Rook populations at all time low

Rook populations in the Region have reached an all-time low with a 9.2 per cent reduction in the number of nests after ongoing aerial control by Horizons Regional Council.

Rook populations in the Region have reached an all-time low with a 9.2 per cent reduction in the number of nests after ongoing aerial control by Horizons Regional Council.

Since the inception of the Region-wide aerial baiting programme in 2005 the number of active nests has reduced across the Region by 94 per cent from 2,942 nests in 2005 to 188 nests in 2015. The number of active breeding rookeries across the Region has dropped from 84 to 69.

Manager of biosecurity and habitat protection, Bill Martyn, says the programme has been incredibly successful since its inception in 2004.
“The programme has seen rapidly declining numbers and the results in Tararua are particularly excellent,” he says.

“Rooks in our Region were heavily concentrated in Tararua due to accessibility to cropping and the climate. We’re pleased to report that the reduced numbers in Tararua are on par with the low levels shared across the Region.”
Regional results from 2005 onward show Taihape with a 94 per cent reduction from 476 nests to 28 nests, Manawatu with a 67 per cent reduction from 101 nests to 33 nests, and Tararua with a 95 per cent reduction from 2,365 nests to 127 nests. 92 per cent of the rookeries were relatively small. The two largest rookeries were located in the Rangitikei District near Rewa and in the Ruapehu District north of Raetihi.

The aerial nest baiting programme was undertaken in October 2015 and involved poison being placed directly into nests by helicopter.

“Some of the credit for the success in Tararua is due to collaboration on district boundaries between Hawkes Bay Regional Council and Greater Wellington Regional Council,” says Mr Martyn.

Rooks are classed as an animal pest in the Horizons Pest Management Strategy and when left unchecked can create issues of crop damage for farmers.