RODENTS

INTRODUCTION OF RODENTS

- Are mammals of the order Rodentia such as a mouse, rat, squirrel or beaver 

- Characterized by a single pair of continuously growing incisors  in each of the upper and lower jaws.

PROBLEMS

• SPREAD SERIOUS DISEASES including salmonellosis (food poisoning), leptospirosis, rickettsialpox and lymphocytic choriomeningitis

• CARRY FLEAS, ticks and other ectoparasites, potentially spread disease, such as bubonic plague.

• CONSUME OR CONTAMINATE about 20 percent of the world's food supply.

COMMENSAL RODENTS

1. They destroy property, frighten people and compete with human for food.
2. Rats plague many store owners and farmers.
3. Undesirable in feed and seed stores because destroy the seed, corn etc.
4. Undesirable in poultry houses and bird farms.
5. Destroy and contaminate structure as well as harm young birds and chicks.

TYPES OF RATS

NORWAY RATS ( RATTUS NORVEGIUS)

• The Norway Rat is a large rodent, growing up to 18 inches long, including the tail.
•  Males are larger than females. 
• The rat's color is grayish-brown with a pale gray belly. Ears and tail are bald.
• Norway Rats are found anywhere there are people. 
• This rat, originally from Asia, has followed people around the world, and it is now found throughout the United States. Common places Norway Rats live are ditches, basements, sewers, old buildings, barns, dumps, woods, fields, ponds, and marshes.
• Norway Rats are almost always found near water. 
• They are very good swimmers and climbers.
• Norway Rats always live in large groups in burrows. 
• Rat burrows are actually a large network of passageways, runways, and chambers.
• A rat pack hunts together, breeds together, and defends the burrow together.
• Rats breed often and each female may have seven litters in a year. Each litter has 2 to 14 young. 
• A rat is full grown in about four weeks. 
• Rat nests are made of leaves, twigs, and trash.
• Norway Rats only live two or three years.
• Rats have many predators, including snakes, fox, skunks, weasels, owls, hawks, cats, and dogs. 
• These predators are very important since they control rat populations.
• Norway Rats disperse seeds when they eat them and poop them out in new places. This helps plants spread.
• Rats also help plants grow by aerating soil.
• This means they put oxygen into the soil when they dig. This makes plants healthier in those areas.Rats communicate with one another using squeaks, whistles, and chirps.

ROOF RATS ( RATTUS RATTUS )

• The roof rat is dark brown to black in color and measures 13 to 18 inches in length including tail. 
• They weigh 5-9 ounces, are slender, and their ears are large and nearly hairless. Their droppings are long and cylindrical.

Understanding Roof Rat Behavior

Common signs of roof rat activity

• Visual sightings on power lines, trees, bushes, patios, roofs, etc.
• Hollowed citrus and other fruit
• Rat droppings
• Noises in the attic and walls
• Gnawing sounds and gnaw marks around roof eaves
• Damage to plastics and coverings on electrical wires
• Unsettled pets 

Places roof rats have been found

• They have been found in swimming pools, laundry rooms, attics, garages, and patios.
• They’ve been seen on power lines in the alleys.
• Roof rats spend 90 percent of their life 4 feet or more off the ground.

Roof rat traveling patterns

• Roof rats are strongly arboreal (tree inhabitants) and travel along power lines to trees, oleanders, vines, and roofs.
• They can climb up brick, concrete block and other rough surfaces.
• They can jump 2 feet up and 4 feet horizontally (double the horizontal distance if they are jumping from a height).
• Ground covers and compost bins also provide safe travel routes and nests.
• During twilight and nighttime hours, within a territory 200 to 300 feet from their daytime nesting locations.
• They thrive in cool weather and are most active from November through May.

How roof rats enter homes

• They enter homes, sheds, garages and other structures through any opening larger than a nickel, looking for places safe from predators and good for nesting.
• They may follow pipes down from the attic, gnaw through drywall, to access structures
• They may chew through wood, plastic, aluminum siding, sheet rock, and soft metals to gain access to interiors.
• Attics provide a safe refuge, a nesting place for their young and routes into the home below.

What roof rats eat and drink

They love to eat all types of citrus and other fruits, and nuts, including:

• Lemons
• Limes
• Grapefruits
• Oranges (including ornamental oranges)
• Tangelos
• Tangerines
• Figs
• Pomegranates
• Palm fruit, including Queen Palm fruit, especially in summer when citrus is not available
• Nectarines
• Peaches
• All nut fruits like walnuts, almonds and pecans
• Rats do not have a discerning taste for fruit like humans
• Fruit can be green (unripe) or even rotted
• Rats eat fruit more for their water content than for food sustenance

They’ll also eat:

• Bird seed (both in feeders and stored in bags)
• Dog and cat food (left outside after dark are favorites)
• Stored grains
• Vegetables in your garden
• Insects
• Lizards
• Tree bark
• Soap
• Paper
• Animal and taxidermy hides
• Beeswax and candle wax

Water sources include:

• Leaky faucets
• Leaky sprinkler heads
• Leaky irrigation boxes
• Bird baths
• Water fountains
• Ornamental ponds
• Irrigation lines
• Air conditioner condensation drip lines
• Saucers under potted plants
• Pet water dishes

HOUSE MICE ( MUS MUSCULUS )

APPEARANCE

• House mice are covered in short hair that is light brown or gray to black in color, with lighter bellies. 
• Their ears and tail also bear hair, although much less than their bodies.
•  Adult mice weigh approximately 12 to 30 grams and can grow up to 20 cm from the nose to the tip of the tail. 
• Droppings are rod-shaped and pointed on both ends.

BEHAVIOR, DIET, HABIT

• The house mouse makes its home in farm fields, grassy and wooded areas, building nests in areas that are dark and protected from the elements and close to a readily available food source.
• Very inquisitive in nature, the house mouse will spend the day roaming its territory, exploring anything new or out of the ordinary.
•  When available, the house mouse prefers seeds and nuts in its diet, but this opportunistic feeder will eat almost anything available.
• When the temperatures outside begin to drop, house mice, since they don’t hibernate, begin searching for a warmer place to live. 
• Often attracted by the smell of food and the warmth of a structure, the house mouse can use any opening, such as utility lines, pipe openings, and gaps beneath doors, to gain entry into a home.

REPRODUCTION

• The house mouse is known for its ability to reproduce very quickly. 
• A single female is capable of producing up to eight litters per year with an average of six pups per litter. 
• After a 21-day pregnancy, these house mouse pups are born naked, blind and dependent upon their mother for everything. 
• At about 21 days the young are weaned from their mother and may begin to take short trips away from the nest to explore their surroundings. 
• Most mice reach sexual maturity at about 35 days of age and begin mating when they are six weeks old.

SIGNS OF RAT'S PRESENCE

1. Faeces
2. Footprints
3. Runway
4. Smears
5. Bitemarks
6. Smears
7. Burrows
8. Smell
9. Urine
10. Live rat
11. Carcass
12. Nest

RODENTS AND HUMAN HEALTH

DISEASE RELATED TO RODENTS :

• Hantavirus Pulmonary Syndrome
• Haemorrhagic Fever
• Leptospirosis
• Human Lymphocyctic choriomeningitis 
• Plague
• Rat- Bite-Fever
• Salmonellosis
• Murine Typhus

RODENT CONTROL MEASURES

- Eliminating sources of food

- Eliminating breeding and nest places

- Rat-proofing buildings and other structures

- Killing them

references : rodents