Kids Go Free
Louth Museum

Ruth's Blog

National Rat Week

by Ruth Gatenby

Brown rat

Brown rat

1919 letter

1919 letter

During and after World War I, there was a shortage of food in Britain.  It was critical that food was not wasted, for example by being eaten or spoilt by vermin.

The letter shown here was written in December 1919.  It was sent from the Lindsey Agricultural Executive Committee to all Parish Councils, announcing two more National Rat Weeks between 29 December and 1 March.  It states that all persons occupying premises infested with rats were responsible for clearing them of the pest, and were liable to prosecution if they neglected to do this.  It says that the Rats Organising Officer could give information and assistance as to the methods to be employed, and help secure supplies of poison at a reasonable rate.

Black rats had first arrived in Britain in the 1st century and brown rats, which are now the predominant species, came in the 18th century.  Rats eat growing crops and stored food, they contaminate food with urine and faeces, and they can transmit diseases to people.  Rats live in groups, usually in sewers or cellars.  A female can produce up to five litters a year, so a group can grow from 2 rats to 15,000 in a year.  If most of a group is exterminated, the numbers quickly build up again.

The Rats and Mice (Destruction) Act 1919 aimed to control vermin.  At that time, rat catchers already had a long-established understanding of rat behaviour.  Their knowledge was reproduced and formalised.  Methods of control included denying rats access to food, and catching and killing them with traps and dogs.  Early rat poisons were arsenic and strychnine, but these are highly toxic to people and have no antidote.  Warfarin became available in the 1950s, and there are now several types of rat poison. 

Today control of rats follows the same principles.  Store foods in sealed containers or out of reach of rodents, and when using poisons take great care to put them in tamper-resistant containers not accessible to children and non-target animals, and to dispose of dead rats carefully to prevent secondary poisoning.