Farmers need to strengthen their defences as rats prepare to make their annual migration from ditches and hedgerows to cosier accommodation among the farm buildings. Peter Hill reports.
Oh for a latter-day Pied Piper to lead those pesky critters away. Unfortunately, only more prosaic means of keeping rat populations at acceptable levels are available to farmers.
Poison baits are the most commonly used measure but their use is coming under ever increasing scrutiny over their potential effect on non-target species.
The Health and Safety Executive has proposed a stewardship scheme that would require anyone setting poison baits to undergo appropriate training.
This is already available to farmers wanting to optimise control techniques, as well as to professional pest controllers who recognise the merit of understanding how best to use them responsibly with the least possible threat to wildlife.
Top 10 tips for controlling rats
- Minimise the attractiveness of the farm environment. “This is usually overlooked but so important,” says Adrian Meyer of FarmTrain, which provides certificated rat control training in association with Lantra and pig industry body Bpex. “Tidy up the farmyard and remove any shrubbery, long grass, old machinery and general debris, ideally within a 30m radius of farm buildings,” he advises.
- As a second line of defence against the agility of these creatures, close all holes and possible points of entry – such as where pipes pass through a wall – and eliminate openings around doors and windows. Guards on downpipes and screens on grilles and airways will also help.
- Remove debris that rodents can use for nesting, such as piles of wood, piping, rubble and old equipment. It can also help to minimise availability of water near farm buildings, such as ponds, ditches and stagnant pools.
- Feed stores need to be secure, well maintained and kept as rat-proof as possible. If telltale droppings are found, action is needed. “Livestock farmers face a specific set of issues, most evidently the fact it’s difficult to remove the rodent’s source of food,” says Mr Meyer.
- Get trained. FarmTrain’s one-day Bpex course covers these issues in addition to disease threats, poison resistance, alternatives to baiting and safer baiting approaches in line with standards promoted by the rodenticide industry’s Campaign for Responsible Rodenticide Use (CRRU). “The purpose of the CRRU code is to ensure that effective rodent control can be carried out by all users, while ensuring that the exposure of all non-target animals, including wildlife, is kept to an absolute minimum,” says campaign head Alan Buckle.
- Dr Buckle advocates a planned approach to baiting control programmes, which should have a start, middle and end. “It may take as few as 14 days and usually no more than five weeks to clear a rat colony, depending on the severity of infestation,” he says.
- Sharon Hughes of BASF Pest Control Solutions is dubious about the effectiveness of proprietary bait stations given the natural wariness of rats, and advocates creating bait stations from materials already found in their environment. “Rats have finely honed survival instincts based on a huge wariness of new things,” she explains. “It makes them reluctant to enter confined, unfamiliar spaces and even more reluctant to feed in them. Besides, they prefer to eat sitting on their haunches so they can be alert to any threats around them.”
- Cold, shiny plastic boxes with at least one right-angle turn and mostly too small to sit up in or to eat in a group won’t attract rats. Instead, Ms Hughes suggests using familiar, readily available farmyard materials such as corrugated iron, wooden sheeting, pallets, slates, tiles, bricks, blocks or old tyres to build simple bait stations puts rats at greater ease, and with a bit of thought can be made as secure as most tamper-resistant boxes to non-target species.
- “Robust construction and small enough entry points to deny dog access are important,” Ms Hughes adds. “Sturdy wooden trays around 150 x 76mm (6 x 3in) make good bait containers, protected by an immovable structure with an entry height of about 76mm (3in) and an internal height of 150-200mm (6-8in).”
- Wooden or corrugated-iron sheets propped up at a shallow angle against walls and weighted down with bricks also work well, Ms Hughes says. As do pallets raised up on bricks, blocks or old fence posts and securely covered with sheeting; the same goes for loose stacks of bricks or blocks roofed with old tiles or slates.
An online register of CRRU Wildlife Aware-accredited pest control technicians is maintained on the Basis website under “exams and training”
The online Farmers Academy provides a course and test worth two Basis CPD and one Farmers Academy Fads point.