Partridge Count Scheme

JOIN THE PCS The country’s wild grey partridges need more land managers, especially those with only a few grey partridges, to join the Partridge Count Scheme. Find out more at www.gwct.org.uk/pcs.

National over-winter survival only dropped from 55% to 53% despite the cold weather in spring 2018. © Dave Kjaer

KEY FINDINGS National over-winter survival for 2017/18 was 53%. Productivity, recorded as Youngto-Old ratio, increased by an average 13% to 2.6 young birds per adult. Average autumn density across all PCS sites increased 8% to 21 birds per 100ha.

Neville Kingdon Julie Ewald

In spring 2018, Partridge Count Scheme (PCS) members submitted 470 spring counts, down from 527 the previous year. A total of 5,532 pairs of grey partridges were counted on 144,710 hectares (ha), down 274 pairs (-5%) on spring 2017 when a total of 171,350ha was counted. The grey partridge stronghold in eastern England continues to report nearly two-thirds of all the pairs recorded in the PCS, yet comprises only one third of participating sites. Nationally, spring pair density decreased by 10% to 3.8 birds/100 ha, although pair densities in southern England and the Midlands remained static. Pairs in eastern England and Scotland increased by around 5%, achieving averages of 2.2 to 5.1 pairs/100ha. Northern England recorded the largest decline (-29%) in pair density.

The national average over-winter survival (OWS) rate for 2017/18 was 53%, a small drop from the 55% of 2016/17. As a ‘Barometer of the Countryside’ this is good news for grey partridges regarding losses during the winter period. Many PCS members made particular comment about the cold and snowy weather at the beginning of spring 2018, and about the subsequent rain. Although PCS members in eastern England recorded the largest decline (-13%) in OWS to 53%, as compared with their 61% OWS in 2016/17, their OWS was at a high starting point compared with most other regions of the UK.

Summer 2018 stands out as one of the warmest and driest summers of the past 100+ years, with little appreciable rainfall for most areas (parts of southern England recorded less than 5% of the June average rainfall), until August when average temper

Figure 1

40

Spring grey partridge pairs per 100 hectares (95% CL)

0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 Trends in the indices of grey partridge density, controlling for variation in the different count areas 35 30 25 20 15 10 5 New sites Long-term sites ACKNOWLEDGEMENTS We are extremely grateful to GCUSA for its ongoing support of our grey partridge work.

TABLE 1

Grey partridge counts

Densities of grey partridge pairs in spring and autumn 2017 and 2018, from contributors to our Partridge Count Scheme

Number of sites Spring pair density Number of sites Young-to-old ratio Autumn density (spring) (pairs per 100ha) (autumn) (autumn) (birds per 100ha)

Region

2017

2018 2017

2018 Change (%)

2017

2018 2017

2018 2017

2018 Change (%)

South 61 63 1.9 1.9 0 79 81 2.3 2.0 12.1 9.8 -19 East 141 141 4.8 5.1 6 133 143 2.3 2.7 21.7 22.3 3 Midlands 100 85 2.9 2.9 0 91 91 2.3 2.3 18.0 19.4 8 Wales 3 2 2.3 0 -100 3 2 1.8 - 4.4 0 -100* North 134 109 6.8 4.8 -29 134 111 2.4 3.0 26.8 36.7 37 Scotland 87 69 2.1 2.2 5 73 69 2.3 2.5 11.1 11.3 2 N Ireland 1 1 9.9 7.9 -20 1 1 0.3 1.0 5.3 13.3 151*

Overall 527 470 4.2 3.8 -10 514 498 2.3 2.6 19.3 20.8 8

* Small sample size. The number of sites includes all those that returned information, including zero counts. The young-to-old ratio is calculated from estates where at least one adult grey partridge was counted. The autumn density was calculated from estates that reported the area counted.

atures returned. While wildfires and flash floods made the news, it was brood-rearing habitats and sufficient chick-food insects for hatching broods that were of more concern to partridge managers.

The PCS received 498 autumn counts in 2018 (see Table 1). The total number (old and young) of grey partridges recorded nationally was 24,600. The total area counted covered 154,510ha. This was 5% less than the 161,750ha counted in autumn 2017 and the average area counted by PCS members remained stable at 321ha (down from 324ha in 2017).

Autumn density for the UK was 20.8 birds per 100ha, up 8% from 19.3 per 100ha in autumn 2017, but there was a wide variation between regions with the highest densities recorded in northern England (34.6 birds per 100ha) and, other than Wales, the lowest being southern England (10 birds per 100ha).

The Young-to-Old ratio (YtO), an easy measure for comparing breeding success, recorded a national increase of 13% from 2.3 to 2.6 young birds to every adult and remained well above the 1.6 threshold level necessary to cover adult losses into next year. The southern regions noted a decline in YtO (-13%).

Weather has certainly dominated the partridge counts of 2018. Both partridges and counters faced challenging conditions in the first few months of the year, only to be followed by a summer we have all wanted in a good while. But the many weeks of heat resulted in an advanced harvest. This was well underway by the time autumn counts began and, for PCS participants, it had an impact on access for counting to varying degrees. Regardless, overall 2018 has been a positive year for grey partridges and if winter survival for 2018/19 is as obliging then we hope to have good news to report in the spring counts.

BACKGROUND Partridge counts can offer valuable insight into how well your partridges breed, survive and benefit from your habitat and management provision throughout the year. Each count (spring and autumn) is easy to carry out and helps assess the previous six months without the need for continual monitoring. How to count:

Record what partridges you see – using binoculars helps when examining each pair or covey.

Spring: Ensure winter coveys have broken up and breeding pairs have formed – typically in February and March. Record all pairs and any single birds.

Autumn: Wait until most of the harvest has finished – ideally between mid-August and mid-September. Record adult males, adult females and young birds in each covey separately. Don’t assume a covey is two adults and some young.

Use a high 4WD to drive around fields and then criss-cross the whole field to check the entire area, using the tramlines to minimise crop damage. www.gwct.org.uk/pcs.