Predator pests face a terminal future
It’s important to know your enemy, especially when your targets are slippery characters like rats and possums.
On that count, Karen Barlow is an expert as she dishes out advice on a new initiative to trap predator animals around a gully near the Hamilton Airport.
Barlow is the community coordinator for the Predator Free Mystery Creek Hub which aims to support efforts to control ferrets, weasels, stoats, rats and possums, to name a few.
Hamilton Airport staff were granted some time with Barlow to learn how to trap rats and possums. In the morning, the group constructed 79 rat trap boxes at the Mystery Creek Events Centre, which neighbours the airport.
In the afternoon, Barlow showed the group how to set the traps around the gully, which is a few hundred metres from the terminal, behind Jet Park Hotel.
Each trap was geo-tagged using the Trap NZ app which would make it easy to find the traps for weekly inspections. Barlow also provided possum traps which were set 100m apart while the rat traps were about 50m apart.
‘‘Rats are neophobic which means they don’t like anything new,’’ Barlow said. ‘‘So these traps may sit here for about three weeks until they get used to them being part of their environment.’’
The staff volunteers were told to ‘‘scuff up’’ the ground around the traps to make it look like other animals had been foraging for food, to entice the rats to investigate the trap.
‘‘Rats are not put off my human scent because when they smell humans they know there is food around and shelter.’’
A teaspoon of peanut butter was used as bait on the springloaded rat trap. The trap is then put into the rat box.
‘‘Peanut butter is good because it has oil in it which means it lasts
Predator Free Mystery Creek Hub longer,’’ Barlow said. ‘‘Meat is good too but it doesn’t last long and it dries up. So the fresher your bait, the better.’’
Barlow said rats will eat each other and it wasn’t uncommon to find half a rat left in a trap, with the balance probably serving as a takeaway meal for others.
Rats are also extreme breeders. One pair can breed five times a year and have eight babies each cycle.
Possum numbers were also high and Barlow said there were 40 million in New Zealand. Trapping possums required a different level of enticement.
Barlow used halved apples smothered in icing sugar and flour because they ‘‘like to eat sweet things’’.
The traps were white, the colour possums were attracted to. The rat traps were set on the ground but the possum traps were set higher, on posts or trees, to eliminate the chance of domestic cats wandering in.
Icing sugar was also used as a trail down from the trap along the ground.
Rats are a problem because they are good climbers and able to access birds to eat high in trees. On the ground they eat lizards and eggs. Possums compete with native birds and reptiles for food but also raid bird nests to eat eggs and chicks.
Reducing the number of predators would help their food supply and provide safer nest sites.
Barlow and Hamilton Airport chief executive Mark Morgan were keen to see what the results would be in two or three months.
‘‘Rats are not put off my human scent because when they smell humans they know there is food around and shelter.’’