Rat Management
Mouse Managment
(click here for a
free evaluation of your property)
Rat Management
The common brown rat (Rattus norvegicus -- also called the Norway
rat or sewer rat) is a destructive animal pest found in and around
towns and farms. These rodents eat and contaminate large amounts
of feed, damage structures by their gnawing and burrowing and
may spread diseases that affect livestock and people.
Recognizing Rat Infestations
The presence of rats can be detected by droppings or evidence
of fresh gnawing. Tracks can be seen in mud and on dusty surfaces.
Runways and burrows may be found next to buildings, along fences,
and under low vegetation and debris.
Rat Facts
Norway rats are fairly husky, brownish rodents that weigh about
11 ounces. They are about 13 to 18 inches long including the 6
to 8 1/2 inch tail. Their fur is coarse and mostly brown with
scattered black on the upper surfaces. The underside is typically
grey to yellowish-white.
Rats will eat nearly any type of food, but they prefer high-quality
foods such as meat and fresh grain. Rats require 1/2 to 1 fluid
ounce of water daily when feeding on dry food. Rats have keen
taste, hearing, and sense of smell. They will climb to find food
or shelter, and they can gain entrance to a building through any
opening larger than 1/2 inch across.
Rats have litters of 6 to 12 young, which are born 21 to 23 days
after mating. Young rats reach reproductive maturity in about
three months. Breeding is most active in spring and fall. The
average female has 4 to 6 litters per year. Rats can live for
up to 18 months, but most die before they are one year old.
back to the top
Rat Control
Sanitation: Poor sanitation and the presence of garbage allows rats to exist in residential areas. Good sanitation will effectively limit the number of rats that can survive in and around the home. This involves good housekeeping, proper storage and handling of food materials and refuse and elimination of rodent harborage (shelter). Outside dog pens must be properly maintained, to reduce potential rat problems.
On farms where food grains are handled and stored, or where livestock
are housed and fed, it is difficult to remove all food that rats
can use. In such situations, paying particular attention to removing
shelter that rats can use for hiding, resting, and nesting is
valuable in reducing rat numbers.
Warehouses, grain mills, and silos are especially vulnerable
to rodent infestation. Store bulk foods in rodent-proof buildings,
rooms, or containers whenever possible. Stack sacked food on pallets
with adequate space left around and under stored articles to allow
inspection for signs of rats. Good sanitary practices will not
eliminate rats under all conditions, but will make the environment
less suitable for them to thrive.
Rat-Proof Construction: The most successful and permanent form of rat control is to "build them out" by making their access to structures impossible. Ideally, all places where food is stored, processed or used should be rodent-proof. Store bulk foods, bird seed, and dry pet food in metal trash cans or similar containers.
Seal any openings larger than 1/4 inch to exclude both rats and
mice. Openings where utilities enter buildings should be sealed
tightly with metal or concrete. Equip floor drains and sewer pipes
with tight-fitting grates having openings less than 1/4 inch in
diameter. Doors, windows and screens should fit tightly. It may
be necessary to cover edges with sheet metal to prevent gnawing.
back to the top
Traps: Trapping is an effective method of control. It is the preferred method in homes, garages, and other structures where only a few rats are present. Trapping has several advantages: 1) it does not rely on inherently hazardous poisons; 2) it permits the user to determine if the rat was killed and 3) it allows for disposal of rat carcasses, thereby eliminating odor problems which may occur when poisoning is done within the buildings.
A simple, inexpensive wood-based snap trap is available in most
hardware and farm supply stores. Wire cage traps are more expensive
but somewhat more successful than snap traps. Bait traps with
peanut butter or a small piece of hot dog, bacon, or nutmeat tied
securely to the trigger. The trigger should be set lightly so
that it will spring easily. Set traps close to walls, behind objects,
in dark corners, and in places where rat activity is seen. Place
the traps so that rats, following their natural course of travel
(usually close to a wall), will pass directly over the trigger.
Use enough traps to make the campaign short and decisive. Leaving
traps unset until the bait has been taken at least once reduces
the chances of rats becoming trap-shy.
Using Poison Baits (Rodenticides): Rodenticides are poisons that kill rodents. They are available as either non-anticoagulants or as anticoagulants. They can be purchased in hardware stores, feed stores, discount stores, garden centers, and other places where pesticides are sold.
The non-anticoagulants cause death either via the nervous system
or via the release of calcium into the bloodstream. Anticoagulants
cause death as a result of internal bleeding, which occurs as
the animal's blood loses its clotting ability and capillaries
are destroyed. The active ingredients are used at low levels,
so bait shyness does not occur when using properly formulated
baits.
