Jobs for Nature programme in Mangaiti has started

 

At 7am on Monday 4^th October, we welcomed the Jobs for Nature crew to their first day on the job. This has been a long drawn out process, with covid continually causing delays. The week before, DOC approved our covid management safety plan which gave us the all clear to finally get started.

There are three organisations that we must acknowledge and thank for their support, without which this project would never have got off the ground. Go Eco with their administration infrastructure to support the employment of staff, Ngāti Wairere whose Hapū covers the Mangaiti Gully and Hamilton City Council who are the legal guardians of the gully.

The full welcoming ceremony, which we originally planned, was skuttled by level 3 lock down. Notwithstanding covid, we are hopeful that we may be able to resurrect this in the near future and have a community open day, when the public would have an opportunity to meet the crew and discuss our future plans for the next three years.

The JFN Crew will be focusing their work in Zone 2 of the gully.

A survey of stream fauna - eDNA

 

Setting up a passive eDNA collection filter 

A new testing programme has been developed by Wilderlab in Wellington, to capture through filtering stream water, then reading the DNA captured within the filter, to identify the species present. This process is called environmental DNA or eDNA.

The Mangaiti Restoration Trust is one of over 200 community groups, hapū and kura who have signed up to the Environmental Protect Authority’s (EPA) programme Wai Tuwhera o te Taiao - Open Waters Aotearoa. The programme promotes the use of eDNA to discover what species live in their local lakes, streams and rivers and coastal waters. Local co-ordination is being carried out by advisors from NZ Landcare Trust.

From the initial one sample pack supplied by EPA, we have purchased another four with funding from HCC and donations. There is anecdotal evidence that the different arms of Mangaiti Stream have created their own habitat (and not always good), due to where the stream source comes from and the type of vegetation around and over the stream as it runs through Mangaiti.

This sampling is going to give us a basis to develop a stream management plan. We will know what to protect, where the different species are and the habitat that each indigenous species requires to thrive.

Woolly nightshade (an aggressive weed)

 

We have seen woolly nightshade being cultivated as a shrub, with people completely unaware that it is a noxious weed, that we are attempting to eradicate. It is an aggressive, rapidly growing shrub or small tree reaching up to 9 metres in height. Its oval leaves are large, grey-green and are covered with furry hairs. It has a strong unpleasant kerosene-like smell when the leaves are rubbed or crushed. Flowers are purple with yellow centres and grow in clusters at the ends of branches. Berries ripen to yellow and when broken open contain hundreds, if not thousands, of seeds which birds distribute.

When the bushes are small to medium in size, they are easily pulled out roots and all. Large plants can be cut off at the base and the stump poisoned (cut’n’pasted or painted with a bit of concentrated weed killer) otherwise they will regrow. 

Kowhai seed collection – Port Waikato

 

One of the challenges of collecting seed for a restoration area is to get a seed source that is not cross contaminated with other closely related species or hybrids. This is particularly difficult the closer you get to an urban area with many of the plants in domestic gardens purchased from commercial nurseries. This problem effects some plants more than others. Kowhai is one that is particularly vulnerable. The kowhai seed collected this year, was from a pocket of bush on a remote farm north of Port Waikato. Not only was it a very good tree specimen profusely flowering, but also had good nectar producing flowers evident by the number of tui feeding.

Blackbirds fighting

 

From time to time most of us would have seen male blackbirds having a bit of a scrap over their territorial boundaries. This scrap between two female birds on the attached video clip took scrapping to another level. The ferocity was surprising. You will note in the latter stages a male bird gets involved trying to break up the fighting. This video was captured on the path just along from the shade house down in Mangaiti gully.

Cabbage tree moth damage

 

I am sure many of you will have seen a cabbage tree with what appears to be a knotted growing tip. Gerard Kelly (HCC) thinks the top area where the cabbage tree is deformed, could be caused by cabbage tree moth larvae (Catamacta lotinana). The larvae mine the leaves and then migrate to the tips, weaving and knitting the tips together. They then eat leaves from inside out. Lower leaves showing characteristic caterpillar feeding, tips get quite frayed and could be easily spun together. If you see a cabbage tree like the one in the photo it would be worth investigating.

