In the third article on how Maketū Ōngātoro Wetland Society (MOWS) rescued Waihī Harbour Wetland, society chairman Julian Fitter looks at the current situation, and the future.
Previous articles have talked about the problems and success of the first seven years of this ecological restoration project.
I want to turn to what we have now and how we are going to build on that.
Isaiah 57:21 says, "There is no peace for the wicked," but in reality, when it comes to environmental restoration, restoring the mauri, there is no peace for the righteous either.
Once you think you are on top of one pest, another one appears, or maybe two. This is in part because in Aotearoa New Zealand we have a very attractive environment for new species and we have few natural controls available as our wildlife evolved in isolation.
The Waihī Harbour Wetland has come a long way in seven years and we can count a number of successes:
■ Matuku, Australasian bittern: NZ Bird of the Year 2021, arguably the best site in the BoP for this threatened species, we had at least two nests last season.
■ Banded rail: known breeding site and excellent habitat in both sections of the reserve.
■ Spotless crake: known inhabitant seen regularly, hard to locate the nests but they must be breeding.
■ Fernbird: regularly heard, and occasionally seen, certainly a breeding population.
■ Royal spoonbill: a flock of 40+ are resident, no clear evidence of breeding, though they do develop filoplumes in the spring, generally seen as "breeding plumage".
■ Duck: shoveler and grey teal breed here on a regular basis.
■ Waders: the mudflats of the harbour are ideal habitat for waders, pied stilt breed in the reserve and are present all year round, as are variable oystercatcher. Southern pied oystercatcher and bar-tailed godwits are migratory and are present in our winter and summer respectively.
■ Shore skink and copper skink; both at risk, declining, and both found here in the western section.
■ Native musk; at risk, naturally uncommon. An attractive wet-loving plant found in the freshwater section of the reserve.
■ Convolvulus hawk-moth breed in the reserve, watch out for its large 75mm long caterpillar with a hooked tail.
While some of these species were there when we started, all have benefited from fewer animal predators, fewer weeds and more native plants. However, as a site connected to farmland, we know we will have to keep it up for the foreseeable future.
Native plants are obviously a key part of any restoration project. Here we have done a significant amount of planting in the western section, but in the east, we have just controlled the weeds and allowed natives to spread naturally. This has so far been extremely successful.
One unusual and interesting native plant we do have is the native musk Thyridia repens, a low spreading plant with attractive purple flowers that likes the very wet areas that are flooded from time to time.
This means we do need to keep an eye on the water level within the freshwater wetland.
Two other important plants are from the Bolboschoenus family. Along the river banks we have B fluviatilis and inside the freshwater wetland, some B caldwellii. We have already started using B fluviatilis as erosion control along the Pongakawa, and we may find that B calwellii can be used to similar effect.
Interestingly they are perennials with substantial root systems, the leaves die off in autumn, which enables us to spray out any unwanted grasses or weeds. So wherever we can, we will look to use native plants as the whole, or part of, the solution.
Most of our early plantings in the reserve were old favourites; taupata, ngaio, akeake, flax, hebe, karamū and karo. We did later add a few kahikatea, tōtara, lancewood and karaka and also tried adding some ferns.
Now we need to make a concerted effort to broaden the range of species so we have a more natural mix of plants. Adding plants like pūriri, rewarewa and fivefinger will help attract birds such as kererū. We have already had one record of a korimako.
One area we have not yet delved into is invertebrates. Invertebrates are as important as native plant species in providing the basic ecology for higher animal species to survive.
When we started out, most of the plants in the reserve were aliens, and so the number of native invertebrates would have been low. However, after seven years, our plantings provide significant habitat for native invertebrates, so this is probably an area we should be looking at developing soon.
The Main Pests
Mammals: we have pretty much the full range, cat, ferret, stoat, weasel, rat, and hedgehog. Ongoing control should keep numbers down and allow native species to prosper
Reptiles: while we have two species of native skink, we also have the rainbow or plague skink, introduced from Australia. These are a serious threat because they multiply very rapidly. While our native skink is viviparous and gives birth to live young, the rainbow skink lays eggs, a dozen or more at a time. Two years ago I found around 100 plague skink eggs under a DoC 200 trap, laid by several females. As I watched, young skink started hatching from the eggs.