Most of these baits kill rats only after they are fed on for
a number of days. The exceptions are brodifacoum or bromadiolone,
which are capable of causing death after a single feeding. However,
rats do not die for several days. When anticoagulant baits are
used, fresh bait must be made available to rats continuously as
long as feeding occurs. Depending on the number of rats, this
may require up to three weeks.
back to the top
Bait Selection and Placement: Baits are available in several types. Grain baits in a meal or pelleted form are often available in bulk or packaged in small plastic, cellophane, or paper packets. These "place packs" keep baits fresh and make it easy to place baits into burrows, walls, or other locations. Rats will readily gnaw into these bags to get at an acceptable bait. Block style baits are also very effective for most baiting situations.
Use of tamper-resistant bait boxes provides a safeguard to people,
pets, and other animals. Place bait boxes next to the walls, with
the openings close to the wall, or in other places where rats
are active. When possible, secure the bait station to a fixed
object to prevent it from being moved. Label all bait boxes clearly
with the words "Caution--Rat Bait" or another similar
warning.
Sound and Electronic Devices: Rats quickly become accustomed to regularly repeated sounds. Ultrasonic sounds, those above the range of human hearing, have very limited use because they are directional and do not penetrate behind objects. Also, they quickly lose their intensity with distance. There is little evidence that sound of any type will drive established rats from buildings or otherwise give adequate control.
Predators and Biological Control: Although house cats, some dogs, and other predators kill rats, they do not usually give effective rat control. It is not uncommon to find rats living in very close association with dogs and cats. Rats frequently live beneath a doghouse and soon learn they can feed on the dog's food when he is absent or asleep. Many rat problems around homes can be related to the keeping of pets, on the other hand, some cats and dog breeds will reduce existing rat problems.
back to the top
(click here for a
free evaluation of your property)
Mouse Management
The house mouse (Mus musculus) is considered one of the most troublesome
and economically important rodents in the United States. House
mice live and thrive under a variety of conditions. They are found
in and around homes and farms as well as in open fields and agricultural
lands. House mice consume and contaminate food meant for humans,
livestock, or other animals. They cause damage to structures and
property, and they may transmit diseases such as salmonellosis
(food poisoning).
Recognizing Mouse Infestations
Droppings, fresh gnawing, and tracks indicate areas where mice
are active. Mouse nests, made from fine shredded paper or other
fibrous material, are often found in sheltered locations. House
mice have a characteristic musky odor that identifies their presence.
Mice are occasionally seen during daylight hours.
House Mouse Facts
House mice are non-descript, brownish rodents with relatively
large ears and small eyes. They weigh about 1/2 ounce and are
usually light brownish to light grayish. An adult is about 5 1/2
to 7 1/2 inches long, including the 3- to 4-inch tail.
Although house mice usually feed on cereal grains, they will
eat many kinds of food. They are sporadic feeders, nibbling bits
of food here and there. Mice have keen senses of taste, hearing,
smell, and touch. They are excellent climbers and can run up any
rough vertical surface. They will run horizontally along wire
cables or ropes and can jump up 13 inches from the floor onto
a flat surface. Mice can squeeze through openings slightly larger
than 1/4 inch in diameter.
In a single year, a female may have five to ten litters of usually
five or six young each. Young are born 19 to 21 days after mating,
and they reach reproductive maturity in six to ten weeks. The
life span of a mouse is about nine to twelve months.
back to the top
House Mouse Control
Effective control involves three aspects: sanitation, mouse proof
construction and population reduction. The first two are useful
as preventive measures. When a mouse infestation already exists,
some form of population reduction is almost always necessary.
Reduction techniques include trapping and poisoning.
Sanitation: Because mice can survive in very small areas with limited amounts of food and shelter, it is almost impossible to eliminate them, particularly on farms. Most buildings in which food is stored, handled, or used will support house mice if not mouse-proofed, no matter how good the sanitation. Although good sanitation will seldom eliminate mice, poor sanitation is sure to attract them and will permit them to thrive in greater abundance. Good sanitation will also reduce food and shelter for existing mice and in turn make the baits and traps more effective. Pay particular attention to eliminating places where mice can find shelter. If they have few places to rest, hide, or build nests and rear young, they cannot survive in large numbers.
Mouse-Proof Construction: The most successful and permanent form of house mouse control is to "build them out" by eliminating all openings through which they can enter a structure. All places where food is stored, processed, or used should be made mouse-proof. Dried grain and meat products should be stored in glass jars, metal canisters, re-sealable coffee cans, or other air tight containers.
