Houseflies: Regulations And Unintended Consequences
  Key Words  
  Poultry, waste, refuse, compost, recycling, Musca, Fannia.
  Clive Boase
  In the United Kingdom (UK), legislation is sometimes used to prevent pest problems or to facilitate pest management. However in recent years, the two pieces of legislation that have had the most significant impact on common housefly, Musca domestica, infestations across the UK, were not intended to address fly problems at all. Formerly, most household waste in the UK was tipped in landfill sites. However in order to reduce the loss of potentially useful recyclable materials, a Landfill Tax was introduced in 1996, which placed a charge on all waste going to landfill. Alternative processes and products such as In-Vessel Composting, Mechanical and Biological Treatment, and Refuse Derived Fuel were developed, and were very successful in reducing the volume of waste going to landfill. However several of these new process have been found to be vulnerable to housefly infestations. There have been numbers of cases of fly nuisance to neighbouring properties, and the pest management and waste industries have been working hard to identify solutions. Separately, most poultry eggs were formerly produced by hens kept in small battery cages in deep pit units. These units were vulnerable to infestation, and often generated housefly populations that caused problems for neighbours. The European Welfare of Laying Hens Directive came into force in January 2012, and was intended to improve caged birdsí welfare by requiring hens to be kept in larger cages. The design of the manure removal system associated with these new cages resulted in common housefly populations almost disappearing from caged layer units, a cessation of fly nuisance cases, and a dramatic drop in insecticide usage. The unintended impacts of these two regulations have had a dramatic impact on UK fly populations, both positive and negative. These two examples emphasise the importance of proper scrutiny of new legislation by pest management professionals, in order to avoid unintended consequences. They also illustrate the possibility of creating pest management legislation that works in conjunction with industry on a national scale, to remove conditions conducive to urban pests.