Friday, 5 October 2012

Galliformes 7: Red-Legged Partridge

A.rufa (France)
In 1770 a new species of partridge in addition to our native Grey Partridge was introduced into the UK for hunting. This was the Red-Legged or French Partridge, Alectoris rufa, and releases continue to this day on game estates.

There are around seven species of Alectoris partridge alive today, which together occupy a range extending from Western Europe across to China, and from the Mediterranean south into India. They are absent from sub-Saharan Africa, and as a group they prefer sandy habitats with much less plant cover than the Perdix partridges, which probably explains why they were not native to the UK.
A.philbyi (Yemen)
Red-Legged partridges are rather easier to raise in captivity than Perdix partridges, as the chicks are less dependent on insects, instead feeding more on small seeds and plant parts. As a result, the eggs could be raised under bantam hens (these days electronic incubators are used) and the young birds raised to independence quickly before being released on hunting estates. They are also extremely prolific, with hens producing two clutches of up to 20 eggs a year. The usual habit is for one clutch to be incubated by the male and the second by the female, allowing large numbers of young to be produced practically simultaneously. This is probably part of the groups adaptation to dry habitats – when rain falls and the desert blooms there is a brief window of good food resources, and this breeding habit enables them to take full advantage.

Unfortunately for the British population, it was discovered that hybrids of Red-Legged and Chukar partridges were even more prolific in captivity, and many were released, thus polluting the gen pool of the wild breeding birds, whose productivity declined. Releasing of hybrids has now ceased, and the productivity has recovered, aided by the large numbers of pure Red-Legged that are now released instead. This makes the British population of some importance globally, as the native Red-Legged in its natural range of France and Spain is declining as a result of agricultural changes, although the IUCN still lists it as Least Concern.

A.chukar (Asia)
Today, the main distribution in the UK is centred on Norfolk and Suffolk, the driest parts of the UK and with a farmland landscape that suits the species. Even so, the agricultural changes that have caused its decline in its native range are also at work here, and the wild population has fallen considerably. The current estimate for wild Red-Legged in the UK is between 90,000 and 250,000 pairs at the start of the breeding season.

Next week – grouse

(images from wikipedia)

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