Global invasive potential of the house crow Corvus splendens based on ecological niche modelling

Abstract

Summaries of recent rapid range expansions shown by the house crow Corvus splendens have provided insights into the global nature of this invasion process, but its long‐term potential has not yet been evaluated. To explore the potential dimensions of this geographic expansion, we used ecological niche modeling based on known occurrences of the species on its native distributional area, in the context of GIS data sets describing climatic variables, topographic information, and human presence. Our models provided predictions of areas already invaded that were statistically significantly more coincident than expected under random (null) models. The predicted potential range of the species includes areas already affected, as well as potentially suitable areas in Central America, the Caribbean, equatorial and West Africa, and mainland and insular Southeast Asia, not yet colonized.

The House Crow (Corvus splendens): A Threat to New Zealand?

“…This use of ecological niche modeling technique is similar to other studies for predicting the potential geographic distribution of a range of plant and animal invasive species such as mammals [50], birds [9,51], plants [52,53], amphibians and reptiles [54,55], insects [56] and fish [57]. Invasive bird species have been shown to have a higher success of establishment and spread in novel areas if the climate match is similar to that of the native range [58][59][60][61].…”

“…ENM and SDM are being used in a wide variety of domains such as threatened species mapping [43][44][45][46], disease vector mapping such as mosquitoes carrying dengue and malaria [47] and invasive species potential distribution [48,49]. ENM has already been used by Nyári et al [9] to predict the global potential invasive range of the house crow. In this paper, the term ENM is used to cover the intent of both definitions.…”

“…In the Hoek van Holland a breeding colony is known to have survived winter temperatures as low as −8 °C [9].…”

“…Often mis-identified as other crow species, the sexes are phenotypically similar, although the males may be slightly larger in size, and they have a characteristic smoky-grey collar [7]. It is an adaptable, gregarious, noisy, commensal bird, which only lives in close association with humans in urban/semi-urban areas and is not known to live independently from humans [8,9]. They are also known to be associated with coastal human inhabited areas [8] and, although foraging independently and in small groups during the day, they do exhibit communal roosting at night [10,11].…”

“…[13,23,24], Newcastle disease [25,26] and the potential for spread of bird flu [27]. This bird is globally regarded as an important pest species with significant potential for further global invasion [9,13,21]. Using a risk analysis model, the Vertebrate Pest Committee (VPC) [18] in Australia has classified the house crow as an extreme threat species while the risk of establishment has been determined as a serious risk in Australia [28].…”