Up until the publication of ‘The Birds of Morocco’ (Thévenot et al. 2003), the House Bunting (Emberiza sahari) was only recorded as a vagrant in Tangier. By mid-2000s, it started to breed in the Medina of Tangier (Birding World 19: 263). How the original nucleus population started to breed in Tangier, however, is still a matter of opinion, i.e. captive origin vs. natural arrivals from the south.
The origin of the very first birds in the vicinity of the barber’s shop in the Medina of Tangier does not really matter now that the House Bunting is well established in the city. Moreover, this population is increasing and continually expanding to many new districts. Apart from the known nucleus population at the Medina described in the note cited above, the House Bunting was found very abundant in the “Casabarata district” with many singing males and juveniles in May 2009 (Sander Bot & M. Amezian). It was also found abundant in “Brans district” (R. El Khamlichi & M. Amezian) in October 2011 (see video below). The species most likely occurs also in many other places such as the Kasbah and Marshan (all these districts are distant from each others).
In other parts of Morocco, the species breeds mainly in holes and crevices in buildings, but only occasionally in trees. In Tangier, Cortes (2010) recorded the breeding of a House Bunting in a trunk of a Canary Island date palm in spring 2010.
On the other hand, I knew from Spanish colleagues that there was some debate about the nature of House Bunting occurrence in Spain, i.e. natural vagrancy vs. human-assistance (e.g. by ships or escapes). For instance, the first ever House Bunting for Spain was considered probably an escaped captive bird (de Juana 1994). For now, I can only say that here in the southern shore of the Strait of Gibraltar, the House Bunting is doing very well (as summarised above), so probably more of them will cross the Strait in the near future. So, be prepared to see more of them!
Amezian, M, Bensusan, K., Perez, C. & Thompson, I. 2006. Is House Bunting about to colonise Europe? Birding World 19: 263.
Cortes, J. 2010. A House Bunting Emberiza sahari nesting in a palm tree in Tangier, Morocco. Gibraltar Bird Report 9: 44-45.
de Juana, A., E. & el Comité Ibérico de Rarezas de la SEO. 1994. Observaciones homologadas de aves raras en España y Portugal. Informe de 1992. Ardeola 42: 103-117.
Thévenot, M., Vernon, R. & Bergier, P. 2003. The Birds of Morocco. BOU Checklist No. 20. BOU, Tring.