The use of cellular telecommunication towers as nesting sites by pied crows (Corvus albus) in an urban mosaic landscape

Abstract

Corvids are known for their urban exploitation, often using artificial infrastructure to roost and nest. In many areas of its distribution range, the pied crow (Corvus albus) is often common in areas of anthropogenic land use, often breeding and foraging near human settlements. In this study, we monitored pied crow use of cellular telecommunication towers as nesting sites in Pietermaritzburg, South Africa, during three breeding seasons. We found that of the 36 towers situated across the urban mosaic landscape, pied crows used 17 (47.2%) as nesting sites while 19 were not used. Many towers were used in subsequent years as nesting sites. Overall, 41 pied crow nests on towers in urban mosaic landscapes were counted by the end of the study. Towers had a mean (± SE) distance of 1595.2 ± 151.0 m between them and were located mainly in the suburbs of Edendale and Northdale. As shown by the hotspot analysis and spatial distribution of used and unused towers, it was unclear why some towers were not being used as nesting sites. We assessed the relationship between pied crow nesting sites and land cover features. We found that tower nesting was best explained by cropland (wi = 0.58), forest (wi = 0.94), grassland (wi = 0.66), schools (wi = 0.56) and relief (wi = 0.56). The continued persistence of pied crows in urban mosaic landscapes with natural and /or managed green spaces, the availability of anthropogenic infrastructure and food in these, and their behavioural plasticity will likely increase their numbers in such landscapes.