Pest control (4)

Carrion flies

These will mainly be bluebottles and greenbottles, Calliphora and Lucilia spp which are known to most people and are easily recognised by their metallic blue or green colouring. They are large and hardy flies, the eggs of which are usually laid on carrion, into which the larvae burrow and feed for around a week to 12 days, depending on environmental conditions. Pupation takes place in soil or, if indoors, in cool dry locations.

The larvae are also very hardy, and will survive long periods at around five degrees centigrade, and will survive shorter periods of freezing.

Flies of both genera are strong fliers, and are attracted to pretty much any dead animals.

Farmers Weekly, suggests an average mortality rate of between 8.1% and 11.2% in free-range systems, and applying the mid - point of this range, 9.65%, to the proposed flock at Cononsyth suggests that over a year some 6176 birds will have died. Many of these will of course be found by workers on site, but it is doubtful if they all will, especially as they have a range area of approximately 80 acres to patrol.

Taking into account the above notes on flies, it is very likely that surrounding dwellings up to a mile or more from the sheds are likely to suffer significant problems with flies, particularly during the summer months, and especially so when the sheds are de–populated. In addition to proximity to the sheds themselves, several dwellings are right alongside the propose range area, and are much more likely to have fly problems.

If the proposal does get the go-ahead, then we would hope that the applicant would compelled to financially support the installation of fly screens and other insect control systems at properties affected by flies.

REFERENCES

1. https://extension.umn.edu/preserving-and-preparing/handling-eggs-prevent-salmonella

2. "Salmonella outbreak linked to British eggs". https://www.foodsafetynews.com/2020/07/salmonella-outbreak-linked-to-british-eggs/

3. https://www.hse.gov.uk/agriculture/zoonoses-data-sheets/leptospirosis.pdf

4. "Filth fly (diptera) oviposition and larval development in poultry manure of various moisture levels." S. Fatchurochim; et al Journal of Entomological Science (1989) 24 (2): 224–231.

5. "How far can House flies fly?". L. Townsend. https://entomology.ca.uky.edu/ef506#:~:text=There

6. https://www.fwi.co.uk/livestock/poultry/free-range-can-be-better-if-issues-are-addressed