Tūī with brown plumage

 

A brown tūī was reported in Rototuna and has been frequenting a feeding station that backs on to Tauhara Park. Apparently, this is not all that uncommon as Neil Fitzpatrick from Landcare Research says that it’s pretty much identical to tūī that have been regularly seen around Whatawhata since at least 2006 when he photographed one. There were at least two individuals with that colour abnormality present at the same time, and they have been seen for such a long period that I think there have been several generations. Perhaps this one is related.

There are a few colour abnormalities similar to this (e.g., leucism, progressive greying,) but I think these tūī are all examples of the unimaginatively named “brown” mutation (defined as a qualitative reduction of eumelanin). In many birds this is more often seen in females, and all the tūī I have seen like this were female.

Aerial footage of zone 3

 

For those living on the Zone 3 section of the gully (up to Gordonton Road) will be well aware of the clearing in preparation for planting and track building that is going on. One resident, Jason Lee, has captured a valuable historic aerial view of this at it’s very early stage. One thing it does not show is how wet and boggy the gully floor is.

Here are links to two You Tube clips. They are basically the same just two different directions.

Gordonton Rd to Keswick Cres Path

https://youtu.be/mXte8HT1jvU

 

Keswick Cres Path to Gordonton Rd

https://youtu.be/C19AGK91s6I

Reports of large wētā

 

We have had two reports on the exceptionally large size of wētā seen in our gully of late. This will most likely be because they are growing larger (and living longer) without the rat predation that has been around previously. To be fair on rats (if you want to be fair on rats) they are not the only predator on wētā. Cats (yes, your moggy), hedgehogs and possums also give them a hard time.

Wētā have been around long enough to see dinosaurs come and go and to evolve into more than 100 different species, all of them endemic to New Zealand. They have become icons for invertebrate conservation in New Zealand because many species are threatened or endangered although not the tree species in our gully.  This does not mean we shouldn’t look after the environment that supports them though.

Wētā hotel / motel are popular and a lot of fun to have in trees in the gully behind your property if you are lucky enough to live on a gully edge. You can make your own (search on google) or you can buy one from Go Eco located in Frankton, Hamilton for around $30. 

pdf Library additions

 

We are currently having technical issues with the pdf Library link. We lost our hosting site as they no longer accept pdf files. The files are now sitting on google drive however this does not give instant access for those not registered. We are currently looking for an alternative. 

If you have accessed the pdf Library link in the past you may have to clear your browser cache to get into google drive.

Settings - clear browsing data - cache. 

Two documents have been added to the pdf Library

 The Planting Register by Species 2021 from this planting season and Step Building DOC specs on step building, depending on how steep the bank is, as to the type of steps that can be built. These specs are suitable for a surprisingly steep bank, but it does have it’s limits. The steeper the bank the narrower the tread. Once the bank gets too steep for this design you would have to look at floating steps where the tread is flat, and you step on the boards. If too steep for that you are looking at a ladder fixed to the bank and that is very steep!

Another tip on building the DOC specs steps, is make sure that after installing the first side plank that the second side plank is not going to be left floating with little or no ground under it.

Iron floc in streams is perfectly natural

 

Iron floc seeping from the stream bank

Floc is the fluffy material you see in some waterways, sometimes forming soft stalks. It is quite delicate and will break apart easily when disturbed so even though it may not be ‘aesthetically pleasing to the eye’ it is an important metabolic process that should be allowed to occur, and in fact is likely to be a very ancient process in the context of the development of life on earth (there is actually a good deal of research on different iron oxidizing bacteria, and it is a worldwide phenomenon). The harvested electrons by the bacteria provide energy for reproduction and other life-sustaining processes in the life of these single-celled organisms. A variety of species and sub-species of bacteria carry out this process. It requires oxygen, so these bacteria live and reproduce where iron-rich water flows out of the ground and is exposed to oxygen in the air. This is a completely natural process.

Interestingly enough, and it has not been worked out why, we find that giant kokopu are very fond of streams that have lots of iron floc, with good populations in some urban and perimeter urban Hamilton streams.

In this You Tube clip https://youtu.be/8w0kgAwv1Ps taken in the Gordonton arm (zone 3) of Mangaiti Gully stream you will see the iron floc floating about from the disturbance of the eels. A giant kokopu is visible at the end of the clip. Kōura / freshwater crayfish have been found a little downstream from this photo point. All indicating healthy stream fauna happily living among the iron floc.

