Further Records and Updates of Range Expansion in House Crow Corvus Splendens
Colin Ryall 39 Bull. B.O.C. 2016 136(1) Further records and updates of range expansion in House Crow Corvus splendens by Colin Ryall Received 31 May 2015 Summary.—House Crow Corvus splendens continues its ship-assisted global invasion, reaching locations further from its native range in the Indian Subcontinent. This report reviews the species’ recent spread as well as changes in the status of existing introduced populations where information is available. With the collapse of long-standing eradication programmes in Kenya and Tanzania, and a spread to inland sites in both countries, it is inevitable that House Crows will colonise the heart of Africa. In South and East Asia too, the species is spreading unobstructed through the region. Nevertheless, there is now a growing recognition of the threats of invasive alien species in general, including House Crow, and a willingness by some authorities and funding bodies to prevent the species’ proliferation. As a result, control programmes are now in operation at several locations where House Crows have established, and increasingly proactive approaches involving risk assessments, surveillance and action plans are being developed where a risk of invasion exists. Native to the Indian Subcontinent, southern Iran, Myanmar and western Yunnan (China), House Crow Corvus splendens has, over the past century or so, shown itself to be an invasive alien species (IAS) that is progressively spreading globally. Initially, the spread was mediated by deliberate releases in Aden (Yemen), Zanzibar and Klang (Malaysia) as of the late 1800s, for the purpose of dealing with refuse and crop pests. However, this was soon superseded by ship-assisted range expansion, at first within the Red Sea, Indian Ocean and its islands, probably via ships from Mumbai and Colombo, but also from ports including Aden and Suez, which possess large House Crow populations.
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