The species of rodents includes mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. They are mammals that are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws.
We will be focussing on the brown rat, the black rat and the house mouse, as these are considered serious pests, eating and contaminating food, damaging property and spreading diseases. In 2003, the amount of rice lost to mice and rats in Asia was estimated to be enough to feed 200 million people.
The black rat is infamous for spreading a wide range of bacterial diseases that cause fatal illnesses such as the bubonic plague, typhus, Weil’s disease, Lyme disease, toxoplasmosis and trichinosis.
While the largest species can weigh up to 65kg, most rodents weigh less than 150g. They use their sharp incisors to gnaw food, excavate burrows and defend themselves. Most eat plant material, but many will eat pet food and meat scraps around the home as well. They multiply quickly and will easily overrun a dwelling and attract other pests as they find and store food scraps.
Rodents generally have well-developed senses of smell, hearing and vision. Nocturnal species often have enlarged eyes and some are sensitive to ultraviolet light. Many species have long, sensitive whiskers or vibrissae for touch or “whisking”.
Rodents can seriously damage the structure of your home. They will gnaw through the insulation and walls. They have been known to chew on electrical cables causing shortages in the circuit and electrical fires. Their burrowing can leave structures such as walls with no support as they hollow out the soil underneath. Rats can also be aggressive when threatened, posing a major risk to pets and small children.
It is important to note that while rodents can cause destruction, disease and injury in urban communities, they also play an important role in our ecology. Burrowing rodents may eat the fruiting bodies of fungi and assist seed dispersal. As such, these rodents may play a role in maintaining healthy forests.
Some rodents are considered keystone species and ecosystem engineers in their respective habitats. In the Great Plains of North America, the burrowing activities of prairie dogs play important roles in soil aeration and nutrient redistribution, raising the organic content of the soil and increasing the absorption of water.
There are various noticeable signs that will clearly indicate that rodents have taken up residence in your home:
- Rat Droppings – dark brown in colour and resembling the size and shape of rice grains. Rats can produce a cluster of about 50 droppings per night.
- Footprints – in dusty areas, tiny footprints will be clearly visible. These footprints will also assist in locating the main nesting area.
- Nests – will be located in warm, dark areas and contain any ‘nesting’ material such as newspaper, cardboard or fabric.
- Scratching Noises – you may hear them scurrying under decking, sheds and floorboards. They are more likely to be identified by a grinding noise they make with their teeth known as bruxing. Larger rats will run along the roof or scuffle along the ceiling beams.
- Trails – their oily, dirty fur will leave smudges and dark marks on both objects and surfaces they repeatedly brush against.
- Burrows – look for burrows in compost heaps, under decking or garden sheds.
- Damage – they will gnaw on any wood and plastic in your home. They have the potential to cause fires by chewing through electrical cables. You may also notice ripped food packaging, as rats tear open food, leaving visible teeth marks.
If you suspect that you do have rodents, contact a professional pest control company. Traps and poison are inhumane and can be fatal to pets and children. A professional company has been correctly trained to effectively remove them safely from your home.