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July 8, 2016
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July 8, 2016
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Female Spider Catching Wasp Traps Her Victim

Upon leaving Gondwana Lodge for an afternoon safari with my new guests, we were filled with excitement and adventure as everyday at Sanbona Wildlife Reserve has its own surprises to offer. We were barely out the gate and into the wild when I saw an unusual movement on the road in front of us. We stopped beside the sighting and were absolutely blown away by what we saw.It was a female spider catching wasp dragging her paralyzed victim (a baboon spider) across the road.

The moment we stopped next to her she got a bit paranoid and flew off. She did a bit of a circle then came back. By then we had moved off a bit to give her some space. It was rather amusing to discover that she was using us as a marker. Most of the higher Hymenoptera (sawflies, bees, wasps and ants) have a remarkable memory and sense of direction. She came back and hovered in the same spot opposite my door only to find no spider. I had to reverse back to the spider in order for her to find her victim.

Large metallic blue/black spider wasps are a family with brood care, similar to the digger wasps or clay wasps, but they specialize in spiders as prey. Seeing the fight between wasps and their dangerous prey can be phenomenal. Having chosen a site for her nest she digs a tunnel and camouflages it as to not loose it to thieves. She then flies back to the stunned spider and walking backwards she drags her bounty over the rough ground to the hole.This hole, may I add, can be meters away. From time to time she may leave the spider and fly to the hole, possibly refreshing her memory or perhaps to have a breather.

When she eventually arrives at the hole she pulls the spider down into it and lays her big, white oval egg on its abdomen. Some wasps ensure immobility by biting off the spider’s legs. With that out of her system, she comes out and fills the hole by scraping soil into it, levelling off the surface carefully and dragging small twigs and dead leaves over it so that no trace of her nest is visible.She flies off and repeats the process.She might bring her next victim to the same spot, burying it close beside the first or she might make her next nest some distance away. It all depends on where the next hunt takes place.

The eggs hatch about 10 days later and the larva feeds on the paralyzed spider. The spider will provide food for the entire life of the larva. By the time the spider has been consumed only the legs and skin remains.The larva is now fully grown and it begins to spin a dense cocoon of brownish silk.It now cleanses it’s alimentary canal of waste matter, the stomach opening into the intestine for the first time. It then lies there motionless in the cocoon for months, until the arrival of warmer weather. Summer triggers pupation which carries on for 2-3 weeks at which point the adult wasp emerges.