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.
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)