Fishing prohibited signs to protect longfin eel / tuna

Several people that live on the gully feed eels in the stream below their properties. There are two types of eel: the shortfin, which is more common, and the longfin which has a DOC classification of “at risk – declining”. Eels have been written about before on this blog site. They have a remarkably interesting life cycle. The longfin grows up in the streams for 30 to 60 years, after which they leave the stream systems and migrate out to sea, swimming up to the tropics (around Tonga) to mate, spawn then die. The little glass eels drift back to NZ and find a stream to migrate up and so the cycle continues, unless someone fishes them out of the stream, often for no other reason than for “fun” leaving them to die on the stream bank.

Part of council’s project to develop the Gordonton arm (zone 3) is to cut a track to give access. Unfortunately, this also gave access to the public, and we have received a number of reports from concerned neighbours that fishing was going on and they feared for their “pet” eels. Once it was brought to council’s attention, signs were made and placed along the stream length.  

Unfortunately trying to protect our native fauna seems to be an ongoing battle.

Rat trapping trial

We have run a highly successful rat control community-based programme for the last ten years. This programme uses a bait block containing bromadiolone as an active ingredient. The design of these blocks was to have a very low, to no, secondary kill. In other words, if something ate a dead or dying poisoned rat it would not also be poisoned. We felt this was important because of domestic cats and dogs in the area. When you have a programme like this it is important that you have the majority of people in the area on your side and we would not get that if we were knocking off their cats and dogs. Incidentally, some baits, brodifacoum for example, are designed to have a secondary kill. This bait, which goes under a number of proprietary names, is freely available at most hardware stores.

Successive programmes around the country which have tried to get a good knock down of rat numbers using only traps, have never been successful. Remember it is not how many rats you catch, but the number of rats left. Rats are prolific breeders with one pair in spring potentially responsible for up to 2000 offspring by late autumn. Therefore, our aim has been to eradicate all resident / breeding rats and then knock out reinvasion to prevent the rats getting re-established. To date we believe we have been successful.  

So why look at traps? The use of toxins has never been ideal.

There are two motivations for this trial. One is that ruru / morepork owls nest in the gully. They catch mice. Mice also feed on the poison baits. Although the bait should have a low secondary kill, we do not know what effect it would have on chicks. Secondly Hamilton City Council has always been uncomfortable with our community-based programme.

Owl with mouse at nest in Mangaiti Gully 

Koi Carp not a problem in Mangaiti Streams

 

Koi carp are a very invasive and ecosystem destructive species so when a report was received of a sighting in the stream on the western side of Hukanui Road it was a concern that potentially, there was another invasive species that we had to contend with. Fortunately, this was found not to be the case after discussing the matter with Bruno David: SCIENTIST- water, science, and strategy, at Waikato Regional Council.

He said that while the odd koi carp may appear and may even move up into the wider system, the broader catchment is not an ideal habitat for koi to do well in (other than maybe the very lower reaches near the confluence with the Waikato River mainstem). Koi carp much prefer slower flowing, warmer water to cruise around and fossick among soft substrate (mud) etc. Koi carp only become a problem (and create measurable water quality changes) in systems when they get into densities that are >80-100kg/ha and he would be extremely surprised if this ever occurred up the Mangaiti. The odd fish, therefore, would be very benign.

Carp have been around in the lower Waikato system since the late 60’s and they are very dispersive so in most cases they have already infiltrated the places that they can reliably get to and want to get to. The fact that we do not see them routinely in the Mangaiti, indicates that they do not really want to go up there as they have much better options elsewhere.

So, all round it sounds as if we are safe from this pest species. On saying that if you do see one feel free to remove it from the stream notwithstanding the “Fishing Prohibited” signs around.

Nikau planting

14-year-old palms in 45Lt pots 

Nikau are very slow growers. It takes a good 15 years for them to form the beginnings of a trunk, so a two-metre specimen may be more than 30 years old. Our native nikau are prolific berry producers that are favoured by kereru / wood pigeon. Not only do kereru gorge themselves on the berries but they are very effective at seed dispersal, so once nikau are established and fruiting the cycle of distribution begins and they become self-sustaining.

Because of the long establishment time, we purchased twenty 14-year-old palms in 45Lt pots for this season’s planting. These have been planted in groves of five, in four different locations around the gully to supplement smaller nikau that have been planted over the years.