| UPLANDS - GREY PARTRIDGES
Winter feeding grey partridges on the fringe We want to encourage more people to feed partridges on hill farms to provide emergency food sources to help survival in severe winters. © Phil Warren/GWCT
BACKGROUND In the UK, grey partridge numbers have declined by 93% between 1970 and 2018 and the species has been red-listed as a Bird of Conservation Concern since 1990. Declines have chiefly followed intensification of cereal production. Grey partridges are also found on hill farms in northern England, but numbers here are susceptible to high mortality during severe winters and poor breeding in wet summers.
26 | GAME & WILDLIFE REVIEW 2020
Grey partridges in the UK are mainly associated with lowland cereal farms, but they are also found on marginal hill farms in northern England where they frequent rough grasslands created by low-intensity sheep farming. Here, availability of winter food, particularly in years with prolonged snow, appears a major limiting factor, with birds lost from formerly occupied habitats following the severe winter in 2009/10. Winter feeding is a widely adopted component of wild partridge management in lowland cereal systems. However, in the uplands, although winter feeding occurs, it is largely targeted at pheasants and feeders are often in woodlands, which are generally avoided by partridges. To investigate whether food shortages in winter limited partridge survival, we experimentally increased the provision of supplementary food over two winters. We hypothesized that feeding would improve over-winter survival and breeding productivity. We selected 10 study plots in Upper Teesdale, County Durham, which were paired in relation to their size and altitude. Plots were on average 2.1km². A low level of winter feeding was already present, with partridges using 17 feed hoppers provided by the local wild pheasant shoot. These were all mapped and we then randomly assigned the increased feeding treatment to one of the paired plots and a network of feed hoppers were installed. We aimed to provide two hoppers for each known autumn covey present, with 57 hoppers provided in the first winter (2010/11), increasing to 76 in the next (2011/12). Owing to the presence of grazing livestock, all hoppers were fenced to exclude sheep and cattle. Feeding was undertaken between November and May, with hoppers checked weekly and filled where necessary. At each visit, partridge use was assessed through recording sightings of birds and searches for their droppings around the hopper. We surveyed partridges across all study plots at dawn or dusk in spring (March, repeated in April) and again in summer (August, repeated in September) using a callplayback method. The surveyor played an audio recording of a calling male from a vehicle at 10 vantage points along a four-kilometre route along minor roads and tracks through each study plot. At each stop, the observer listened for calls of responding birds and mapped all encounters. Grey partridges were attracted to feed hoppers, with birds using them a median of 31 days (range 2-104 days) after hoppers were installed, with 96% of hoppers used in the first year, and all were used in the subsequent year. We found no differences in over-winter survival between feeding treatments or years, which averaged 62% (see
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