Rotorua and environs, part 3

This is the final account of my perambulations around Rotorua, escorted by my host, local artist Geoffrey Cox. I will probably making some naming errors, so do correct me if you find any (politely, please!).

One day we took a short “tramp” around Lake Okataina. It’s completely surrounded by native forest, though introduced tammar wallabies are said to inhabit the area.  The lake is quite secluded but we came across one couple who had kayaked to a small beach:

I have come to love tree ferns, though it didn’t take much prodding. They’re gorgeous, and though they’re found in New Zealand, Australia, and South Africa, they’ll always remind me of New Zealand.

The forest around the lake comprises nearly all native plants:

Fungus on a dead tree:

Another fungus that eerily resembled (and felt like) human ears. I don’t know any of these species; perhaps a reader does.

This fungus was growing by a cut-down tree beside Lake Rotorua–in town:

A big piece of moss-covered obsidian we found on the trail. This volcanic glass is very hard and takes a sharp edge; it was much prized by the Maori for their tools and weapons.

Below is Lake Tarawera, one of the several lakes near Rotorua. Here’s a bit about it from Wikipedia; be sure to read about the now-vanished Pink and White Terraces:

The lake was substantially affected by the eruption of Mount Tarawera on 10 June 1886. The eruption killed over 150 people, and buried the Māori village of Te Wairoa on the southwest shore of the lake.

Also destroyed were the famed Pink and White Terraces.

Three adjacent volcanoes whose eruption has greatly altered the area around Rotorua over the centuries. I believe their names are Ruapehu, Tongariro, and Ngarahoe, but I may be wrong.

Below is an unusual specimen of the native lancewood (Pseudopanax crassifolius). I’ve written about it before as a possible vestigial remnant of moa browsing, but I’ll give the bit from Wikipedia:

The juvenile form, which lasts for between 15 and 20 years, is very easily recognized. The leaves are stiff and leathery with a prominent central rib, about 1 cm wide and up to 1 m long with irregular teeth, all growing downwards from a central stem. The young trunk has characteristic vertical swollen ridges. As the tree gets older the stem begins to branch producing a bushy top, and the leaves become wider and shorter, losing their teeth. It is only when the tree is mature that it adopts a typical tree shape.

Usually the lancewood sheds all its juvenile, moa-adapted foliage when it gets bigger, but this big tree sprouted a single twig at the bottom that had the juvenile foliage, which is tough and serrated:

The crown of the same tree:

A few local fowl. This is the Australasian moorhen, or pukeko (Porphyrio melanotus), also found in New Guinea, Australia, and Indonesia. It’s a handsome bird, and pretty common.

Black swans (Cygnus atratus) are also found in Australia, where they were probably native, and were likely brought to New Zealand in the 19th century. This is a nesting pair by a lake.

The Little Shag, or Little Pied Cormorant, also called kawaupaka (Microcarbo melanoleucos), is an Australasian bird.

Now an endemic species. The New Zealand grebe, or dabchick, bears the Maori name of weweia and the Latin binomial of Poliocephalus rufopectus. It went extinct on the South Island but can still be seen, with difficulty, on the North Island, as they’re shy, uncommon, and dive deep and swim far underwater. They’re hard to spot as they also swim low in the water. This is the best I could do, but I’ve put someone else’s photo below:

The grebe (from New Zealand Birds Online):

Finally, about 15 km from Rotorua there are hundreds of these mounds scattered throughout the flat fields, often topped with a boulder or rocks. Geoffrey had no idea how they were formed (not of human origin!), so any solution would be appreciated.

Black swans in a beautiful spring-fed river near Rotorua:

A reflection of tree ferns in the spring:

Finally, the obligatory self-portrait—this on the screen display of a security camera in a Rotorua bank:

34 Comments

  1. DrBrydon
    Posted April 9, 2017 at 10:12 am | Permalink

    That second mound picture looks like a grassy painted desert, so I am going to say erosion.

