On 12 October 2016 Christine and I drove to a complex of reservoirs to the west of Antequera. In my experience these reservoirs in Spain normally attract few birds apart from gulls and the occasional Cormorant. On this occasion, however, one of the reservoirs, Embalse de Guadalhorce, held flocks of Coot and Pochards that are normally more abundant on the shallower lagoons in the region. However, after a prolonged drought these shallow lagoons were completely dry. On this occasion, among a group of Cormorants resting on a promontory were two Egyptian Geese. I had come across these geese (more closely related to Shelducks than true geese) on two previous occasions in Andalucía: on 5 October 2004 I found a pair on a temporary roadside pond to the north of Antequera, just south of the turn to the MA201 off the N331, and on 22 January 2013 I saw a pair, again on a temporary roadside pond, where the A6213 leaves the A45 motorway just south of Antequera.
Egyptian Geese are widely and commonly distributed across sub-Saharan Africa, where they are mainly resident but some undertake northerly migrations into the normally arid Sahel, sometimes recorded as far north as Algeria and Tunisia during the wet season. In West Africa they breed as far north as southern Mauritania but the closest approach of their breeding range to Europe is in the Nile Valley in Egypt. Here, they were formerly more widespread (and domesticated) and appear in hieroglyphs, suggesting that they were regarded as sacred in ancient Egyptian society. They also bred in Israel until the 1930s and they even nested as far north as the Danube basin in eastern Europe until the early 18th century. There are uncertainties about their former occurrence as breeding birds in Africa north of the Sahara but occasional occurrences in the northern winter in the Red Sea coasts of Arabia, Cyprus, Malta, Algeria and Tunisia are thought to be vagrants from tropical Africa.
Interpretation of origins of Spanish records is complicated by the establishment of feral populations, derived largely from waterfowl collections, in parts of Europe, notably in Britain, the Netherlands, France and Germany. Eduardo de Juana and Ernest Garcia (Birds of the Iberian Peninsula, 2015) report that Egyptian Geese have now been seen in most parts of Spain but especially in the east (Catalonia) and south (Extremedura and Andalucía), mostly in winter but with occasional records of breeding. They found no evidence of birds originating in Africa, noting that there were no accepted records from Morocco. In 2002 a pair of Egyptian Geese that bred in Majorca was, along with their five chicks, killed on the assumption that these were not wild birds from Africa (Atlas de las Aves Reproductoras de España, 2003). However, Egyptian geese do occasionally occur in winter north of the Sahara in Algeria and Tunisia (www.avibirds.com) and there has been a recent report of an Egyptian Goose being seen at Ifrane National Park in Morocco (https://www.africanbirdclub.org/node/2095?language=pt-pt).
Nevertheless, there remains doubt about the origins of these birds. Those seen in southern Spain could be from African stock, but equally those seen in Africa north of the Sahara might have originated from feral populations in Europe. We should not rush to conclusions about the origin of Mediterranean records of Egyptian Geese until genetic or chemical studies have been undertaken to discover whether birds of European and African origins can be differentiated.
This problem is not restricted to Egyptian Geese. On 16 March 2008 I found three Ruddy Shelducks in a large flooded pool near Campillos and Ernest Garcia and Andy Paterson (Where to watch birds in southern and western Spain, 2008) reported that while they used to be recorded more often, they still appear regularly in winter on southern coastal areas and probably originate from birds that breed in Morocco. Eduardo de Juana and Juan Varela (Aves de España, 2005) thought that some sightings in Spain might refer to birds that had escaped from captivity, or that some might even stem from populations that breed in eastern Europe.