Bird species richness and abundance: The effects of structural attributes, habitat complexity and tree diameter

Structurally complex habitats influence species richness and abundance through the provision of resources and microhabitats. This study examines the effects of structural attributes, habitat complexity (expressed as habitat complexity score) and tree diameter (expressed as standard deviation of diameter at breast height), on bird species richness and abundance. Projected foliage cover and diameter at breast height of the five closest trees and bird richness and abundance were recorded at the 30 survey sites within the Kioloa Coastal Campus. Regression analyses were conducted between the structural attributes and bird richness and abundance. A statistically significant correlation (α=0.05) was found between habitat complexity score and bird richness and abundance. A similar relationship was observed with the standard deviation of diameter at breast height. Land managers can employ these findings to enhance habitat restoration and rehabilitation projects, and to monitor biodiversity outcomes.