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During a census in gardens in Hamilton, 71.8% of the 4428 birds observed belonged to introduced species. A total of 15 species were observed. Bird species richness was positively correlated with native plant biomass and, more strongly, with total plant biomass. More birds were present in gardens with more native plants. Among the most common species, the abundance of the House Sparrow (Passer domesticus) decreased with increasing percentage of native plants, the Silvereye (Zosterops lateralis) increased, while Blackbirds (Turdus merula) and Starlings (Sturnus vulgaris) showed no significant change. This was typical for a other introduced bird species. Most other birds, including the Fantail (Rhipidura fuliginosa) and the Grey Warbler (Gerygone igata), were most abundant in gardens with higher native plant biomass. Notable was the absence of the Tui (Prosthemadera novaeseelandiae) from all censused areas in Hamilton at the time of observation. No significant variation between morning and evening samples was noted.