Survey of the 1997-2000 Kaipatiki Creek Restoration site, April-June 2019

The Initial Survey for this Project is of the 1997-2000 Kaipatiki Creek Restoration site, ie streambed, banks and adjacent forest to borders of private land where possible.

It follows a series of explorations from June-December 2018 of those areas of the site handweeded from 1997-99, starting at the entry to Witheford Reserve's Native Plant Trail
https://inaturalist.nz/observations/23020882
https://inaturalist.nz/observations/17549721

The Survey is to be ongoing and supplemented with specialist input as available.

The following areas, though of great interest, we will not be able to be include in this survey:

• Cliff faces and steep slopes
• Manawa beds and other saltmarsh communities except as seen from the shore (though we will provide links to some of the observations from a survey by the 1997-99 volunteer group and a botanist)
• Areas hidden by dense undergrowth or fallen trees
• Forest margins bordered by housing below Witheford Drive (these could not be fully surveyed in 1997-99 either, due to the height and steepness of the banks and uncertainty about property boundaries)

The site's nature and history is described here:
https://inaturalist.nz/posts/23979-kaipatiki-creek-restoration-site

Some areas observed and hand-weeded in 1997-99 are now inaccessible to us, their steep contours hidden in dense wild native regeneration with the added uncertain stability of magnificent old rotting trunks fallen at all angles, along, down and across banks and the stream itself. We are studying archive photos to see which trees match the fallen ones. Many will be pines and wattles, but there were some kowhai 30-40cmD on the bank edge that had begun to tilt in 1999. Trees all along the streamside generally lean towards the stream, and many eventually fall into it. Presumably this is to reach light, but is perhaps also related to soil moisture or density? General info on this would be appreciated.

The kowhai on the coastal cliffs were a feature of this area in 1997-99, both above the estuary
https://inaturalist.nz/observations/13216768
and at the highest point in the forest of Witheford Reserve, just below private land which now holds housing:
https://inaturalist.nz/observations/13216741

At least some of the large old kowhai observed 1997-99 are still standing, their tall strong trunks part of the forest canopy
https://inaturalist.nz/observations/17734723
https://inaturalist.nz/observations/17345280
https://inaturalist.nz/observations/17630282

and piercing pohutukawa canopy on the coastal cliffs, the extent of their presence visible only in Spring with portions of canopy yellow with their flowers.

https://inaturalist.nz/observations/15410633

The native coastal kowhai seedlings are still abundant in the forest margins and on estuarine banks, ie alongside the soft-surface bush path created after road construction in 1999 through the Kaipatiki Esplanade Reserve
https://inaturalist.nz/observations?place_id=131524&project_id=kaipatiki-creek-restoration-assessment-2018-20&q=seedling&subview=grid&taxon_id=406092

We are also looking for successful maturations of the kowhai juveniles and seedlings of 20 years ago. Despite the abundance of kowhai seedlings, juveniles were never common, and mostly in the outer margins.

The site's pioneer species, eg ponga, mamaku, wheki, ti kouka, mahoe and kanuka, have matured and increased immensely, and are now interwoven with a replication of the streamside understorey of kiekie, karamu, kanono, hangehange, mapou, Parsonsia heterophylla, kiokio and huruhuruwhenua, along with many juveniles of the pioneer species, and huge mature Parsonsia, kohia and karaeo.
https://inaturalist.nz/observations/17945901

Tradescantia is now the dominant ground cover in many areas previously in kikuyu or other exotic grasses and weeds,
https://inaturalist.nz/observations/23772451

and has returned to some banks from which it was handweeded in 1998
https://inaturalist.nz/observations/18151257

At the streamside, Tradescantia now occupies some banks
https://inaturalist.nz/observations/18149485
that during the restoration project were treeless, exposed to sun and weeds, covered in kikuyu with only scattered Carex geminata and ferns.
(the same bank before restoration)
https://inaturalist.nz/observations/24173518

When restoration began in 1997, the dense, lush streamside vegetation dominating the streamsides today was seen only in places, mainly on the Witheford Drive side of the stream edge, and those patches of native vegetation were separated by wide areas of weeds, though kikuyu-covered areas were much more extensive on the Kaipatiki Rd streambanks, probably cleared and in some cases steepened in road construction
https://inaturalist.nz/observations/23045444

Much of that road edge is today canopied by the 1999 planted natives supplemented, though not greatly diversified yet, by wild regeneration
https://inaturalist.nz/observations/22597842

On the Kaipatiki Rd side of the stream, those vast banks of kikuyu hosted scattered blackberry, ginger, montbretia, pampas, woolly nightshade, wattles, pines, and some Tree privet, along with the Elaeagnus regrowth and numerous dead Elaeagnus and pampas that followed a 3-man, 3 week chemical control operation in 1997 in the upstream area, just before the volunteer manual restoration began.

