Chick Food Index

Key findings

  • Long-term studies show that chick-food insects remain few in number in UK wheat crops.

Our insect monitoring programmes continued in Sussex and at Loddington, Royston and on two estates in France. We use the insect data to calculate the Chick Food Index (CFI) from which we can predict partridge chick survival and likely population change between years. To maintain populations, a CFI of 0.8 is needed. It is clear that in England supplies of insects for chicks are still woefully inadequate in commercially-farmed winter wheat (see Figure 1) and the same is true of many other arable crops. Insect numbers can, however, be sufficiently high in set-aside and other non-crop habitats.

However, we are still unsure how such habitats should be arranged across each farm and whether set-aside can be improved to enhance biodiversity. To this end we are being funded by the Sustainable Arable LINK programme, along with our partners The Arable Group, Rothamsted Research and the British Trust for Ornithology, to answer these questions over the next four years.

The Chick Food Index in commercially farmed winter wheat in five study sites, 2002-2005

Further reading

  • Moreby, S.J., Aebischer, N.J., & Southway, S.E. 2006. Food preferences of grey partridge chicks, Perdix perdix, in relation to size, colour and movement of insect prey. Animal Behaviour, 71: 871-878.
  • Ewald, J.A. & Aebischer, N.J. 1999. Pesticide Use, Avian Food Resources and Bird Densities in Sussex. JNCC Report No. 296, Joint Nature Conservation Committee, Peterborough.
  • Aebischer, N.J. 1991. Twenty years of monitoring invertebrates and weeds in cereal fields in Sussex. In: Firbank, L.G., Carter, N., Darbyshire, J.F. & Potts, G.R. (eds) The Ecology of Temperate Cereal Fields: 305-331. Blackwell Scientific Publications, Oxford.

Get your FREE Grey Partridge Conservation Guide

An essential guide to conserving the grey partridge produced by the Game & Wildlife Conservation Trust.

What's inside your FREE guideGreypartpages

✓ The decline of a common farmland bird
✓ A safe place to nest - plenty of tussocky grass
✓ Chick survival - insect food is crucial
✓ Surviving winter and spring - food and cover
✓ Conservation targets - Partridge Count Scheme
✓ Grey partridges and shooting
✓ Common questions


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