Wetlands & riparian zones

Wetlands and waterways are a critical part of any farm and they provide important habitat or seasonal resources for a range of valued and diverse wildlife, such as waterfowl and other birdlife, fish, eels, and bees. However, they are also havens for introduced predators and their impact on wildlife can be devastating. Your control will need to target the following three types of predator:


Possum control

Option 1 

  • Night-shoot wetland willows as bud-break occurs in spring. Shoot on 3 or 4 nights over a 2–3 week period. Warm nights are best, especially after rain. 
  • Follow up with kill traps (Timms or Sentinel) at 100–150m spacings along the inside of wetland and/or stream margin fence-lines. 
  • Service and re-bait traps every 2–4 weeks, depending on the population
Royal Spoonbills (Platalea regia) in a wetland
Royal Spoonbills (Platalea regia). Image credit: istock.

Option 2 

  • If pigs are not present, use bait stations 30cm off the ground at 150m spacings on trees, well away from stock access along the inside of fence-lines. 
  • Use Pestoff Brodifacoum possum baits in Philproof ‘mini’ bait stations. 
  • Pulse 700g of bait initially and then 300g of bait per station every 4 weeks from late winter (August) to early spring (until late October). 
  • Where there are ‘non target’ species at risk, use 2–3 applications of Feracol or DECAL over the same period, pre-feed with the equivalent non-toxic product for one week before each toxin application. • Both of these products will also control rats. 
  • ’Double Tap’ pellets are a combination of Cholecalciferol and Diphacinone that can also control rats and possums with reduced non target risks. 
  • Ensure dogs and livestock CAN NOT access any bait.

Rodent control

Traps

  • Goodnature A24 automatic resetting traps are ideal. Locate at 75–100m intervals about 10–20cm off the ground on trees away from stock access along the inside of fence-lines.
  • Replace CO2 gas canisters and lure pumps about every 3–4 months. 
  • Rodent snap-traps can also be used (they are cheaper). Place in small wooden tunnels set up in a similar way to A24 networks. Lure with peanut butter. Check regularly every 1–4 weeks.

Bait stations

Cut through view of a filled bait station. You can use bait stations in wetlands
Cut through view of a filled bait station. Image credit:
  • During times of higher rodent populations, bait stations may be more effective. The same network of bait stations as for possums can be used, but extra traps or stations may be required in between to reduce spacing to 50–75m. 
  • Pulse with Pindone pellets, Ditrac, Contrac or Pestoff (blocks or pellets) monthly, from August to November.
  • ’Double Tap’ pellets are a combination of Cholecalciferol and Diphacinone that can also control rats and possums with reduced non target risks 
  • Ensure dogs and livestock CAN NOT access any bait. Note: Possums can eat large amounts of Pindone pellets. If you have a CSL then Feratox (encapsulated cyanide) is a good product to reduce this, or place kill traps at bait stations

Note: Possums can eat large amounts of Pindone pellets. If you have a CSL then Feratox (encapsulated cyanide) is a good product to reduce this, or place kill traps at bait stations.


Mustelid control

  • Use DOC 200 wooden box traps with enlarged openings (4×4 mesh squares) to target weasels, stoats and ferrets. 
  • Place away from stock access at 100–150m intervals along the inside wetland and/or stream margin fence lines. 
  • Rebait about every 2 weeks with eggs, fresh rabbit (in winter), or Erayz rabbit blocks/paste (a long-life product) in warmer climates. Rebait less in winter and more in spring/summer. 
  • DOC 200 traps also catch rats and hedgehogs. 
  • Modifications may be required if kiwi, weka or other non target species are present.

For more information on predator control specific to your area, we recommend that you contact a predator control expert, your regional council or local DOC office.

Small ferret caught in a DOC 200 wooden box trap. You can use traps in wetlands
Small ferret caught in a DOC 200 wooden box trap. Image credit PFNZ Trust.

For more information

For more information on predator control specific to your area, we recommend that you contact a predator control expert, your regional council or local DOC office.