In the downstream area, banks and retaining walls were created or raised during 1999 road construction, to speed up the progress of road traffic by creating a wide, straight, level road. This has made it difficult or impossible to closely examine the stream and its banks in places.

And on visits to date, mud has been too deep to access the saltmarsh and expolore the bottom of the cliff where 1997-98 surveys found a young Muehlenbeckia complexa. At the top of the cliff, we are keeping an eye out for Clematis forsteri, observed in 1997 both as adult and as seedlings on the cliff, and as seedlings in the streamside forest.

We have been surveying through telephoto lens the canopy of the streamside and opposite bank from the Kaipatiki Roadside forest margin, which also allows glimpses of the streamside vegetation in places between dense understorey, and the streamside where accessible. A few isolated large tree privet, wattle and woolly nightshade, extensive longstanding invasions of Elaeagnus, blackberry, and honeysuckle, and several metres of streamside Palm grass (Setaria palmifolia) have been identified in this way, none of them visible from the lower banks or paths due to the surrounding canopy and understorey, but later confirmed from the streamside as we gradually established their location and found safe passage through deep tradescantia among fallen trees and mamaku fronds along the crumbling and underhung banks.

Pink jasmine was solely responsible for the loss of almost all other vegetation of c. 20m of otherwise gorgeously fern-clad and forested streambank over about 40 years before its total release in the 1997 manual restoration
https://inaturalist.nz/posts/24833-pink-jasmine-in-kaipatiki-creek

The most obvious change to the whole site is the general absence of kikuyu , brush wattle and pampas, replaced by young native trees along the entire length of the roadside.

The native planting has been invaded particularly by tree privet, Moth plant and Japanese honeysuckle.
Honeysuckle, German ivy, moth plant and Madeira vine have already killed some trees, and threaten the remainder.

The unplanted mid-level of the steep banks, between wild regeneration along the streamside below, and the densely planted native trees at the roadside above, are no longer covered in kikuyu but in Tradescantia. The wild regeneration has progressed up the bank in some places at least, to be assessed in more detail for by reference to archive photos.

Less-accessible and less-visible parts of these streambanks host some large single-species invasions, eg approx 10 x 5m of dense Elaeagnus on the roadside bank above part of the stream known during the restoraton project as "Elaeagnus Block" (Zone Ea/Eb) , where in 1998-99 bushes 1-2mH on both banks prevented wading of the stream or walking its banks.

https://inaturalist.nz/posts/24180-elaeagnus-at-kaipatiki-creek

The single Madeira vine observed at the roadside in June 2018 has subsequently not been located, perhaps fallen down the bank towards the stream in the collapse of the tree it was strangling.

In April Madeira was observed flowering throughout the leafless upper branches of a Tanekaha about 10-20mH. Sadly, the Tanekaha is itself fruiting, but most of its upper branches are leafless or dead. Since the Madeira has climbed all the way to its very top, it seems likely the Tanekaha is being strangled, along with adjacent trees which we have not yet been able to view.

https://inaturalist.nz/posts/23717-madeira-vine

Madeira vine has since been observed, again distantly, on the downhill side of this group of trees, from the opposite streambank. Two tanekaha are among the trees on the outer edge of this canopy, and they appear to have at least some healthy branches. The tops could not be seen clearly enough to determine if either is the one viewed earlier from the roadside with Madeira smothering its dying top.

Since witnessing about fifteen years ago the fairly sudden death of a young tanekaha near the start of the Native Plant Trail, we have been keen to learn the cause, and the survival and health of the whole tanekaha population observed on the site 1997-99.

• https://inaturalist.nz/posts/23752-tanekaha-along-the-kaipatiki-creek-in-glenfield

There are several dead and dying beside the path near the upstream entry, while the older one at Rimu Pool further downstream looked vigorous and healthy in winter 2019.

Research at Auckland University suggests tanekaha might be affected by the kauri dieback pathogen. Since the affected tanekaha here are close to a public path, we requested assessment via Auckland Council Call Centre, and expect to be contacted by Biosecurity.

There has been ongoing growth of some Kahili ginger invasions not reached in 1997-99, and many new invasions.

A striking new observation during this Initial Survey has been Phoenix palm seedlings and a possible juvenile, 1 Chusan juvenile and 1 adult, and at least 3 Bangalow palms (Archontophoenix cunninghamii) c.5mH, ID confirmed on iNaturalist.nz by a Palm specialist botanist.

Two Bangalow seedlings have been found on the stream's edge near the upstream footbridge, in Zone Bd, and beside the path to Valecrest Place, just above the footbridge, and about 20 on both sides of the stream around the lower footbridge at Fernlea Rise. All were uprooted during observation.

More background and links to observations of the exotic palms can be found here: https://inaturalist.nz/posts/24179-exotic-palms-at-kaipatiki-creek

Another new threat is Yucca, several specimens of which are well established and inaccessible on steep banks.

