BG Grey Partridge 14th Feb

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					                          Grey Partridge
                                                             Perdix perdix

  Biodiversity Briefing
                                                                                               Population dynamics
The Grey Partridge Story
                                                                                               Breeding habits
                                            Where to see it
                                                                                               In late winter after the break up of
                                                                                               their winter covey (family group) grey
                                            In lowland arable areas of Great Brit-
                                                                                               partridges form pairs. They are mo-
                                            ain from the chalk areas in the south,
                                                                                               nogamous and in spring hens seek
                                            into East Anglia, Lincolnshire and
                                                                                               out suitable cover for nesting. The
                                            Nottinghamshire, reaching into the
                                                                                               nest made on the ground is usually
                                            north of England and the east of
                                                                                               scrape lined with grasses. Eggs are
                                            Scotland as far as Aberdeenshire.
                                                                                               laid a few weeks later. Incubation,
                                            There are small populations in other
                                                                                               which lasts 23-25 days, can begin as
                                            parts such as the permanent rushy
                                                                                               early as the end of April, although
                                            pastures in the north Pennines. They
                                                                                               mid-May is more usual. Hens lay be-
                                            are largely extinct as a wild species
                                                                                               tween 10 and 20 eggs at 1-2 day in-
                                            in N. Ireland.
                                                                                               tervals (no other wild British bird lays
                                                                                               more eggs than the grey partridge).
The grey partridge is a medium-sized                                                           The choice of a good nest site is vital
gamebird with a distinctive orange                                                             if the hen is to survive this critical pe-
face. This is the native species to Brit-                                                      riod of 38-55 days when she is on her
ain and is not to be confused with the                                                         nest and vulnerable to predation.
French or red-legged partridge. It likes
cereal and pasture fields with thick                                                           Brood rearing
hedges and wide field margins
nearby.      During winter, partridge                                                          Once hatched, chicks leave the nest
move into uncultivated areas and                                                               within hours, following their parents in
stubble fields. They fly with whirring                                                         search of food. At this stage the par-
wings in short bursts and occasional                                                           ents lead their chicks into brood-
glides, showing a chestnut tail. They                                                          rearing covers such as cereal fields to
eat leaves, seeds and insects. It’s                                                            protect them from predators. Insects
call is a harsh ‘skeeer-ick’ sound.                                                            are a vital part of the chick’s diet in
                                                                                               the first two to three weeks of life.
                                                             Yellow - Optimum habitat          Without this source of protein, they
                                                             Green - Less optimal habitat      can starve to death. They are also
                                                             Grey - Unsuited
                                                                                               susceptible to cold wet weather and
                                            Grey partridge habitat in Britain (from CEH Land   can quickly die if poorly fed.
                                            Cover and OS Geographic Reference maps)

Why do they matter?
The decline in numbers of grey partridges in the UK, and across Europe is well documented. Populations declined by 86%
from 1967 to 2000, though in some mixed farming areas, especially in the north, numbers appear to have stabilised. But in
some areas with historically low numbers, for example, intensive grasslands in the west, declines have exceeded 95%.
The magnitude of the decline has led to grey partridge being identified as one of the most threatened farmland species in
the UK Biodiversity Action Plan (BAP). The Government’s targets for grey partridge, set out in the plan, are:
• To halt the decline by 2005 (this target is being reviewed in 2006)
• Ensure the population is above 150,000 pairs by 2010
• Enhance the current geographical range of this species, where biologically feasible.

