Back in September last year I did a post “On the way to O Tu Wharekai” it was hasty, photos weren’t so good and I fully expected to quickly find out what was meant by O Tu Wharekai and let you know. Well it only took 7 months to get to the bottom of, and then I did literally, crutch deep in stinking mud and slimy water (sorry no photos, much too busy extricating self).
Now I had an idea that O Tu Wharekai had something to do with food – the wharekai on a marae is the dining hall, but I couldn’t see the fit for Tu. Capitalised ‘Tu’ is usually an abbreviation for Tu Matauenga the god of war and just plain ‘tu’ is to stand or often to ‘take a stand’ or a fighting stance. It finally became clear recently when I got to stay a few nights at the Hakatere huts and had the leisure to read the information panels there (no pub, no telly, no phone, no cell cover, definitely no internet).
Turns out O Tu Wharekai is the Maori name for the lakes which on the maps are called Maori Lakes and they were a very important area for food gathering for the Maori of South Canterbury. As well as being an important area for waterfowl: grey duck, brown teal, scaup and shoveller they hold a huge resource in eels and kuku (freshwater mussels). These days the brown teal are gone but there is a good population of Australian black swan and these high country lakes are very important for crested grebes. The Maori Lakes were also on one of the greenstone trails linking the southern and central eastern South Island with Hokitika on the West Coast via the Rakaia River and what we now call Whitcombe Pass, a place to prepare for or recover from the mountain crossing. O Tu Wharekai has in turn been adopted by the Department of Conservation (DOC) for the ambitious wetland restoration/conservation project I’ve been part of for the last 9 months.
It comes under the Arawai Kakariki programme as one of three core wetland projects in the country (ara-path, wai-water, kakariki-green: greening (restoration) of the waterways). This is the only project to incorporate entire catchments, the other two are more what you might expect, the huge Whangamarino wetland in the Waikato and the Awarua-Waituna wetland on the south coast between The Catlins and Bluff.
The O Tu Wharekai project encompasses the catchments of the Rangitata River and the South Branch of the Ashburton River (Hakatere). It’s unusual in that while there is a lot of public land managed by DOC, that land is fragmented and a lot of the important land (e.g. riverbeds) is managed by other agencies who are at best indifferent to biodiversity values.
Further a big chunk of the land is in private ownership for farming or under High Country Grazing Lease in Perpetuity and a lot of those farms have tenure to the middle of the river(s) which means stock in the waterways and nutrient rich siltation of lakes such as Maori Lakes which were shallow to start with. By now you start to realise that maybe that Tu is not so out of place; to succeed this project requires making a stand, convincing farmers to change their practices at a time when intensification and irrigation are seen as the way forward and getting those other agencies to start taking biodiversity seriously. Not forgetting there is a fight going on of sorts: 500 odd kill traps strung out down both sides of the Rangitata to give the birds a chance against the introduced mammalian predators, and two community led trapping programmes in the Hakatere, which surely comes under the domain of Tu Matauenga.
Now that thing I was doing that got me to the bottom of O Tu Wharekai was a pest fish survey, the main concern here is rudd and Gambusia (mosquito fish), but there’s also a possibility of catfish, koi carp, tench, goldfish and perch. Perch are already here but so far only in two lakes and sadly mosquito fish do not control mosquitos, at least not in natural waterways. Dyed in the wool environmentalists would add trout and salmon to the list, “AQUATIC STOATS”, the analogy is a good one, particularly for trout, but as a game fish worth millions of $$ to the NZ economy through tourist anglers, the topic is taboo. Most of the ‘pest’ fish wreak havoc on the waterways they get into, they muddy the water by stirring up the sediments but they also cause massive changes in the plant-life, nutrient cycling and native species present.
In the normal course of things powerboats are not permitted on the Lakes in this area (except Lake Camp) and no form of boat is permitted on the Maori Lakes. We were able to get an exemption while we carried out the survey.
There were bladderworts in flower,where we dragged the boat about, ‘enough of that!’ the skipper muttered ‘lets get this boat afloat’
So we puttered on Lake Emma
And we rowed on Maori Lake
To lay out Fykes on stakes
And hang up Minnows by the dozen
The parries were not happy
And the swans all took to flight
We saw where they had fertilised, the raupo in the night.
And a dragonfly or two
A single lonely koaro
And yards of long finned eels
We netted several nice brown trout (alas to be returned) #
Tucked up in Harrison’s Bight
It came as a surprise to find the eels had, had themselves a bite
A lecherous wee fella, went out into the night looking for his dinner£
Dan from Perth, Ontario came out for the wildest day
# Lake Heron is renowned for its fishing with brown and rainbow trout and pan-sized Atlantic salmon. With high numbers of diving birds we were required to monitor gill-nets and that gave us the opportunity to release all trout and salmon soon after they were caught.
£ Leeches are rarities in NZ, in fact this is the only one I’ve ever seen, most waterways don’t have them.
No pest fish were found during this survey.
Further Information on O Tu Wharekai