Decline and potential recovery of the European grey partridge (Perdix perdix) population—a review

Abstract

Grey partridge populations showed drastic decreasing numbers throughout Europe. Existing knowledge of the causes of decline and the effectiveness of conservation measures was reviewed. Population studies from the UK indicated three periods: a stable population before 1950, sharply decreasing numbers in 1950-1970 and a continued decline after 1970. Other European studies fitted into this picture, with a 10-year lag in each period. The onset of population decrease corresponded with a sharp decrease in chick survival mainly caused by reduced insect availability due to pesticide use. Several factors caused the continued decreasing numbers after 1970, such as decreased hatching success and an increased role of predation. Measures to restore partridge numbers should firstly focus on the main cause of population decline, that is, improve foraging conditions to increase chick survival rate. Next to creation of special partridge habitat, conventional agriculture offers good opportunities to improve foraging conditions. Only when an integrative approach is adopted may large-scale habitat improvements be realised to restore population level to the level before 1950.

Landscape structure, predation of red foxes on grey partridges, and their spatial relations

“…One of the reasons for the drastic decline in the grey partridge populations throughout Europe during the last few decades was the decrease of nesting success, which was attributed to increased predator numbers and negative changes in agricultural landscape structure [10,25,31]. This study supported the previous prediction that habitat changes and predation may interact to cause population declines of farmland birds [32].…”

Autumn–winter diet of Grey PartridgesPerdix perdixin winter crops, stubble fields and fallows

“…In this context, the reduced tillage systems, that are used by an increasing number of farmers in western Europe and which rely on the use of herbicides to control weeds that emerge from the post-harvest stubble (Cunningham et al 2004), are less beneficial to Grey Partridges and several other species of seed-eating bird, in comparison to the traditional maintance of stubble fields. Crop fields which are uncultivated for a longer period of time (2-3 years), overgrown by biennials and perennials due to vegetation succession, have a considerably smaller value for Grey Partridges (reviewed by Kuijper et al 2009). …”

“…However, creating areas of both weed-rich land-cover types, i.e. stubble fields and cover crops with natural regeneration of annual weeds (as discussed above) alongside areas of winter cereal crops, will provide the best landscape for a recovery programme of Grey Partridges in arable regions of Europe (Kuijper et al 2009.…”

Integrated Farming Methods and Their Impact on Biodiversity of the Landscape

“…In connection with accepting the standards of the European Union's Common Agricultural Policy, there has been a steady slight increase in the use of chemical substances for the protection of plants (Václavík, 2006). Marked differences in the abundance of individual species can be seen when comparing the abundance and occurrence of individual species in the states of eastern and western Europe (Donald, et al, 2001), as well as in island versus continental settings (Kuijper, et al, 2009), which differ in their farming styles. However, Hole et al (2005) draw attention to the fact that a number of studies comparing conventional and organic farming comes from Western Europe.…”