The kea population has declined 50-80% over the last 3 generations, or 36 years, largely due to persecution, and continues to decline rapidly.
Although kea populations appeared stable in 2001, especially in national parks and other protected areas, their population trend is currently decreasing and continuing to decline rapidly.
The population is a fraction of what it once was, largely due to persecution between the late 1860s and early 1970s, although pockets of high population densities persist in some areas, such as around Arthur’s Pass and South Westland.
Recent survey data indicate that kea have undergone substantial recent population declines.
For example, density in the upland beech forest of Nelson Lakes National Park in 2011 was approximately one adult female Kea per 2,750 hectares, down from about one per 550 hectares in 1998. This represents an 80% decline in density over 13 years or just over one generation. There are also numerous anecdotal reports of decreases from other unmanaged areas. Although densities in other populations are much higher than at Nelson Lakes, it is likely that kea in areas not subject to predator control are continuing to decline. The total population decline over the last three generations, or 36 years, is likely to have been more than 50% but less than 80%.
Further research is being conducted on the kea’s ecology, genetics, and population dynamics. The population needs to be censused at frequent intervals. The feasibility of a captive or island insurance population needs to be investigated.
• Image | © Makalu, Some Rights Reserved, Pixabay
• Sources | (BirdLife International, 2017; del Hoyo, Elliott, Sargatal, Christie, & de Juana, 2017; Diamond & Bond, 1999; Orr-Walker, Kemp, Adams, & Roberts, 2015; Williams, 2001)