Predator Control

April May 2001 saw the first intensive rat control programme installed on Kotuku Peninsula partly financed by the Auckland City Heritage Fund. Rat bait stations were installed on a grid of 100m x 50m across the two valley catchments of the Tony and Mal Bouzaid property at Glenfern in Port FitzRoy.

Two weeks were allowed after all the 190 bait stations were installed for the rats to become used to this intrusion in the landscape before bait was inserted. Pestoff brodificoum pellets were used to fill each station and two weeks later refilled again as all the bait was taken. After the second baiting the bait take dropped off rapidly and dead rats were apparent on all the lines. Some gullies smelled heavily of dead rats. After the third baiting the pellets were switched to Pestoff blocks secured on the bait station pins and monitored monthly.


The effect on birdlife was immediate with the smaller birds; fantails, grey warblers and kingfishers recovering dramatically in the first year judged by bird counts taken.
In 2002 Orama Christian Fellowship Trust received a grant from Auckland City Heritage Fund to install a grid of rat bait stations throughout the properties on the other side of the peninsula as far as Kotuku Point. Wayne assisted Phil Thomson to cut the transits this time set on contour lines. The terrain is steeper than Glenfern with heavily inundated ridges and gullies. The mainly short tight manuka had to be cut with a chainsaw to install the 250 bait stations. Two further lines ran out to Kotuku Point and down the Telecom line ridge forming the north eastern boundary.


The same year lines were cut on contours between the valley catchments and the Kotuku Scenic Reserve boundary adding a further 80 bait stations to saturate the Glenfern area.
In 2004 a further three transits were marked throughout Kotuku Scenic Reserve from the shore to 50m below the P line ridge. These were baited with a 1st generation anticoagulant Racumin to meet the requirements of the Department of Conservation permit. As the rats had to have multiple feeds of this bait for a lethal dose these stations were monitored on a two weekly cycle.


With the whole peninsula now covered with a lattice of bait stations three tracking tunnel lines were installed across Kotuku Scenic Reserve and from Glenfern Sanctuary into the Orama catchments to monitor and provide an index of rat density. This regime has continued until winter 2008. With the completion of the pest proof fence the whole peninsula will be baited with Pestoff for three months and then the bait removed until the eradication planned for July 2009.

Tony Bouzaid