Distinctive noise calls for public to keep watch for rooks
Environment Canterbury media release: 9th January 2024
Keep your eyes and ears open for rooks especially in and around the Kennedy’s Bush area in south-west Christchurch.
We received a report from a concerned community member having heard a ‘kaah’ like bird call, which is often associated with rooks.
While they could not snap a photo of the bird, the iconic call was enough cause for the biosecurity team to investigate further. This follows two other unconfirmed rook reports from Parnassus in North Canterbury and Ashburton last year.
Biosecurity officers have undertaken surveillance around Kennedy’s Bush but urge the public to be on the lookout in their neighbourhood.
Overcoming rook threats
Rooks pose a serious threat to agriculture, wreaking havoc on newly sown crops at arable farms, ripping them out and damaging small plants.
The last known lone rook was shot in April last year by a farm worker in North Canterbury’s Parnassus/Inland Kaikōura road area after a year of various sightings in North Canterbury, declaring eradication a success.
Reducing rook numbers was no small feat, with peak numbers reaching 5550 birds in the early 1990s, predominantly in Banks Peninsula, Selwyn and Timaru. Rooks are notoriously difficult to control as they are very intelligent and fast learners, quickly dashing traditional control methods.
However, small populations of birds still exist in Marlborough and Otago, and there was always a risk they could re-enter given their tendency to travel to breed.
How to identify rooks
Rooks are members of the crow family and are glossy, purplish-black with a light grey featherless face and a dark grey beak.
Larger than a magpie, they generally weigh about 400 grams and are around 45 centimetres long.
Report any rook sightings online or contact Environment Canterbury immediately on 0800 324 636 and take a clear photo if possible. Do not approach them as they are wary of people and will leave the area.