Seal any openings larger than 1/4 inch to exclude mice. Steel
wool mixed with caulking compound makes a good plug. Patching
material needs to be smooth on the surface to prevent mice from
pulling out or chewing through the patching compound. Seal cracks
and openings in building foundations and openings for water pipes,
vents and utilities tightly with metal or concrete. Doors, windows,
and screens should fit tightly. It may be necessary to cover the
edges with metal to prevent gnawing. Plastic sheeting or screen,
wood, rubber, or other gnawable materials are unsuitable for plugging
holes used by mice.
back to the top
Traps: Trapping is an effective control method. It is the preferred method in homes, garages, and other structures where only a few mice are present. Trapping has several advantages: 1) it does not rely on inherently hazardous poisons; 2) it permits the user to confirm that the mouse has been killed and 3) it allows for disposal of the mouse carcasses, thereby eliminating dead mouse odors which may occur when poisoning is done within buildings.
The simple, inexpensive wood-based snap trap is effective and
can be purchased in most hardware and grocery stores. Bait traps
with peanut butter, chocolate candy, dried fruit, or a small piece
of bacon tied securely to the trigger. Set them so that the trigger
is sensitive and will spring easily. Leaving traps baited but
unset until the bait has been taken at least once reduces the
chance of creating trap-shy mice.
Multiple-capture live traps for mice such as the Victor Tin Cat®
and the Ketch-All®, are also available in some hardware and
feed stores. Set traps close to walls, behind objects, in dark
corners, and in places where evidence of mouse activity is seen.
Place them so that mice will pass directly over the triggers as
they follow the natural course of travel, usually close to a wall.
Traps can be set on ledges or on top of pallets of stored materials
if mice are active in such locations. Use enough traps to make
the campaign short and decisive. Mice seldom venture far from
their shelter and food supply, so space traps no more than about
10 feet apart in areas where mice are active.
An alternative to traps are glue boards, which catch and hold
mice attempting to cross them in much the same way flypaper catches
flies. Place glue boards along walls where mice travel. Two or
three glue boards placed side-by side will be more effective than
individual boards. Do not use them where children, pets, or desirable
wildlife can contact them. Glue boards can be placed inside bait
stations in exposed locations. Glue boards lose their effectiveness
in dusty areas unless covered, and extremes of temperature also
may affect the tackiness of the adhesive.
back to the top
Using Poison Baits (Rodenticides): Rodenticides are poisons that kill rodents. They are available as either non anticoagulants or as anticoagulants. They can be purchased in hardware stores, feed stores, discount stores, garden centers, and other places where pesticides are sold.
The non-anticoagulants cause death either via the nervous system
or via the release of calcium into the bloodstream. Anticoagulants
cause death as a result of internal bleeding, which occurs as
the animal's blood loses its clotting ability and capillaries
are destroyed. The active ingredients are used at very low levels,
so bait shyness does not occur when using properly formulated
baits.
Most of these baits cause death only after they are fed on for
a number of days. The exceptions are baits containing brodifacoum
or bromadiolone. These baits can cause death following a single
feeding, although the mouse does not die for several days.
When rodenticides are used, fresh bait must be available continuously
until mice stop feeding. Depending on the number of mice, this
may require up to three weeks.
Bait Selection and Placement: Baits are available in several
forms. Grain baits in a meal or pelleted form are available in
small plastic, cellophane, or paper packets. These sealed "place
packs" keep bait fresh and make it easy to place the baits
in burrows, walls, or other locations. Mice gnaw into the packet
to feed on the bait. Block style baits are also very effective
for most baiting situations.
Proper placement of baits and the distance between placements
is important. Space bait placements no farther than 10 feet apart
and preferably closer. For effective control, baits or traps must
be located where mice are living.
Use of tamper-resistant bait stations provides a safeguard to
people, pets, and other animals. Place bait stations next to walls
with the openings close to the wall, or in other places where
mice are active. When possible, secure the bait station to a fixed
object to prevent it from being moved. Clearly label all bait
stations "Caution‹Mouse Bait" as a safety precaution.
back to the top
Sound and Electronic Devices: Although mice are easily frightened by strange or unfamiliar noises, they quickly become accustomed to regularly repeated sounds and are often found living in grain mills and factories. Ultrasonic sounds, those above the range of human hearing have very limited use in rodent control because they are directional and do not penetrate behind objects. Also, they lose their intensity quickly with distance. There is little evidence that sound of any type will drive established mice or rats from buildings.
Predators: Although cats, dogs, and other predators may kill mice, they do not give effective control in most circumstances. It is not uncommon to find rodents living in very close association with dogs and cats. Mice and rats may obtain much of their diet from the pet's dish or from what pets spill. In barns, stables, and other areas where grain based feed is always available to mice, some cats and dog breeds may help reduce mice populations.
back to the top