Controlling skinks is not easy, especially when there are native ones around as well. The standard method is the pitfall trap, however, these need to be checked at least every 48 hours, so use a lot of resources, and you need a lot of traps to be effective.
Weeds: We are very much on top of the ones that choked the wetland back in 2015 - wattle, pampas, gorse, broom and bramble. We still need ongoing control, but they are no longer an ecological threat.
The new weeds are Glyceria, an invasive grass, cow cress, a large celery-like weed that blocks the drains and can be very dense along the stream banks, sea couch around the harbour margins, and willows – we have removed some of the willows, but there are still significant numbers in the southeast of the reserve. These four are our main targets. In addition, we have a real problem developing with the native mānawa or mangrove, which has spread significantly and is starting to threaten the saltmarsh, a key habitat for most of our threatened species. The control of this plant, albeit a native, will be key to our being able to restore the mauri of the site.
No individual wildlife site can be protected and restored in isolation, even putting a pest-proof fence as at Maungatautari does not stop all intrusions, but the larger the area you are looking after, the easier it is to protect the core.
It is therefore very good news to know of two developments that will help to support and protect the work that we are doing in the Waihī Harbour Wetland.
The first is the Wai Kokopu project. This restoration project covers the whole of the catchment of the Kaikokopu and Pongakawa Streams and will involve a lot of work protecting stream margins, reducing agricultural runoff, with much less erosion and therefore less mud and silt in the harbour.
The other is the development, linked to Wai Kokopu, of an iwi group looking to work in the harbour itself and in the very large Waewaetutuki Wetland adjacent to our wetland, between it and the Maketū Bluff.
The task we have ahead is very significant; it is not something that can be done by volunteers on a Sunday morning, or indeed by volunteers every day of the week.
The requirements of modern health and safety regulations, the need for machinery and sophisticated equipment, mean that the days of the purely voluntary group are numbered.
If you want to really make an impact, you need to get in there on a professional basis.
MOWS saw this at least 10 years ago. While we need and encourage volunteers, it is inevitable that much of the work must be done by trained and paid employees.
We initially started off using members on a casual contract basis, but in 2020 we realised that we had to change gear and so took on our first full-time employee. We now have four full-time employees, and it does make the project management a great deal easier and ensures that the work gets done.
In line with this, MOWS, in 2018, was a founder member of the Bay Conservation Alliance. Starting out with just four member groups, we now have 23.
BCA has received funding under the Jobs for Nature programme to run a series of 12-week conservation work training courses.
We started cohort five this week with cohort six starting in September.
If we are going to make progress, we need people trained to do the work, with knowledge of the environment, who can identify weeds, and who understand the ins and outs of trapping and pest control. With good training, you can do more harm than good.
MOWS and BCA also run a rapidly expanding education programme. The programme is structured, year-round, and will this year expand to include 15 schools, primary, intermediate and secondary, with additional education days provided for a further six schools.
This key programme, which should surely be funded by our Ministry of Education, is in fact funded by WBOPDC, TECT and BayTrust. At least someone appreciates the importance of this programme.
The environmental knowledge of the average Kiwi is quite frankly abysmal. We talk a lot about our environment, clean green etc. but many cannot distinguish between the graceful native toetoe and the invasive alien pampas.
It is sad to see pampas spikes being used by florists and others. You cannot be a kaitiaki if you do not know your environment.
Knowledge is power. With this knowledge, you can see and understand the problems. Without it, you are blind and incapable.
If we are to win, not just the local battles, but the nationwide war, then we must open our eyes and understand.
MOWS could not do the work that it does without the regular financial support of both councils, TECT, BayTrust and Trevelyan's as well as other funders.
But we also could not do it without the support of the local and wider community.
Thank you to everyone, every little bit helps, but stay with us, it is a long, winding, but very worthwhile journey that we are on.