Norway rats. They can swim as far as 1/2 mile in open water, dive through water plumbing traps and travel in sewer lines, even against strong water currents.
- Unlike the teeth of other mammals, the front incisors of rodents never stop growing, In fact, continuously growing front teeth is a trait shared by all rodents from the tiniest mouse to the largest capybara. By observing captive mice and rats who have nothing to gnaw upon, its been found that these incisors can grow up to five inches per year. Rats constantly gnaw anything softer than their teeth, including lead sheeting, improperly cured concrete, sun dried adobe brick, cinder block, wood and aluminum sheeting.
- The battle to rid dwellings of rodent infestations can certainly seem to be an uphill battle and time seems to favor the rodents. After all, rat and mice bones have been found in the caves where cavemen lived.
- Although water is vital to human health, such is not the case with all rodents. Desert dwelling kangaroo rats, gerbils and prairie dogs never drink water. A chemical process transforms part of their solid food into water.
- A rat can drop down 50 feet without injury. What's more, rats have a 36 inch vertical jump and a 48 inch horizontal jump. Rats can also scale rough vertical surfaces and walk along thin ropes and wires. Roof rats are agile climbers and can shinny the outside of three inch diameter pipes or any size pipe within three inches of a wall. Rats are capable of climbing the inside of vertical pipes that are 1 1/2 to 4 inches in diameter
- Since rats can fit through openings that are as small as 1/2 inch in diameter, it is very difficult to rat-proof a building.
Facts | Signs
| Control | Trivia
| Trapping Tips | Top
Trapping Tips
- Neophobia, or new-object-fear, makes rats extremely cautious about changes in its territory. It takes several days before a rat will accept a new object as part of its territory.
- Trapping has several advantages over poisons, no hazardous chemicals are used, it permits the trapper to see his successes and it eliminates rat death in inaccessible locations which can creat major odor problems.
- The best places to set traps are close to walls, behind objects, in dark corners; anywhere a rat looking for concealment might run. Set traps where rat runways, droppings and gnawings are evident.
- Traps should be set so that the rat, in following its natural course, will pass directly over the trigger. In setting a trap along a wall, the trap should extend from the wall at right angles, with the trigger end nearly touching the wall.
- Rat traps can be used unbaited by placing them directly in the path of rodents with the trigger situated to intercept rats coming from either direction. Expanded treadle-type triggers like the Big Snap-E make this an effiecent method.
- Rats may spring traps without getting caught. If ever a trap is found sprung but with no rat caughrt you can be sure you will never catch it with a trap again.
- Bait for Norway rats should be small pieces of hot dogs, bacon or other prepared meats secured tightly to the trigger. Baits must be replaced every day or so to keep them fresh. Peanut butter also works well.
- An abundance of food makes trapping more difficult. Eliminate as many of the accessible sources of food as possible.
- Human or dead rat odors on traps do not cause a reduction in the catch.