A couple of weeks back, dawn found me one hours drive down Scenic Route 72, passing the historic brick woolshed at Home Bush Station, boring through Glentunnel, humming through Wind-Whistle, hopping the drop into the Rakaia to skip and jump the dual gaps that squeeze this miles wide, braided river down to less than 100 metres wide. After climbing out on the south side it’s a down hill run past the Mt Hutt skifield entrance, over the Taylor River and North
Branch Ashburton River, around to Alford Forest where snow lingered not far from the road 0n the treeless hills.
With Mt Somers looming ahead Staveley Cafe is closed and dark so no espresso for this express. A little further is Mt Somers village and the turn-off for Lakes Heron and Clearwater, Mt Potts and Erewhon Stations and the Hakatere Conservation Park, gateway to the Arrowsmith Mountains. Next up is the South Branch Ashburton River followed by Mayfield. From Mayfield it’s a long haul toward an ever receding vanishing point under leaden skys of norwester tortured altocu and the passage of time marked only by the growing presence of Mt Peele and its prominent ridge. It’s a taste of Highway One south of Christchurch just quieter, narrower, bumpier and a lot less tedious with much better scenery.
Slowing for the Rangitata River the bed is choked with introduced weeds, pushed around by bulldozers and constrained by stop-banks (levees) that prevent the river developing its normal braided character.
Behind the stop-banks there are new water storage ponds (lakes really) to quench the thirst of dairy conversion on these dry stony plains.
A little further and I arrive in Geraldine, famous for ‘Barkers Elderberry Wine‘ and just the right distance from Kaikoura to be an overnight stop for tourists on their way to the McKenzie Basin and Mt Cook National Park. Geraldine will be my home away from home while I learn about wrybill, ngutupare (ngutu – lips; pare – turned aside) and tarapiroe, black-fronted terns the hard way, As part of the work around the “O Tu Wharekai” project I’ll be monitoring their breeding success on the Rangitata River.
These birds are endemic to NZ breeding only on the braided rivers where population decline is such that they are now largely confined to the eastern South Island rivers. They are joined here by a third braided river endemic, the black-billed gull, superficially similar to that mobber of seaside picnics and fishing wharves, the red-billed gull.
All three are in trouble and have been for some time. Top of the list of woes is habitat loss, by engineers forcing the
rivers into a narrow bed and by the damming of many of these rivers for
hydro-electricity; by an army of weedy introduced plants that occupy potential nest sites and stabilise the riverbed preventing the creation of new sites; and more recently increased extraction of water for irrigation making the rivers less suitable for nesting and less productive.
Next on the list is human related disturbance: dogs, motorbikes, 4WD vehicles and fishers oblivious to the mayhem they cause. Elsewhere in NZ I’ve encountered dog-walkers proud of how their dog “put up” the birds earlier.
Last but not least there’s the onslaught from all the introduced predators: cats, stoats, ferrets, weasels, ship rats and Norway rats and a surprise to most people is Mrs Tiggy Winkle and her prickly brood, who take eggs of any age and disrupt the breeding cycle. For those who don’t know the tale of Mrs Tiggy Winkle follow this link. O Tu Wharekai is seeking to find more affordable ways of dealing with these pests.