non-target effects

When meat baits containing PAPP are applied in bait stations in field settings, stoat and feral cat numbers can be rapidly reduced. However, there has been limited practical experience with PAPP to date, especially when compared with alternative tools such as traps or sodium monofluoroacetate (1080) baits. Additional practical experience should enable the effective use of PAPP as a tool to help protect native species from introduced predators. In the future, PAPP will be developed in long-life bait and in a resetting toxin delivery system.

The application of fensulfothiqn and parathion for the control of invertebrate pasture pests in Canterbury during March, April and May 1970 killed many birds and mammals. Two hundred and thirty-six dead birds were found after a single application of fensulfothion to 123.4 ha, and 158 birds were recovered from 78.5 ha of pasture treated with parathion. The main species killed were white-backed magpie (Cymnorhina tibicen), black-backed gull (Larus dominicanus) and harrier hawk (Circus approximans).

Zinc phosphide (Zn₃P₂) has been used overseas as a vertebrate pest control tool for several decades. It has been favoured in the USA and Australia for the field control of rodents and other animal pest species because of its comparatively low risk of secondary poisoning and lack of environmental persistence. Zn₃P₂ paste was approved for use as a possum control agent in New Zealand by the Environmental Protection Authority in August 2011.

Invasive weeds have been shown to alter ecosystem processes such as decomposition and nutrient cycling. However, little is known about the effects of introduced biocontrol agents on these processes. This study examined the effects of alligator weed (Alternanthera philoxeroides) and its biocontrol agent, the alligator weed flea beetle (Agasicles hygrophila), on nutrient cycling in a northern New Zealand lake.