Wild in the City part II – The Groynes
Christchurch New Zealand is blessed with a variety of places within the city boundaries where pockets of wildlife, especially our birds, continue to thrive. I’ve decided to feature these places in a series. This is the second.
The dictionary defines a groyne as a wall or jetty built out from a riverbank or seashore to control erosion, and it is just such a prosaic structure that has given its name to one of Christchurch city’s wild treasures, The Groynes Park.
The area now occupied by Christchurch was once part of a vast wetland of rivers and streams, artesian springs, swamps, small lakes, grasslands and native forest that abounded with life, especially birds.
With the arrival of European colonists came drainage for farming and settlement and the ‘taming’ of rivers within stop banks. As a result, nearly all that wetland has gone save for a few precious small and isolated remnants. The Groynes, though highly modified with exotic planting and groomed parklands, are one such remnant.
The groynes themselves were made from concrete-filled woolsacks. The sacking has long since rotted away leaving these squat, odd-shaped ‘bales’ around which surge the clear waters of the spring-fed Otukaikino Creek.
Along the borders of this creek has been created The Groynes Park. Weirs and excavations have created a series of long pools and small lakes and low falls that spill through a large area of exotic plantings, mostly poplars and willows, mixed with remnants of native forest. In spite of the large groomed lawns for picnickers and sport, and the manicured banks of the artificial lakes, much of the Groynes has a wild feel to it. Trees grow thick and un-pruned, the water is dark in their shadow and blackberries, bracken fern and ivy run rampant through the undergrowth, making progress all but impossible except on the designated paths.
Now, the landscapers have gone full circle. Their predecessors removed the forest and drained the wetlands, replacing kahikatea, matai, toetoe and harakeke with pines, eucalypts, alders, hawthorn, rowan and cotoneaster. Today’s gardeners are re-planting the native species and restoring marshy wetland; their long term vision to see the return of some semblance of the rich Canterbury plains wetlands with their tall swamp forest trees and associated wetland species (plants, birds, fishes, reptiles and insects).
What is wonderful is that this eclectic mix of exotic and native plants sited in a blend of natural and human-created landscapes, is home to a remarkable array of animals, especially birds. In this world, too, exotic rubs shoulders with endemic. The European song thrush and blackbird root through the forest floor while a metre or so above their heads piwakawaka flit around, picking up the insects the larger birds have disturbed into flight.
The tiny silver-voiced riroriro cares not whether it hangs its nest from the flimsy limbs of a juvenile kowhai, or among the protecting spines of the hawthorn. Kuruwhengi glide across the ponds alongside introduced mallards, though the native bird distains the offerings of bread from visiting children that the mallards greedily devour. With re-vegetation of native species continuing, this mix of native and endemic species is continuing to develop.
On any given day the park rings with the joy of recreating humans barbecuing, playing ball, kayaking on the lakes, walking their dogs and fishing from the ponds. And, right beside them, the bird photographer can delight in a list of species that is impressive for a green island on the edge of a large urban environment.
On the water the native species include kuruwhengi (Australasian shoveler), tete (grey teal), papango (New Zealand scaup), black swan, coot, kawau (black shag) and kawaupaka (little shag).
Flitting over the ponds’ surface warou (welcome swallow) can be seen and kahu (Australasian harrier hawk) patrol the skies.
Pukeko wade the edges of the streams, kotare (sacred kingfisher) spy down from overhanging branches, and kereru (New Zealand pigeon) pluck the tender shoots of kowhai and willow alike. A lone koitareke (marsh crake) – ultra secretive birds – has also been reported.
The native forest birds include riroriro (grey warbler), piwakawaka (fantail), tauhou (silver eye), korimako (bellbird) and, in the spring, pipiwharauroa (shining cuckoo).
Rare native bird visitors include karearea (New Zealand falcon), matuku (Australasian bittern) and kotuku (white heron).
Three species of gull also visit The Groynes, including the black-billed gull, which is endemic to New Zealand and the most endangered gull species in the world.
Their exotic companions include mallard, domestic geese and ducks, Canada geese, redpoll, chaffinch, goldfinch, greenfinch, sparrow, dunnock, blackbird, thrush, Australian magpie, feral pigeons, starling, yellowhammer, cirl bunting (an uncommon and visitor) and skylark.
The objective for future plantings is to contribute to and maintain the park’s historical features, maintain wide open spaces and create new variable sized spaces, enhance the ecology of the riparian edges, and provide native habitat and ecological interest. This will improve ecological values and recreation for future generations.