The localized environmental degradation of protected areas adjacent to bird feeding stations: a case study of the Australian brush-turkey Alectura lathami

摘要

This study investigated the potential for wildlife feeding to artificially increase population densities of the Australian brash-turkey, Alectura lathami and assessed the indirect adverse effects that this may have on surrounding forest floor vegetation. Census counts and observations of feeding activity conducted in recreation areas of Australia's Gold Coast hinterland confirmed that brash-turkey population densities were significantly elevated by the provision of food by humans. Brush-turkey densities were high at sites where birds are actively fed, moderate at sites where birds feed opportunistically and low at sites where humans have negligible impact on local food availability. Brush-turkeys caused significant environmental impact at sites where their population densities have been substantially elevated by active feeding. Across all sites, increases in brush-turkey density were accompanied by a significant decline in ground cover, leaf litter weight, seed density and seedling density. Natural environmental variables such as gradient, vegetation type and canopy cover did not explain the observed impacts. The impacts were consistent with those described in trampling studies and suggest that at high density, even small animals can have significant trampling impacts on their local environment. This study demonstrates that wildlife feeding can have detrimental impacts on the integrity of local environments and recommends greater consideration of small animals and their potential indirect impacts when regulating wildlife feeding in National Parks and other nature conservation areas.