Wednesday, 7 May 2014

Fishing for giants

I made a huge mistake, and had a couple of days off. I was noticing myself getting a bit lazy when spidering, so decided to have a break and then return to fieldwork to reboot myself. Besides, writing tasks have crept up on me in their own special way and I needed to spend a bit of time addressing those.

The result was that I lost my mojo somewhat, and upon returning to fieldwork I couldn't find any spiders. The one population that I found was tiny, and I couldn't convince the spiders to come out. Makarora, Moana and the West Coast were all searched fruitlessly. Where were the giant spiders said to inhabit this part of New Zealand? Surely their size should make them obvious. I received calls and texts from local people, but unusually they were all misidentifications. I may need to add another line of description to my poster; if it's hanging off your wall, it's not a trapdoor spider. Nonetheless, I'm grateful for every call that I get; it shows my system works.

Heavy-hearted, I headed up to Takaka in Golden Bay. I had visited Golden Bay many times during my masters, and it's one of my least favourite parts of New Zealand (although the drive there is fabulous). I have no idea why it's such a hugely popular tourist destination. Once you get over Takaka Hill there is flat farmland for many kilometres, and then you get towns and typical flat sandy beaches and cultivation and urbanisation and everywhere......people. If you head north the tourists become fewer and the scenery marginally better. Pupu Springs is an incredible place to visit, with rushing streams and blue burbling cold water and fantails everywhere.

Pupu Springs and fantail

Then you get up to Farewell Spit, which is an area sparsely populated by creepy old guys.

I found spiders on Takaka Hill, right at the foot before you start climbing towards Golden Bay. The first lid that I saw made my heart jump, and I thought that it could not be a Cantuaria burrow. But I lifted it to reveal a smooth, silk-lined tunnel about 5 cm in diameter. Given that the last Cantuaria that I had caught were living in 5 mm diameter burrows, I was a bit shocked to find such large burrows here. Cantuaria always seem to squeeze themselves tightly into their burrows, so that you wonder how they fit; how big would these behemoths be?

I checked into the YHA backpackers and made some friends before heading out after dark to catch the spiders. Rain was pouring out of the sky in sheets; the washouts, landslides, wind and fog made driving rather unpleasant. I was a wee bit apprehensive about the lack of visibility, since the spider population was right at the side of the road next to a corner. My fluoro vest didn't seem quite adequate. Also, I have never been able to get spiders to come out in the rain yet. I hoped it would not be yet another fruitless spidering session.

Luckily the rain eased off into drizzle by the time I reached the population. I had marked 11 burrows and was happy to see that most were cracked open, with the occupants' feet just peeking out beneath the lid. As soon as I walked by, most snapped shut in an instant. A couple stayed open, so I dangled Pete the beetle in front of one of them until his back feet touched the ground next to the burrow. Usually, you have to wait at least a few minutes for the spider to react, but not this time: she erupted from the burrow and launched herself at him before he was fully on the ground. I flinched, unused to seeing such a large spider, but she was not as big as I had expected. Into the tube she went, and onto the next burrow-dweller.

This one did not have her feet at the entrance, but the lid was badly fitted to the burrow mouth and I could see through a crack into her burrow. She was not there. I put Pete a few centimetres away (ashamedly, I had not the heart to put my fingers so close to her burrow) and let him walk towards the lid. When he reached the spot just below the lid, I pulled back on the leash gently so that he had to grapple at the soil right outside the burrow's entrance. After a few minutes, nothing had happened. I began to think maybe she had recently died or vacated the burrow for some reason. I kept Pete there anyway, because sometimes spiders are right at the bottoms of their burrows when they first feel the beetle and they take a while to reach the top. I was beginning to think about moving onto the next burrow when my distracted eye caught a flicker of movement. I couldn't see anything, but focused intensely on the crack between the lid and the soil. A furry spider tarsus (foot) emerged slowly. Pete had piqued her interest, but she was not overly enthused. I twitched him to the left a little, but the foot disappeared. We played this game for some minutes, the spider creeping out of the darkness, but never quite enough for me to catch her. Then I put the tail end of Pete's leash next to him, and let go of it so that his crawling also tweaked the loose end. That was enough for her. She slid out like a shark's fin from the water, hardly disturbing the lid of her burrow at all. Usually a trapdoor spider catching a beetle is a dramatic, explosive event, but this one was much more graceful.

I collected her and walked along the rest of the burrows, trying them here and there to see if any would take the bait. Then I returned to the first, the five centimetre one, the biggest. Her feet were poking out, so I dropped Pete down.

I have no idea how she sensed him. Supposedly, trapdoor spiders do not have good eyesight, but they are very sensitive to vibration. Pete was still in the air when the lid of her burrow flipped back and she pounced on my beetle. I didn't even have time to move him out of the way, and her fangs went right through him and she hung with him at the end of the string. I nearly dropped it in shock, but was able to put it on the ground next to the road. The spider was upside down and still biting Pete. One fang pierced his wing case into his abdomen, and the other had sunk into his thorax behind his head. She was waggling her fangs about, possibly to drive them in further or perhaps she was also trying to show me some aggression. Her fangs were about 5 mm long, and so shiny that they looked wet. I put both her and Pete into a vial and drove back to the backpackers. I normally take five spiders from a population, but this one seemed quite small so three would have to do.

Spiders from Takaka Hill. The bottom one is lying on her lid. Photos by Billy from the backpackers.

I'm in Nelson now, and last night I caught three more spiders. Hopefully this means my luck has returned. I really need to find some males though...

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