Galliformes 6: Grey Partridge

Grey Partridge

Before the increase in managed shooting estates aimed at pheasants, the most commonly hunted gamebird in Britain was the Grey Partridge, Perdix perdix. One of three species in its genus, the natural range extends from the Arctic Circle south to the Mediterranean, and from western Europe across to western China. To the east and south of its range it is replaced by the very similar Daurian Partridge, P. daurica, and on the Tibetan plateau by the rather distinct Tibetan Partridge, P.hodgsoniae.

Daurian Partridges

Grey Partridges are classic birds of agriculture. When humans invented agriculture they quickly shifted from their original grassland habitat to cereal crops, where they feed on weed seeds and grain chiefly. For the first few weeks of their lives however the chicks are dependent on insects, especially plant bugs and sawfly larvae, and this has been the cause of a major decline in the UK as agricultural development greatly reduced this crucial food source. Records from shooting estates show that between 1870 and 1930 the annual bag of grey partridges was around 2 million birds annually, and a breeding population at the start of the season of around 1 million pairs. The estimate in 2000 was for a wild population of around 70,000 pairs, and the number is probably much less today. Similar declines have occurred in the rest of western Europe, from similar causes.

Tibetan Partridge

Efforts to change this have had limited success. Leaving undeveloped headlands in fields provides cover and a food resource for chicks, and on game estates artificial food supplies, especially in the crucial spring period when natural food sources are at their lowest after the winter can also help, but in the wider farmed landscape Grey Partridges are increasingly a rare sight.

Grey Partridges are quite prolific birds, laying up to 20 eggs in a clutch, so they can rebuild numbers quite quickly if they have a properly managed habitat. This year however the weather has resulted in a catastrophically bad breeding season. It has been estimated that to maintain numbers the birds need a chick survival to adulthood rate of around 1 in 3 chicks – this years wet weather has given a survival of around 1 in 7. If 2013 is a good year they may replenish their numbers, but for the winter shooting season the GWCT is recommending that Grey Partridges should not be hunted, rather the more common (and introduced) Red-Legged Partridge, which I will write about next week.

Although artificial rearing and releasing of Grey Partridges is perfectly possible, survival especially after a ‘hard release’ is often low, and farmed birds can have an adverse impact on the survival of wild populations. Research is ongoing on how to best increase the numbers of Grey Partridge, but although key findings on chick survival and habitat are now known, translating them into action on the ground is proving much harder.

Wild Grey Partridges spend the non-breeding season in family groups called coveys, splitting up into individual pairs at the start of the breeding season. The nest is a scrape in the ground lined with dry grass, often situated on a south facing slope at the edge of a field. Hedges with more than 10 trees per kilometre are avoided, as these provide too many vantage points for sharp eyed nest predators like crows and magpies. The incubation period is around 23 days and the chicks leave the nest within a few hours of hatching.

Outside their natural range, Grey Partridges have also been introduced to North America, likewise for hunting purposes, and can be found along most of the cereal producing regions along the USA/Canadian border. In the US it is often called the Hungarian Partridge or ‘Hun’. Whether these have had an impact on native gamebirds is unclear.

Further reading:
GWCT website on Grey Partridge management at http://www.gwct.org.uk/research__surveys/species_research/birds/grey_partridge_bap_species/default.asp


(image from wikipedia)