Kea (Nestor notabilis) are highly inquisitive parrots endemic to Aotearoa/New Zealand that often interact with novel items in their environment. To help reduce the risk of by-kill of kea during aerial 1080 pest-control operations, we investigated how kea perceive the different types of cereal baits typically used in such pest control.
One of the criteria for an effective bird repellent in a pest management context in New Zealand is that possum (Trichosurus vulpecula) and ship rat (Rattus rattus) kills remain high where repellents are used in poison baits. Repellents were used in baits applied within different treatment blocks as part of a large aerial 1080 operation in November 2013 near Haast on the West Coast of the South Island of New Zealand.
Concern about non-target risks to native birds, particularly kea (Nestor notabilis), from aerial poisoning has prompted the evaluation of potential repellent compounds that could be incorporated into the cereal pellet bait used for possum (Trichosurus vulpecula) and rat (Rattus spp.) control. Initial trials of d-pulegone and anthraquinone were not wholly successful, with the former having poor stability in bait and the latter reducing bait uptake by rats.
Intraspecific variation can have important knock-on effects on population dynamics and ecosystem processes. There are good indicators that intraspecific differences may exist in the foraging ecology of kea parrots (Nestor notabilis). Kea breed in two markedly different habitats (alpine and temperate rainforest), and have pronounced sexual size dimorphism of their upper bill, which may indicate niche partitioning between the sexes.