Rats

Rats – An Overview of the Rat

History

The brown rat, common rat, sewer rat, Hanover rat, Norway rat, Brown Norway rat, Norwegian rat, or wharf rat is one of the best known and most common rats. The domestic or fancy rat is descended from the Brown Rat (also known as the Norwegian Rat) and is thought to have originated from Asia moving into Europe in the 1500s. It lives in burrows and is a good swimmer and can often be found inhabiting sewers.

There can be much prejudice against the rat due to the spread of plague, but it was the Black Rat that played a part in this epidemic and it was not the rat itself that carried the plague but the fleas that it carried.

In the early 1800s rats were kept, and bred and used for ratting contests where rats were released and terriers were competed as “rat catchers”. In the late 1800s rats were bred in captivity for scientific research into nutrition, intelligence and disease and it was noted in the laboratories that the rat was highly suited as a pet due to its intelligence and tameness. By the late 1800s rats were kept in captivity as pets and by the early 1900s had become a popular pet. However, the keeping of rats as pets declined in later years due to the introduction of more “appealing” pets such as the hamster but the popularity of the rat as a pet is once again rising.

Rat Biology

• The brown rat is usually active at night and is a good swimmer
• Brown rats dig well, and often excavate extensive burrow systems.
• Brown rats have been found to posses a mental ability previously only found in humans and some primates.
• The fur is coarse and usually brown or dark gray, while the under parts are lighter gray or brown.
• The length can be up to 25 cm (10 in), with the tail a further 25 cm (10 in), the same length as the body.
• Adult body weight averages 350 g (12 oz) in males and about 250 g (9 oz) in females, but a very large individual can reach 500 g (18 oz).
• Brown rats have acute hearing, are sensitive to ultrasound, and possess a very highly developed olfactory sense
• The brown rat can breed throughout the year if conditions are suitable, a female producing up to five litters a year. The gestation period is only 21 days and litters can number up to fourteen, although seven is common.
• The maximum life span is up to three years, although most barely manage one.

Where Do Rats Hide?

• Burrows outdoors underneath decks, porches and sheds
• Warm areas like attics
• Soft warm areas such as insulation
• Forested and ravine areas/properties

Common Rat Misconceptions

Misconception 1
Where do rats live? I thought they only infested dirty places.

Reality
Not true…even the cleanest of homes can have an infestation. Common rats live in any situation that provides food, water and shelter thus making the kitchen a perfect place to stumble upon a rat. The common rat is the most widespread of its species and is widely found in urban and rural areas. In homes they will live in loft spaces, wall cavities, cellars or under floorboards. In gardens, they will burrow into compost heaps and grassy banks or under sheds. They are also commonly found living in sewer systems.

Misconception 2
I’m not scared of rats, so it’s not a big deal if there is one or two in my home.

Reality
Despite the fact that many people like rats as pets, an undomesticated rat is more likely to transmit diseases to humans, eat or contaminate food intended for humans, cause damage to buildings and other structures by gnawing and burrowing, chew wiring rendering the damaged wire a fire hazard amongst other things.

Frequently Asked Questions

Q: How can I tell rats and mice apart?
A: Adult mice are much smaller than adult rats. Adult mice weigh about 30 grams, and fancy mice tip the scales at about 50 grams. Adult mice have bodies that are 3-4 inches long with 3-4 inch tails. Adult rats are far heavier and longer: they can weigh ten times as much, averaging 350-450 grams for females and 450-650 for males (with an overall range of 200-800 grams). They have 9-11 inch long bodies and 7-9 inch tails.

Q: Some people get really freaked out about disease from rats? Should I be concerned?
A: Similar to other rodents, rats may carry a number of pathogens which can result in disease, including Hantavirus Pulmonary, Murine Typhus: Murine typhus, Rat-bite fever (RBF), Salmonella, Leptospirosis, Eosinophilic Meningitis. Rats can also serve as a reservoir for Toxoplasma gondii, the parasite that causes toxoplasmosis, though the disease usually spreads from rats to humans when domestic cats feed on infected brown rats.

Q: What are possible solutions for my rat infestation?
A: There are a number of ways to treat your rat infestation. With an inspection by your pest professional, we can determine the most frequented and nesting areas and commence a baiting and trapping program.

Q: Why isn’t the bait I have working for me?
A: Pest professionals have access to high quality bait available to licensed technicians and have the experience and knowledge of baiting and trapping behind them to best pinpoint areas of infestation and nesting. They are also equipped to sometimes determine the path of travel helping to place bait stations in areas where they will be most effective.