  Produced by the CPA on behalf of the Voluntary Initiative in association with Game Conservancy Trust,
  the lead partner for the UK Government’s grey partridge biodiversity action plan                   
     Key factors for decline                                                                                       What
•    Loss of nest sites (such as hedge bottoms) and grassy field margins.               Provided there are some grey par-
•    Loss of winter stubble feeding grounds for over-wintering birds.                   tridges on the farm or close by,
•    Reduced food supplies and sources for chick food through the use of pes-           then it is possible to increase their
     ticides and herbicides.                                                            numbers by addressing three key
•    Vulnerability of nests to predators on farmland with poor cover.                   factors:
•    Nest destruction caused by early mowing and other farm operations.
                                                                                        1. Nesting cover
                                                                                        2. Chick food (insects)
                                                                                        3. Predator control eg corvids
Why can't we solve the                         Partridges and pesticides                   and mink
problem by releasing birds?
                                               The Game Conservancy Trust have          All three are vital and each one
                                               shown that grey partridge chicks de-     needs to be satisfactorily ad-
                                               pend on an adequate food supply of       dressed if numbers are to be en-
                                               invertebrates, many of these in turn     couraged. Without any one of
                                               depend on weeds. Consequently in-        them, the population will not re-
                                               secticide and herbicide use may indi-    cover.
                                               rectly affect chick survival by remov-
                                               ing food sources. There is a relation-   However, small changes can
                                               ship between insecticide applications    make a big difference. The ability
                                               and lower breeding success.       May    of this species to recover quickly
                                               and June insecticide applications can    is huge. You only need a few
                                               eliminate invertebrate food supplies     more successful coveys or a few
                                               for farmland birds. Early spring and     more chicks per covey to increase
                                               autumn insecticide applications are      your partridge densities greatly.
                                               less destructive allowing some recov-
For two reasons. First, the partridge has
declined primarily because farmland has
become inhospitable through agricul-
tural intensification, restoring the habitat
should always be the priority. Second,
hand-reared partridges do not behave
naturally in the wild and are vulnerable
to predators. Low populations are unsta-
ble as they can disperse and become
vulnerable. Even those that do survive
usually fail to breed successfully in sub-
sequent years.

Populations can recover
Case study
Located south-west of Royston, the project demonstrates how to restore numbers
of wild grey partridge. A 76% increase in the spring grey partridge numbers has
been achieved using the following measures:                                             You should also consider:
1.     Predator control to improve the survival and breeding success.                   1. Providing winter cover for food
2.     Habitat improvement, relying on best use of set-aside and, where possible,          and shelter
       contracting into existing agri-environment management options such as            2. Offering additional winter and
       those offered under the historic Countryside Stewardship scheme. The area           spring food
       is still farmed well.                                                            3. Follow good shooting practice
3.     Year-round supplementary feeding.
4.     Maintaining pheasant numbers at 2001 levels, thereby providing some
       shooting for local farmers.

can be done?
  1. Spring nesting cover
  Hens nest on the ground in thick grassy cover. Crucial elements of a successful nest site are large amounts of resid-
  ual dead grass and the nest site height above general field level. Dead grass provides the nesting material and the
  bank prevents nest sites becoming waterlogged.

  Do’s and don’ts
      Construct beetle banks* across large arable fields to increase the amount of nesting cover. If the field slopes, site
      the beetle banks* along the contour as this will help to protect any nearby water from field run-off.
      Manage the grass beside hedgerows so that there is always old dead grass from the previous year available for
      Keep hedge height trimmed (after berry crop has finished) below six foot to avoid them being used as look-out
      posts by avian predators.
      Make judicious use of set-aside strips to create grassy nesting cover beside cereal crops.

      Don't plough to the hedge line. You must not plough within 2m of the centre of the hedge (Cross Compliance)
      Don't allow fertilisers or herbicides to drift onto hedge or fence banks - they will damage vegetation used as
      nesting cover.
      Never spray fence-rows with herbicides. Rough grasses at the base of fence-rows are the only nesting habitats
      left in many areas.
      Don't allow livestock - especially sheep - to
  graze out and damage the base of hedges
  when adjacent fields are in grass. Some light
  grazing every few years may be beneficial.

  * Grant aid is available for these under some
  Agri-environment Schemes. See ELS handbook
  option: EF7

  2. Summer insect food
  As well as insects, brood-rearing cover needs to
  be within a tall canopy of vegetation to conceal
  young chicks from predation but open enough
  at the base to allow small chicks to move
  through it. It must not be too dense, nor retain water which can quickly chill and kill chicks after heavy rain.

