in praise of wetlands
Wetlands – a boyhood playground, a national treasure
I’ve always loved wetlands – though when I was a kid we called them swamps. Wetlands is a term I learned as a young adult, and it was not until then that I really learned to appreciate, from a scientific point of view, the biodiversity treasure that wetlands represent.
Swamps, on the other hand, seemed in my early years to be a more derogatory word. The adults of my childhood days seemed generally to regard them as places to be avoided or drained and turned into something “useful” such as pasture. Swamps were “waste ground”; I can think of a half dozen places in my home district where wetlands were used as dumps. The only creatures to benefit were rats and the feral cats that fed on them. Most of these dumps were illegal, but some were official, largely unmanaged, landfills. Thankfully, council practices and public attitudes have changed for the better.
But for me, a swamp has always been a place of mystery and wonder, full of smells, sounds, creatures and plants that provided a small boy a natural adventure playground that has never lost its appeal.
The wetland that dominated my early years was simply called “the swamp”. It needed no other name. This was on the shore of Lake Clearwater, in the Ashburton Lakes District in the South Island high country of New Zealand. The district is now recognised as a nationally significant wetland and comprises much of the Hakatere Conservation Park.
My parents had purchased a bach (a uniquely Kiwi expression for a very basic holiday cottage built on a tight budget) on the small ribbon of land between Lakes Camp and Clearwater. In those days it was not conservation land. The district council administered the area encompassing the baches, and beyond that was pastoral leasehold land controlled by the high country run-holder. There was a narrow riparian nature reserve around the borders of the lakes.
“The Lakes” were an angler’s paradise, notable for the quality of fly-fishing particularly. But for a boy with a love of the outdoors and nature, a vivid imagination and a longing for adventure, they were a summer playground; a place where children could, for a few weeks, live a Tom Sawyer existence of rafts, eeling, bully fishing, swimming and tree-hut building. Hide-and-seek (our variant was called ‘kick the tin’) was played amongst thick tussock and matagouri (Discaria toumatou) scrub. Skinny-dipping raised barely an eyebrow.
All wonderful stuff, but for me the mystery of the swamp was king. A large red-tussock (Chionochloa rubra) and pukio (Carex secta) wetland, it was treacherous in places, with deep holes that could suck a kid down no trouble at all. Indeed, I remember plunging up to my armpits in thick swamp mud, with no bottom within reach of my toes, before my father lunged for my shirt collar and managed to extricate me only through the strength that comes with adrenaline-fed panic.
The mushroom-shaped pukio swamp tussocks were as tall as me, creating a labyrinth of channels, pools and backwaters shaded by their shaggy heads. In summer, vivid green mats of semi-floating swamp grass, grazed to an almost bowling green consistency by the Canada geese (Branta Canadensis) and putangitangi (paradise shelduck – Tadorna variegata), sprouted masses of tiny purple orchid-like flowers. Where it wasn’t quite so wet, white alpine gentians (Gentiana patula) flowered profusely. We used to love teasing visitors by telling them the root was edible. It was, but it tasted absolutely foul!
The kahu (Australasian harrier – Circus approximans), appropriately also known as the swamp harrier, was an iconic species here, gliding long and slow over the tussock tops before plunging quickly on birds’ eggs or chicks, lizards or other small prey. It was frequently seen scavenging road-kill rabbits.
The karearea (New Zealand falcon – Falco novaeseelandiae) was a faster beast, striking in swift dives at birds driven into the shelter of matagouri for protection, flushing panicking birds out of the safety of the thorns into the clasp of their talons.
In the shallow waters of the lake the rare and threatened Puteketeke (Australasian Crested Grebe – Podiceps cristatus australis) built floating nests among the willows. They were joined on the water by rafts of papango (New Zealand scaup – Aythya novaeseelandiae) and the ubiquitous ‘parries’, plus hundreds of introduced game birds such as Canada geese and black swan (Cygnus atratus).
Amongst the matagouri, bright green beetles glistened iridescently. The dry-fly imitation was effective at enticing trout from the lake. Skinks rustled through the tall grasses and, on the drier banks, gecko sunned themselves on rocky outcrops. Dragonflies and damselflies raced over the water, sometimes in such numbers that the trout were driven into a feeding frenzy! I recall a day in one of the swamp’s muddy bays, the lake as still and clear as glass, when a huge damselfly hatch was occurring. A cast fly quickly attracted dozens of damselfly, which saw the floating imitation as a handy perch just above the water. Huge trout cruised the shallows, ignoring single flies (imitation or real), but chomping greedily on those living bundles of mating damsels. I caught my bag limit of trout that day!
High overhead both the native pihoihoi (New Zealand Pipit – Anthus novaeseelandiae) and the introduced skylark (Alauda arvensis) spangled their trilling songs from a clear hot sky, or they hopped along beside us watching for the insects we would disturb.
In the shallows bullies skimmed across the muddy lakebed, dragonfly larvae hunted caddis fly larvae and tadpoles and, in turn, were scooped up by the voracious trout. Occasionally, a rare and threatened giant kokopu (Galaxias argenteus), the largest of the galaxid species that make up the annual whitebait run, could be seen lurking in the shadows of the deep swamp-water channels.
Then, cattle were allowed into the swamp and sometimes camped there, turning patches of it into dung-filled mud holes. Thankfully, those days are over and the status of conservation park protects the unique ecology of these high country tussock wetlands.
While I do not get back to “The Lake” near as often as I would like, my passion for wetlands remains.
In the Wellington region, where I now live, two wetlands, in particular, provide endless hours of pleasurable strolling and bird watching. One is the Pauatahanui Wetland at the head of the Porirua Harbour, a mixture of tidal mudflats, salt and freshwater marshes. Further north on the Kapiti Coast is Waikanae Estuary, which offers large sandbanks used by nesting birds, braided tidal mudflats and extensive scrublands. In these two wetlands alone I see an impressive list of birds.
Among my favourites are the glorious kotuku-ngutupapa (royal spoonbill – Platalea regia), the tiny pohowera (banded dotterel – Charadrius bicinctus) and the swift tara (white-fronted tern – sterna striata). The delicate poaka (pied stilt – Himantopus himantopus) is another year-round regular. The occasional rare (in New Zealand) kotuku (white heron – egretta alba modesta) and the endemic and highly threatened ngutuparore (wrybill – Anarhynchus frontalis) are winter visitors. In spring, seasonal migrants such as kuaka (bar-tailed godwit – Limosa lapponica) fly in to the mudflats, and the rare caspian tern (Sterna caspia) arrive on the sandbanks to begin nesting. There are many other birds I have not listed that also frequent these precious wet places.
Thankfully, the old attitude to wetlands has substantially changed as we have become more aware of the importance of these environments as host to a whole range of species, many endemic to New Zealand and rare.
At both Pauatahanui and Waikanae volunteers from organisations like Forest and Bird work hard to replant these areas, kill invasive introduced weeds, protect the water quality and set trap-lines for introduced mammalian pests such as rats and stoats. At Lake Clearwater the protected status of the tussock swamps is preserving a host of rare plants and increasing the chances of breeding success for the crested grebe.
With a huge percentage of New Zealand’s original wetlands destroyed, these remaining swamps, marshes, estuaries and mudflats are not only a birder’s delight, they are a national biological treasure.