    • Frank Bath
      Posted April 9, 2017 at 11:31 am | Permalink

      Might they be volcanic plugs?

      • gormenghastly
        Posted April 9, 2017 at 12:45 pm | Permalink

        That would be my theory. They’re very common between Taupo and the Bay of Plenty (Rotorua is in the middle of that region)

    • Mark Sturtevant
      Posted April 9, 2017 at 1:14 pm | Permalink

      I thought so too. Rocky outcrops that resist erosion while being covered in vegetation.

    • Heather Hastie
      Posted April 9, 2017 at 1:22 pm | Permalink

      There were multiple huge (house size and even bigger) rocks ejected when Taupo erupted, creating the crater lake we see today. Some of the rocks landed as far away as Taumarunui and Pio Pio to the east. (The Pio Pio ones featured in LOTR.)

      I wonder if there are rocks under those mounds and dirt etc has built up around them since, or they were initially also covered in ash (they’re much closer to Taupo than Taumarunui etc.) then other stuff has built up. Iirc, the Taupo eruption was at least 650,000 years ago so there’s been time.

    • Stuartg
      Posted April 10, 2017 at 2:37 am | Permalink

      Lake Rotorua is in a volcanic collapse caldera, as is Lake Taupo.

      Surrounding both of the calderas are massive areas subjected to pyroclastic flows during the eruption phases.

      I wonder if pyroclastic flows have contributed to the appearance of the landscape? I’ve driven past them many times and always wondered about it. Never seemed to find the right geological texts to give me the information, though.

      • infiniteimprobabilit
        Posted April 10, 2017 at 3:32 am | Permalink

        There’s a medium-scale (1:250,000) geological map accessible at
        http://data.gns.cri.nz/geology/

        Don’t know if it helps, I’m not sufficiently familiar with geological maps to read it properly.

        cr

        • gravelinspector-Aidan
          Posted April 10, 2017 at 5:32 pm | Permalink

          Reading that map around the Lake Rotorura is mostly mapped in the pale lilac as “Middle Quaternary ignimbrite” (I’ll describe the rock types down-message, once I’ve collated the data) ; deeper lilac “Middle Quaternary rhyolite” ; yellowish “Late Quaternary lake deposits” ; grey “Late Quaternary ignimbrite” ; white “Late Quaternary alluvium and colluvium”.
          (If you click on a feature on the map, a popup appears with the description of the entity drawn – a boundary, a rock unit, elsewhere perhaps faults.)
          “Quaternary” – a time period of the recent (2.58 Ma) to present (neglecting the current debate over the validity and definition of the “Anthropocene”). Exactly what they mean by Middle and Late would require more metaphorical digging. Quaternary sediments are typically poorly consolidated rock, easily moved by wind, rain and rivers.
          “Alluvium” – river deposit muck. Colluvium is the same sort of muck, creeping down hillsides but which hasn’t been shuffled by rivers, yet.
          “Ignimbrite” – lovely things, you don’t want to watch ignimbrites being deposited except through a good telescope. If you take a gas-rich lava and throw it off the top of a mountain, enough gas can be released (and air entrained and heated by the lava) to make the gas-lava-air mix into a low viscosity fluid flowing down the volcano flank at hundreds of km/hr and hundreds of degrees centigrade. If you know your volcanic history, I’ll just say “Mont Pelee and St Pierre” ; otherwise, I’ll say 30,000 dead in minutes or less.Being somewhere else is a really good idea.
          To the original point : the area is certainly mapped as blanketed with pyroclastic flows. Exactly what has been going on … this page has a rather worrying phrase : “single event caldera”. Do some back-of-a-thumbnail calculations on the volume of the visible hole and the words “single event” and you’ll get “I didn’t want to be anywhere nearby” as the answer. Odds on the order of 240k : 1 against a repeat in any random year are less discouraging (the comparable figure for the million odd casualties-to-be in Naples is more like 2k : 1). But I’d still keep an eye on press reports of thermal springs doing weird stuff, if planning a trip. The seismology drum looks really boring, and in this context, boring is good.

