The Independent (Britain's best newspaper) had an article today (March 26th) on the rat problem in Flamborough, Yorkshire. Here's a quote from the article.
The main cause, argues the National Pest Technicians Association (NPTA), is the decision of local authorities to start charging up to £100 a time to deal with rat problems within their borders. Fortnightly bin collections and the decomposing mountains of discarded takeaway food that litter our streets are also to blame. But the well-intentioned householder must also shoulder some responsibility. Inadequately covered compost bins, the allotment boom and over-stocked bird feeders are fuelling the problem. In Flamborough, it's the weather that's to blame. Waterlogged and snow-covered fields over winter meant local farmers were unable to plough in the rotting stubble, unwittingly providing an unlimited food source for this ever-opportunistic and resourceful rodent.
One householder also blamed the practice of shooting hawks, which I didn't know was a problem in Britain. On our farm, we have a plethora of sky-born predators and they are constantly patrolling the fields. We also have cats who bring in a big fat vole every so often, as well as the occasional unwary robin.
The problem of rubble and the use of cover crops that provide cover and food for rodents is an aspect that postmodern farmers might want to consider futher. I do some fall tilling as it disturbs the slug eggs and allows me to get into the fields a few days earlier in the spring. This is a tradeoff as there is a question of erosion, even with my flat ground. There is also the question of disturbing the biotic community underground. I am not totally committed to fall tilling, however. I am pointing this out as an example of the multiple variables inherent in every farming decision. Growing up on a farm in Minnesota, it was more of a time question than an erosion question. If you are still picking corn in November, there is no time to plow. Nowadays, I do some fall tilling and some fall cover crops. I also left some grain in the field last year and this attracted a lot of birds, including a brace of pheasants, which now worry me because of their scratching in the dirt.