A hole in a wall the size of a 25 cents coin is all that is needed for a rat to squeeze through, while the gap only needs to be a size of a dime for a mouse.

Small holes left by cables and wires under the eaves or through walls are all that is required for a rodent to gain entry and start rummaging for scraps of food or gnawing into electrical wires.

The extent of Bermuda?s rodent population is unknown, but even at a conservative estimate it is thought many thousands live on the Island.

It is enough of a problem for each member of the Department of Health?s Pest Control team to dedicate two days of their working week to tracking down the vermin and advising property owners how to reduce the chance of a rodent infestation.

Because rats are primarily nocturnal they are not often seen or reported. And people who do see a single rat often do not bother to call up Vector Control because they think ?Oh, it?s only one rat.? But as Russ Furbert, general foreman of the pest control team, points out if there is one rat you can guarantee there are many more in the vicinity. The quicker the source of food that is sustaining them can be located and eradicated ? the better. During the longer evenings of summer there tends to be more reports because people are out and about as the rats begin to emerge from their hiding places. And at Christmas time the rats also appear more active with more food and scraps being discarded by households.

Bermuda is home to two types of rat one is the common roof rat, which does a lot of high-wire walking along power lines, utility poles and trees to reach food sources.

The other is the Norway rat, which burrows underground much of the time when not out hunting for food.

?When there is heavy rainfall the burrows become flooded and the Norway rats come out in numbers,? said Mr. Furbert.

In both cases the rats are on a mission to find easily accessible food ? and man?s increasingly throwaway lifestyle provides an ideal hunting ground, as was evident when Mr. Furbert and vector inspector Kevin Place took out to see some likely rodent ?hot spots?.

First stop was a set of communal trash dumpsters under an open air covering. The metal dumpsters had no lids ? making it easy for rats to hop inside and nibble through the plastic trash bags. Nearby some discarded pieces of carpet and foam were a ready source of bedding and nest-making material for the rodents.

Mr. Place spotted ?weeping holes? in nearby brickwork, an ideal egress point for the underground-dwelling Norway rats to reach the trash.

?I believe all new condominiums should have enclosed areas for their dumpsters, with stone surrounds,? said Mr. Furbert. Inspecting the weeping holes in the retaining wall, he added: ?We can tell if they are around by dirt and grease marks around the holes from their bodies.?

On the opposite side of the road is another likely hiding place for the rats ? undergrowth and foliage. Spotting a rodent during the day is rare, but when there is a shortage of food or an increase in the rodent population they can be forced out into the daylight. ?At times when there is a heavy infestation they come out during the day because there is not enough food at night. The weaker rats will be forced to come out in the day to find something to eat,? explained Mr. Furbert. Bermuda?s rats do not carry diseases, but it would only take one disease-infected rodent to reach the Island for that to change, and the rodents do posses a health risk through their droppings and urine. Mr. Furbert has clear advice for residents who want to avoid attracting rodents to their property. The number one tip is to ensure there is no ready food source available.

?Put garbage out on the day it is being collected ? not the night before. If it is put out on the day it is picked up it will be gone by that afternoon and rodents will not have got to it because of all the daytime activity,? he said.

People can also freeze scarps of food before they put them out to reduce the scent, or use a toxic spray or substance to make the scraps inedible. Putting trash in a bin with a lid, and one preferably of metal construction, because rodents can gnaw through the bottom of plastic containers, is another good deterrent according to Mr. Furbert.

Visiting a second location he and Mr. Place find discarded wood and fittings providing an ideal hiding place for rats. The property owners have laid a plastic rat trap box. There is no dead rat visible, but the rodenticide supply in the trap is running low ? evidence rodents have been around. The Department of Health?s Vector Control section sell the plastic rat trap boxes for $15 and will come out to check them and service them with fresh poison. The dumping of rubbish along roadside verges on secluded lanes creates another feeding ground for rodents. Less than 400 metres from the Tynes Bay waste treatment centre there is prime example. Amongst the rubbish is a broken TV, an old refrigerator and plastic bags of rubbish that had been been gnawed through by rodents.

Another location that warrants attention is a plot of land that has been cleared to make way for a new development. Demolishing a property can unleash an infestation of rodents around a neighbourhood if the creatures have been living in the old building. That is why Mr. Furbert would like to see a closer working relationship with the planning department so that his team receive notification of construction and demolition projects and can lay bait traps were necessary to deal with any rodents before they are disturbed.

He would also like to see the introduction of ticket penalty fines for people who disregard warnings from his officers about having properties that are harbouring or attracting vermin. The current law allows for court fines that start at $336 and can increase on a daily basis of $84 if no action is taken to address a rodent problem. But the court system can be cumbersome and the department prefers to work out problems with a householder.

A typical vector inspector?s day would entail picking up report sheets with tracking numbers and going out to visit residents and properties, assessing the impact of the rodent problem and placing traps where necessary as well as advising householders how to clean up the area to lessen its attractiveness to rodents.

Bait traps are normally checked for a number of consecutive weeks until the bait is no longer being taken.

Data gathered from rat sightings and investigations is put into an interactive central computer system that allows the pest control section to identify hot spots, trends and even predict the likely movement of rat groups to new feeding grounds. Using the reports and the tracking numbers of assignments helps collate this information.

But the bottom line remains awareness by residents about what they can do to eliminate food sources for the rodents.

Using proper bins and putting trash out on the day of collection is a good start. Composting areas in gardens should be protected and maintained and fruit falling from trees should be collected rather than being left on the ground.

Pet owners should be careful not to leave excess food outdoors that will attract a rat, nor should bird seed that has fallen from a feeding table be allowed to remain on the surrounding ground.

On March 18 it is Earth Community Clean-Up Day. Mr. Furbert and his department are locating areas on the Island that are in need of attention so that the details can be passed on to the clean-up day?s lead body Keep Bermuda Beautiful.

He also hopes that residents might rally around to clean up their neighbourhood, or individuals simply have a tidy-up of their own property on that day.