RATS
Rattus
INTRODUCTION
The most common rodents (rats & mice) our residents encounter
are, what is referred to as, commensal rodents. These rodents
have become dependent on humans for survival. They are not
native to the states, but have become well established here. There are three types of commensal rodents: the roof rat, house
mouse, and the norway rat. Rodents are normally nocturnal and
of various sizes with long tails. Typically the rat is distinguished
from a mouse by size. In general, the larger of the two is
frequently referred to as a rat while the smaller referred to as a
mouse. However, scientifically, these two terms are not specific.
Rats are frequently blamed for damaging food and other goods but
most importantly rats are considered to be established vectors because of the ability to carry viruses
and bacteria in their systems and they are known to carry and transmit disease. Rodents have the
ability to carry many different pathogens that transmit disease including: plague, rat bite fever,
crytosporidiosis, hantavirus, Q fever, and much more. Different species of rats can hosts different
pathogens such as, the deer mouse being known to spread Hantavirus and the black rat is known for
the plague. Common signs you have rodent infestation are: hollowed snail shells under bushes &/
nesting sites, chewed citrus fruit near or on trees, greasy marks caused by the oils in fur along
corners &/ beams of buildings or fences, and by droppings left in frequently traveled areas.
MANAGEMENT
Good sanitation is effective toward rodent control but will not eliminate rats under every
condition, The presence of garbage, available food, and water helps rodents to thrive and
because rodents are “creatures of habit”, as long as what they need to survive is being met,
they will stay.There are several different means of rodent control the most efficient is rodent
proofing your home by making sure all openings ¼ inches or larger are sealed. This includes
openings where utilities conduits enter buildings, windows, screens, and doors. Bulk pet food
should be stored in containers with tight fitting lids. If rodent proofing does not eliminate the
problem there are other methods, which include trapping by either a baited snap trap or by
glue boards. Traps should be placed along walls where rodent activity seems highest.
Another method of control is rodenticides (poisoned bait) these can be purchased wherever
pesticides are sold. Do not purchase baits that look “homemade” or with incomplete labeling.
There are several advantages & disadvantages to either trap and is up for individual
digression. If the problem continues call a licensed professional to aid in rodent control.
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NORWAY RAT Rattus Norvegicus
One of the largest most common rat that goes by several different names:
Norway, brown, common, wharf, or sewer rat. This rat can be brown or
gray and approximately 25cm (10in) long with a tail that is shorter than its
body, weighing from 250g to 350g. This rat lives wherever humans live
especially in urban areas.
HOUSE MOUSE M. Musculus
House mice are approximately 7.5 to 10 cm (3.0 to 3.9 in) long not
including the tail, about 5 to 10 cm (2.0 to 3.9 in) long, and usually weighs
from 10 to 25 g (0.4 to 0.9 oz). They are typically light brown to black or
white to grey in color with very little hair on their tail and ears. House mice
have a vertical jump up to 45 cm (18 in). Their droppings have a strong
musty like smell, are blackish in color, and about 3mm (0.12 in) long.
These mice have the ability to survive in an array of conditions and are
found among homes, open fields, and commercial property. Like its rat
relatives the house mouse is also known to cause considerable damage
to property, contaminate food, and transmit disease causing pathogens &/or parasites
KANGAROO RAT
Kangaroo rats are small rodents that move bipedally (main transportation
is with two legs), can jump vertically 7 to 8 feet, and can rapidly change
direction minimizing predation and energy cost. Kangaroo rats have
massive heads compared to their body, large hindquarters and small front
extremities. They weigh approximately 128g (4.5 oz) , average about 8 to
14 cm (3.5 to 5.5 in) long and their tail can reach 16 cm (6.5 in) in length
ROOF RAT
R.rattus
More commonly known as the black rat it ranges from black to light brown
in color and is estimated to be 46.cm (18.25 in) long with a tail
approximately 17 to 25 cm (6.5 to 10 in) length, and weighs about 110g to
340g (4 to 12 oz). This rat is a tree dweller by nature due to its excellent
ability to climb. The black rat is typically prone to pine trees and palm
trees building large nest among the branches. When residing inside a
building they well typically build their nest in a hole/cavity above the
ceiling or beneath floorboards.
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RODENT CLEAN-UP
Rodents are reservoirs for various different
pathogens that cause disease. Some pathogens
can be transmitted through inhalation of
contaminated feces, urine, &/or salvia from
infected rodents. To safe guard against rodent to
human disease assume that all rodent bedding
and droppings are infected.
Completing clean-up by the following protocol
is necessary:
• DO NOT stir up dust by sweeping or
vacuuming up nesting materials,
droppings, or urine.
• Wear rubber, vinyl, or latex gloves
• Spray area in question with either a
disinfectant or mixture of 1 part bleach
to 10 parts water and let contaminated
area soak for 5 minutes. If using
disinfectant, follow the manufactures
instructions on the label for disinfectant
time and dilution.
• Use a paper towel to pick up disinfected
droppings, urine, &/or nesting and
immediately dispose of in the garbage
• When all rodent droppings and urine
have been removed, disinfect all
possible contaminated items.
Rodents http://www.cdc.gov/rodents/index.html
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