Helicopter operations targeting rooks are taking place in Cambridge, Matamata and Mangakino over the coming week.
Rooks are large, black birds, native to Great Britain and Europe, which pose a serious threat to our agricultural industry. They feed on and damage newly sown crops, tear up pasture in search of seeds and grubs and rip open silage covers.
Environment Waikato is trying to keep rook numbers low to protect our region’s farms.
There are an estimated 100-200 rooks in the Waikato, with rookeries (clusters of nests) located in the northern Hauraki Plains, Cambridge/Matamata, north Waikato and Taupo areas.
Controlling rooks in the Waikato region is tricky work, because they nest high in the branches of tall trees, where they can only be reached by helicopter.
“They’re very intelligent, cunning birds – they can recognise people and vehicles and they’ll fly away as soon as they see you,” Environment Waiakto biosecurity officer Dave Hodges said.
“When we first started controlling them they were nesting in lower branches, where we could reach them using ropes and ladders. Now they nest high in the canopy and they’re starting to stagger their breeding, which means we have to visit nests several times.
“Shooting is not a feasible control method because you’ll only get one bird before the population scatters and fragments, and when a group of rooks disperse they can be quite hard for us to find again.
“For this reason we would rather landowners did not attempt to control the birds themselves – if you see one please call 0800 BIOSEC (0800 246 732).”
Otorohanga-based pest control company EcoFX Pest Solutions has been carrying out rook control on Environment Waikato’s behalf this breeding season, which began in August. The third and final round of control is scheduled over the next week or so, depending on the weather.
To reach the nests, EcoFX pest control officer Kahn Adam, from Te Awamutu, hangs from a long chain attached to a helicopter.
Mr Hodges said while Environment Waikato had managed to reduce rook numbers in the region, the council may never be able to get rid of them completely.
“Other regions have much larger rook populations and we can’t stop them migrating here, but it’s important to keep the numbers manageable because they are a major production threat,” Mr Hodges said.