          Hunting for a bit more info, I find this thesis document which has all sorts of horrible words like “145m thick” and “boundaries between ignimbrite units are gradational”. This sounds like a good place to have not been, one fine morning about 1/4 million years ago. And I really must bump the Naples area and Rome up in the “should visit” lists.

          • infiniteimprobabilit
            Posted April 10, 2017 at 8:23 pm | Permalink

            I wondered if the Gravelinspector would notice!

            Mont Pelee is kinda famous.

            But the Taupo eruption was in a whole different class. The volcanic equivalent of ‘going nuclear’, or a Magnitude 9 earthquake.

            If it ever went again, it would not be safe to be anywhere near it, ‘near it’ in this instance meaning almost anywhere in New Zealand…

            By the way, I suspect Taupo may be the reason large parts of the North Island hill country are built of very low-grade ‘rock’ – that is, soft mudstone, which erodes easily into steep gorges and when disturbed and wet just crumbles into mud. Hence the very large number of ‘slips’ on the roads in wet weather.

            cr

            • Stuartg
              Posted April 11, 2017 at 2:34 am | Permalink

              Regarding the Taupo eruption. From memory, ash deposits from the Oruanui eruption are 8-20 cm thick on the Chatham Islands, about 850 km away.

              That was a seriously big eruption. I suspect the safest place from which it was observable would have been the surface of the moon!

            • gravelinspector-Aidan
              Posted April 12, 2017 at 2:18 pm | Permalink

              By the way, I suspect Taupo may be the reason large parts of the North Island hill country are built of very low-grade ‘rock’

              It’s a good possibility. I’m not at all familiar with the area, but the eruption would definitely have been one of the worse of bad hair days.

  2. Diana MacPherson
    Posted April 9, 2017 at 10:13 am | Permalink

    I saw lots of those mounds too in a small town in NZ’s north island. There were shells in them and friends said that the Maori used to eat shellfish up there.

    Love the pukeko! I love those birds!

    • Robert Seidel
      Posted April 9, 2017 at 12:00 pm | Permalink

      Fossil shells, right? In that case I’m gonna say, ancient reef patches.

      • Diana MacPherson
        Posted April 9, 2017 at 5:08 pm | Permalink

        Nah, just regular shells.

  3. infiniteimprobabilit
    Posted April 9, 2017 at 10:58 am | Permalink

    Errm, wrong mountains.

    The three adjacent volcanoes Ruapehu, Ngauruhoe and Tongariro are in Tongariro National Park south of Lake Taupo, Ruapehu being the highest in North Island (something over 9000 feet).

    The mountain in your photo is Tarawera (seen across Lake Tarawera) southeast of Rotorua, a flattish dome with a huge split (crater) down the middle, whose eruption buried Te Wairoa village and the pink and white terraces as noted. It’s just 1111m (3600 feet) high, though it was probably more before it blew its top off.

    cr

    • infiniteimprobabilit
      Posted April 9, 2017 at 11:57 pm | Permalink

      By the way, for checking out photos, I find Google Maps + Streetview extremely useful. I’ve reconstructed my (lost) wanderings through English country lanes and French mountain tracks by comparing my snaps with Streetview.

      Also, http://www.topomap.co.nz/NZTopoMap has the 1:50,000 LINZ maps of the whole country in clickable zoomable form.

      cr

  4. rickflick
    Posted April 9, 2017 at 11:51 am | Permalink

    I’d guess that the mounds are small volcanic cones. That would mean there should be evidence of either magma flow or layers of loess.
    That’s a charming selfie. I’m puzzled by the panel under the feet of both of the bank tellers. Could it be a trap door? If the place is robbed the tellers exit the scene by hitting a button that drops them out of harm’s way. Or not.