  Do’s and don’ts
      Use conservation headlands* along cereal crop edges. The key features are:-
      •     Non-selective herbicides and summer insecticides are not applied on cereal crops along a 6 to 24 metre strip
            at the field margin.
      •     Fungicides can be applied as normal.
      •     Some selective herbicides and grass weed-killers can be applied to combat cleavers, black-grass and other
            problem weeds – seek current advice.
      •     On heavy land, nitrogen levels are best reduced (see ELS options).
      Plant set-aside strips with cereal mixtures (wild bird cover option*) next to nesting cover.
      Use set-aside allocations to their maximum effect around the farm, combine nesting cover (sown grass) with brood-
      rearing cover (cereal mix) within the same strips.
      Leave some bare soil between the hedge bank and crops. It prevents weeds infesting crops and provides a drying-
      out/dusting area for partridge broods.
      Don't apply summer insecticides to cereals unless there is no other choice. The deleterious effects of a large-scale
      application can last for several years. If treatment is necessary, use a selective insecticide or leave the outer 12
      metres unsprayed.

  * Grant aid is available under some Agri-environment Schemes. See ELS handbook option: EF 9-10

 Copyright Crop Protection Association             
   What can be done? cont’d

   3. Winter cover for food and shelter
   Tall vegetation needs to provide cover from predators, shelter and food (seeds, leafy material etc) through-
   out winter.

   Do’s and don’ts
        Sow seed-bearing game crops* such as kale or quinoa in open areas where partridges are likely to
        be and not close to woodland.
        Leave stubbles as long as possible before cultivation. Stubbles following an undersown crop are par-
        ticularly valuable because they remain uncultivated giving access to spilt grains and weeds seeds.
        Use the wild bird cover option* of set-aside with a kale-quinoa mixture left for two years. In winter and
        spring this provides food and protection from predators.
        Consider spraying stubbles with selective herbicides that will knock out problem weeds while leaving
        the others as partridge food.
        Avoid planting new woodland in open areas suitable for grey partridge.

   * Grant aid is available for these under some Agri-environment Schemes. See ELS handbook option EF2, EF3 or EG2

   The grey partridge and shooting
   The grey partridge is no longer the prolific gamebird it once was and, in
   areas where it is uncommon birds should not be shot. Partridges are most
   abundant in the places where they are managed and conserved for shoot-
   ing. Some properties, in good breeding years, produce a surplus. In these
   circumstances and, provided not more than 30% of the autumn population
   is shot, the shooting can be sustainable.

   Note: Grey partridge should only be shot if you are taking steps to
   manage them and if you have more than 20 birds per 100 hectares.

   Care should be taken when redleg shooting to ensure that grey partridge
   are not shot.

   Monitoring grey partridge numbers
   The Game Conservancy Trust (GCT) is the lead partner for the UK Gov-
   ernment’s Grey Partridge Biodiversity Action Plan. As part of this role, the
   GCT guides farmers through the basics of management and carries out
   regular counts to monitor the success of habitat improvement.
   Interested farmers, landowners, land managers, keepers and individuals
   who have agreed access to land can count partridges twice a year and
   submit their counts (including zeroes) to the national database.

   In summary, to increase grey partridge numbers we need to Further sources of information:
                                                                                    Game Conservancy Trust:
         Provide more habitat areas (ELS or HLS options may pay for this).
        Use pesticides on the “as much as necessary, as little as
                                                                                    The British Trust for Ornithology:
        possible” basis.
        Follow the principles of integrated farm management and make
                                                                                    The Royal Society for the Protection of
        the most of non-cropped areas
        Avoid late season and broad spectrum insecticides.
                                                                                    Crop Protection Association:

Copyright Crop Protection Association
Pictures: Grey partridge cover photo - Alexis de la Serre. Covey photo - The
Game Conservancy Trust/Francis Buner. Other photos/images - The Game
Conservancy Trust and Crop Protection Association
January 2006

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