There are two species of rat that might be encountered in Ireland. The Norwegian Rat (also known as the Brown Rat) and the Black Rat (sometimes called the Roof Rat). Rats are nocturnal, with their peak activity at dusk or before dawn. When the population is large or they are disturbed or hungry, you can also see activity during the day.

NORWAY RAT or BROWN RAT - (Rattus Norvegicus)

The Norwegian Rat is larger and more aggressive than the Black Rat. An adult Norwegian Rat can weigh between 12-16 oz. The coat is generally coloured dark gray on the back and off-white underneath, but may vary. The length of head and body is about 8-10 inches, with an additional nine inch tail, which is covered with rings of scales. Droppings are approximately 1/2 inch in length, capsule shaped, with blunt ends. They are usually a shiny black, but may vary according to their diets.

Adult Norwegian Rats live for about one year. Females average 4-7 litters a year, with 8-12 pups per litter. They live in colonies, and generally prefer to live in underground tunnels. Rats will seek food outside, but often come indoors at night to forage for food and return to their burrows. Needing a water source, they can obtain water from toilets, sinks, rain puddles, or condensation from utility pipes. Their nesting burrows on the outside are often along the foundation of walls. As the rat family grows, more burrows are built, resulting in a network of underground tunnels. Indoors, the Norway Rat commonly nests on the lower levels, but if the population is too large, they may be found in the attic and ceiling areas. Their nests are built from soft material like paper or grass chewed into small pieces. Rats will climb if necessary to enter a building, and the Norway Rat is an excellent swimmer.

ROOF RAT or BLACK RAT - (Rattus Rattus)

The Roof Rat (or Black Rat) is slightly smaller and more slender than the bigger Norway Rat. The adults weigh 5-9 ounces and the coat is generally black or gray-brown. The tail is hairless and covered with rings of scales. The snout is pointed, and the eyes and ears are large. The Roof Rat is a climber, commonly nesting in areas above the ground: trees, vines, attics, ceiling voids, or in voids along the roofline.

WEILS DISEASE or LEPTOSPIROSIS

Unfortunately, the Irish rat population is increasing, and between 50% and 60% of rats carry and excrete the organism Leptospira Ictero-Haemorrhagiae in their urine. Infection of humans with this organism causes an illness called Leptospirosis (which is also commonly known as Weils Disease).

Click here for further information on Leptospirosis or Weils Disease.

HOW TO TACKLE RATS

There are numerous methods one can use to control a rat infestation, depending on the type of rat and the location of nests and activity. As far as possible, eliminate harbourages such as gaps under sheds, loose piles of wood or neglected weed patches.

Poison rats with a proprietary, ready-mixed bait, easily available in most hardware stores or garden centres. Rat baits are available in block form or in handy sachets to be placed near signs of infestation. Rats are suspicious of changes in the environment or new foods, for this reason it may take a couple of days for traps or poison baits to take.

For serious or persistent rat infestations, contact X-Pest. We have at our disposal a range of rodenticide products which are not available to the householder, and the professional knowledge to deal with any infestation.

SOME USEFUL TIPS

Unscented baby powder or flour, lightly sprinkled can help you determine a rats tracks and their runways as they cross suspected areas.

If you think you might have a rat in your garden, take away any birdseed you may have immediately. You are probably feeding the rats unknown to you.

As all rats need water to survive, empty any water containers in the garden, and turn any empty flowerpots or containers upside down, so as they will not fill if it rains.

Ensure that there are no gaps around any pipes going through your exterior walls (tumble drier outlets, extractor fan outlets, etc.).

Secure the ends of any external piping with a fine wire mesh to stop any rodents entering through the pipes. But take care not to block waste water from flowing out.

If you are using snap traps, use a piece of cooked rasher rind as the bait, but tie it on to the trap. Place your traps unset the first day. This will help the rat to get used to the new obstacle in its routine path. Also, try placing two traps side by side, so that if the rat manages to avoid the first one it might get caught in the second one!

If you come across any droppings in the house, keep a sample to show to the pest control technician. This makes identification of your infestation much easier. (But always wear gloves!)