    • Derek Freybegr
      Posted April 9, 2017 at 11:58 am | Permalink

      More likely some of those mats that are used in commercial kitchens and other places where people have to stand a lot. The kitchen ones are porous, bank ones wouldn’t have to be.
      With no handguns in NZ, bank robberies are rare.

    • Posted April 9, 2017 at 12:33 pm | Permalink

      That is an interesting take on the panels under the tellers but it is sadly a little more mundane than that. They are rubber mats usually a little spongy for comfort when standing at a counter for long periods…but I suspect you new that….

    • gormenghastly
      Posted April 9, 2017 at 12:47 pm | Permalink

      They’re slightly spongy for comfort, but also reduce the static electricity you’d get from shuffling about on carpet while working.

    • rickflick
      Posted April 9, 2017 at 5:04 pm | Permalink

      Spongy is not as exciting as trap doors, but I’m sure spongy is correct. 😎

  5. Posted April 9, 2017 at 12:15 pm | Permalink

    Wow, bank tellers out in the open with customers. Don’t people rob banks in New Zealand?

    • Heather Hastie
      Posted April 9, 2017 at 1:30 pm | Permalink

      Those ones are information people. The ones who hand out money are better protected. But as Derek Freyberg says in the comment above, bank robberies are rare here. There are almost no handguns.

      Yes, Second Amendment supporters, I’m afraid it’s true: having no handguns really does make life safer and more pleasant.

      • Posted April 9, 2017 at 2:22 pm | Permalink

        Typical NZ bank robbery: A man with a parrot on his shoulder walks into a bank and says “Gimme the money or I’ll sic my kea on you.”

        • Heather Hastie
          Posted April 9, 2017 at 2:47 pm | Permalink

          He’d be arrested for mistreating a native bird, though actually the kea would probably enjoy it immensely! 😀

        • gravelinspector-Aidan
          Posted April 10, 2017 at 5:36 pm | Permalink

          Sadly, too many of the Monty Python team have shuffled off (etc etc)

    • Kiwi Dave
      Posted April 9, 2017 at 9:00 pm | Permalink

      ‘Don’t people rob banks in New Zealand?’

      This is the Antipodes. When I look at the interest rate for my term deposit, I think it’s the other way round.

  6. tubby
    Posted April 9, 2017 at 12:39 pm | Permalink

    Those ear-like mushrooms may be Jew’s ears, Auricularia auricula-judae. Wikipedia reports them to be edible but not sought after, and must be cooked.

    • Phil Garnock-Jones
      Posted April 10, 2017 at 6:03 am | Permalink

      Yes, and the orange one above it is an introduced fungus called Favolaschia calocera, orange pore fungus. It has become very common.

  7. Jiten
    Posted April 9, 2017 at 12:59 pm | Permalink

    The photo of the reflection of tree ferns in a spring is beautiful. It’s like an impressionist watercolour.

  8. Mark R.
    Posted April 9, 2017 at 1:17 pm | Permalink

    The legs on that pukeko are amazing…like a miniature moa.

    Truly beautiful setting…the black swan photo looks to be taken right out of a fairy tale.

    • infiniteimprobabilit
      Posted April 9, 2017 at 11:40 pm | Permalink

      I missed the pic of the pook.

      They’re one native species that has taken civilisation in their stride. Motorway margins, any waste ground near water, you’ll find pooks. To my surprise, they can actually fly, though they rarely bother.

      They’re also said to be not good eating. Old bushmans recipe: Put the pook in a pot with a rock and boil until the rock starts to crumble. Then throw away the pook and eat the rock.

      cr


2 Trackbacks/Pingbacks

  1. […] Source link […]

  2. […] via Rotorua and environs, part 3 — Why Evolution Is True […]

Post a Comment

Required fields are marked *
*
*

%d bloggers like this: