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Christchurch’s Port Hills are slopes of the extinct Lyttelton volcano, which last erupted around 6 million years ago¹. They are now covered with a mixture of grassland, forest, and rocky outcrops.

On one recent trip we investigated a small area within one of the most frequently visited parks; Victoria Park. We found a small gully, with rocky outcrops on either side. Within a distance of about 20 m we observed:

Tiger beetles (Cicindela sp.). We saw 3 of these - apparently they are 'gregarious'.

Flies. This one stayed still a little longer than most.

An orbweb spider

A moth, somewhat camouflaged amongst the rocks and lichen

Unidentified insects - larvae of some kind?

The rock itself ranged from fine-grained, to quite ‘holey’, to coarse-grained. Its colour ranged through brown/grey/black/white/pink.

Overview of the bluff, showing (mainly) fine grained rock

Cooled lava, that had lots of gas within it at the time of eruption

Cooled lava with phenocrysts within it

The rock faces also provide habitat for lichens.

Lichen covering rock

Lichens, with threads of spiderweb.

There was a lot to see, even within a very small area. We plan to return again, and soon.

(If anyone can help with identifying the little busy insects, we would love to know.)

For any other locals, the books we found especially useful were:

  • ¹Extinct volcanoes: A guide to the geology of Banks Peninsula. by Stephen Weaver, Rod Sewell, Chris Dorsey
  • Which New Zealand insect? by Andrew Crowe
  • Which New Zealand spider? by Andrew Crowe

Flickr Photos

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