• https://inaturalist.nz/observations/17119468
  Some seedlings collected frm the streamside in Sept 2018 were provisionally identified as Yucca, entirely uprooted, and are being grown on in pots to confirm their ID and record their appearance during development.

Yucca invasions of Kaipatiki Creek:
https://inaturalist.nz/posts/24846-yuccas-a-21st-century-invasion-of-kaipatiki-creek

Several Tree privet 10mH or more have been observed on the streambank, providing the only canopy at those points. Surprisingly, few juveniles or seedlings have been observed in their vicinity, perhaps limited by shade and Tradescantia. However, those seedlings that do survive, if not controlled, are sufficiently numerous and fast-growing to either create a lot work and environmental disturbance in controlling them as juveniles in a few years, or to replace native trees

Tree privet is now common both under light canopy on the stream banks and in the roadside margin, and without some ad hoc intervention in late 2018 many specimens would have overtopped native trees along the roadside planting's canopy margin. Juvenile tree privet is among the target species of the annual weed control operation to be done by Wildlands shortly in Witheford Reserve, and in progress in the Kaipatiki Esplanade Reserve.

Dozens of Tree privet at 1.5-5 cm spacings on the Coastal Cliff edge near the point have recently been felled. Probably hundreds more on the cliff face itself are not accessible to contractors. In this unusual occurrence, it will be interesting to see how those untreated thin themselves - will some die? Or will they all remain stunted together?
https://inaturalist.nz/observations/17886015
https://inaturalist.nz/observations/17886013

Locally rare species

Tawa
We learned from Wildlands 2017 survey that Tawa is present. As yet we have only observed a few possibly-planted juveniles. Unfamiliar with the species, we would love to be told where to look. It may be that they are not on the site here surveyed, but on the coastal cliff on the Bayview side of thecEsplanadd Reserve.

Kotukutuku
Kotukutuku is represented on the site by 2 adults and several juveniles.
Kotukutuku #1 was recognised in 1998, in better health than now. It was almost leafless in June and August 2018. We note that it is deciduous in southern areas, but this tree has lost limbs and grown smaller, not larger.

UPDATE August 2019 - This tree has been further revealed under a dense deep coverage by tradescantia. It is in fact now a larger tree, but ,amy of its leading trunks are growing horizontally, trailing down the banks to the water, over which their "top" foliage hangs.

So its health and vigour may be influenced by age?

Kotukutuku #2 was noted for the first time in May 2019 while watching raw sewage flow jnto the stream during rain. It hangs semi-collapsed from a storwater channel that developed jn 1998 in the collapse of the ground above. The channel becomes a powerful waterfall after heavy rain,carrying with it the overflow from a sewage manhole.
Kotukutuku #2, like #1, is almost leafless.

We will be following the progress of both, as well as any surviving juveniles along the Native Plant Trail:
https://inaturalist.nz/posts/23981-kotukutuku-native-tree-fuchsia-at-kaipatiki-creek

Native herbs, shrubs and groundcovers along the pathsides are discussed here
https://inaturalist.nz/projects/auckland-renh-project-kaipatiki-creek-methodology-trial-of-manual-weed-control/journal/24949-wild-native-pathside-vegetation

We are also re-surveying those areas of interest in our survey of June-September 2018, eg:

• the fate of the Gahnia, Dianella nigra and Carex spp that previously lined the path edge in the H Zone - did they get shaded out? We have yet to re-locate the exact 10m stretch of pathedge they spontaneously revegetated after wattle felling left the area sunlit.
• a number of fern species observed in 1997-99 and not yet seen 2018-19

-Puawhananga, both Clematis forsteri and C. paniculata, present in 1997-99 and common as seedlings in the older forest of the hillside gully

• the long-standing kanono-dieback syndrome now known to be caused by unknown environmental factors
• blackened dead native Basket grass (Oplismenus hirtellus spp imbecillus), beside the bush path
• any increase in the June 2018 observed Alligator weed in the estuary- is salinity controlling it?
• Japanese honeysuckle, wild rose and bougainvillea invasion of estuarine bank above saltmarsh, with honeysuckle reaching the manawa - how many/what species of trees now threatened by the honeysuckle, which is likely to have spread much faster than the others

-new developments and spread of seedling and juvenile native plants, cf the already-observed spread and development of Aruhe, kohia and Parsonsia

• what vegetation emerged and survived in areas of the 1998-99 felling of dense groups of wattles, and of a few individual Monterey pines.
• the recently-observed aggressive reproduction of several Hoheria, presumed planted, on the forest margin in and near the estuarine area
• any occurrence of Sophora microphylla seedlings. This species is not native to the area but was planted along the roadside post-road construction. If reproducing, it will be competing with the abundant wild seedlings in this area of the locally native S. chathamica

To be continued...

Posted on May 16, 2019 11:51 PM by kaipatiki_naturewatch