3 months ago
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Parliament is spending more than £100,000 a year on pest control in a bid to keep at bay the 'super-mice' plaguing the corridors of power.
Hundreds of mice have been spotted in the Palace of Westminster in the last year alone, and the Commons now employs a full-time pest controller to combat the problem.
The super-mice evade traps and are immune to poisonous bait - and they are thought to have demonstrated the 'first-ever' case of resistance to the anticoagulant rodenticide, difethialone.
Over the past three years, both Houses of Parliament have spent a combined total of almost £360,000 on pest control - equivalent to more than £119,000 a year.
The Commons pest controller uses 'humane and ethical' methods focused on prevention.
Over the past three years, both Houses of Parliament have spent a combined total of almost £360,000 on pest control (stock image)
But the House also uses 'control methods' including baiting, breakback trapping and even hawk flying.
Authorities blame Parliament's proximity to the River Thames and Westminster Underground station for making the estate particularly vulnerable to pests.
The latest 'Rodent Control Strategy' says there has been behavioural resistance on the estate for around 20 years, making it 'difficult to find baits that the mice will eat'.
But the use of anticoagulant poisons is also 'severely restricted by the high levels of resistance in the mouse population at the Palace of Westminster'.
House authorities have previously asked the University of Reading to carry out DNA tests on mouse tails which indicated a 'very high incidence of resistance, not only to first generation anticoagulants, but also to difenacoum and bromadiolone'.
It adds: 'We also suspect that we now have resistance to difethialone (if this is the case it is the first-ever case of resistance to difethialone in house mice) and have ceased using formulations containing this active ingredient.
'Unfortunately, because no previous cases have ever been identified we are not able to prove the difethialone resistance.
'However, Reading University are searching the DNA profiling data for additional unexpected mutations.'
Last year, the Commons was given a low food hygiene rating after mouse droppings were found in 19 different places.
Last year, the Commons was given a low food hygiene rating after mouse droppings were found in 19 different places (stock image)
A Parliament spokesman said: 'Parliament is a safe place to work, with robust hygiene processes in place.
'We are committed to maintaining a humane and ethical pest control programme, focused on preventative measures and, where necessary, the use of various control methods.
'Value for money remains a key consideration and we will, as ever, continue to follow all legislative and regulatory obligations.'
Staff in the Palace of Westminster have long had to contend with mice in their offices, forcing some workers to take matters into their own hands by sourcing traps.
In 2014, Penny Mordaunt - now the Commons Leader - brought her own cat to Parliament to tackle the issue.
She shared photos of her cat in her Commons office on Twitter, captioned: 'Great believer in credible deterrence, I'm applying the principle to the lower ministerial corridor mouse problem.'
