Te Anau Glowworm Caves

It started raining overnight, and as I write (8pm) it hasn't once let up. And it's real rain, the sort I can only remember experiencing in Scotland! (A full-speed wipers job when driving). Never mind, the next 2-3 days sound better according to the weather forecast, so fingers crossed.

We haven't, however, let it cramp our style. This morning we went on a glowworm cave trip. This required a half-hour boat ride across Te Anau Lake to get to the caves, then a 5-10 minute subterranean walk. The main blip shows my Editor and our guide about to enter the cave; hobbits would find it easy as we had to crouch down to about 3 feet tall to get under the entrance stone.

Once we'd walked along a track in the cave we embarked on small barges and were then plunged into total darkness while the guide gently pushed the barge along a channel and into the glowworm cave itself. It was amazing to see all the tiny pinpoints of light (you have to take it on trust that they really are glowworms and not miniscule LED lights!). Where the worms were most concentrated you could just see your hand in front of you once your eyes had fully adjusted to the darkness.

Apparently the glowworms hate light and noise so sadly photographs are strictly forbidden in the cave. So the extra is a fiddle - it's a photo from the video screen in the visitor centre showing a glowworm larva.

I knew nothing about glowworms before. We were told that these ones aren't fireflies, as are some "glowworms", but larvae of the Fungus Gnat (Arachnocampa ). The larval stage is by far the longest part of the life cycle, lasting for about 9 months prior to the 12-14 day pupal stage and the 1-5 day adult stage, the sole purpose of which is to breed; once the eggs are laid they take 20-24 days to hatch and the cycle starts again.

At their largest the larvae reach about 3 cm long. It's their tail which glows, to attract cave insects which then get trapped on sticky strings of web-like "fishing lines" (up to 70 per larva) which they excrete. The worms then inject an enzyme to predigest their prey which they then consume like a milk-shake (yuk!).

This afternoon we drove (or, almost, "sailed"!!) to Queenstown where we're based for the next 2 nights - hoping for some sun tomorrow :-)