Red-legs take up residence

Much to the delight of some of my office colleagues at the British Trust for Ornithology, a pair of red-legged partridges has taken up residence in the meadow outside our window. Despite my initial indifference to these introduced birds, I have to admit an increasing, if somewhat grudging, feeling of tenderness towards them. The two birds are full of character and behave like an old married couple, confident in each other’s company and without the need to indulge in any overtly showy behaviour.

The species has a fairly long, if somewhat patchy, history within Britain, having been first introduced by Charles II in 1673. This attempt, involving the liberation of a number of individuals at Windsor failed, as have so many other attempts since that time. However, an introduction near Orford (Suffolk) by the Marquis of Hertford in 1770 was successful, perhaps because he introduced the birds as eggs, brooded here under chickens but of French stock, and the population has increased and spread since then. It has always struck me as a bit odd that people should go to so much trouble in order to introduce a species that is widely regarded as being a poor sporting bird. Red-legs (or Frenchies as they are sometimes known) show a propensity to escape on foot when flushed for the guns.

Part of the difficulty in establishing the species here comes down to our climate. Red-legged partridges are birds of hot dry areas within their small native range (which takes in France and Spain, together with a small part of Portugal and Italy). As such they only seem to prosper on light, free-draining soils within areas of low rainfall. This may go some way to explaining why they seem to do well here in the Brecks. The wider distribution within Britain shows a close match to those areas where the average maximum July temperature remains above 19 degrees. Within suitable habitat, however, the red-leg is capable of great reproductive output, the female laying two separate clutches of eggs, one straight after the other, which are then incubated simultaneously – the female on one clutch and her mate on the other. The resulting chicks soon learn to feed on grass and weed seeds, with a small proportion of insects, something that makes them less vulnerable to the effects of pesticides than the native grey partridge. The numbers of red-legs probably peaked many decades ago, since when there has been something of a decline, initially linked to the poor-breeding success associated with hybridisation (with the introduced chukar) but now down to a decline in habitat quality. Our population of these birds is now the third largest of any country in the world, so perhaps I should hold them in greater esteem.