OTTENS G (2003) Background and development of the Dutch population of House Crows Corvus splendens. LIMOSA 76 (2): 69-74.

Originally native to the Indian subcontinent and adjacent areas, the House Crow has extended its range to parts of Southeast Asia, the Middle East and Eastern and Southern Africa. Most of these regions were colonised by ship. Recently, a small breeding population of House Crows was established at Hoek van Holland (near Rotterdam), along one of the world's busiest shipping routes. The Dutch birds probably originate from the nearest population at Suez, Egypt. Since the first breeding record in 1997, which was the first outside of (sub)tropical regions, numbers have been slowly increasing. Starting from two birds in 1994, the population at Hoek van Holland increased to 14 individuals in 2002. Individual House Crows were also observed at other coastal sites. These records involved both birds from Hoek van Holland as well as a number of new arrivals.
      In most countries where House Crows established a thriving breeding population, they are considered a pest species. In some colonised areas numbers of native birds have decreased considerably. Gregarious and aggressive by nature, House Crows are known to have replaced native corvids. Because of crop raiding, as noted in Africa, House Crows can also cause problems to humans. In some parts of eastern Africa and the Middle East the birds are even considered a health risk. Some fear that the establishment of a population in the Netherlands may facilitate a further spread in Europe. The author pleads for a decision to be made about terminating the Dutch population of House Crow.

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