Day 2- Spiders

Today we went out with the spider team and had SO MUCH FUN,

we learned a lot about spider behaviour and gained a deep respect for the so-called creepy crawlies of the forest. There are many different sampling techniques that can be used to collect spiders. The most common is the classic rock/log flip that many surveyors use to find different species such as ants, termites and skinks.

A new technique we learned was vibration, we ran the van next to the road and the spiders and cockroaches are attracted to the vibrations and come and investigate where we scoop them up in vials to be examined. In one location the spider density was so high we were practically swarmed by them. It was awesome.

Today’s highlight though came when we returned back to camp and arranged a romantic rendezvous for an undescribed species of spider! Couples from two different species from the same genus were allowed to mingle with each other. The first ones were more combative, wrestling a bit and standing in a tableau before deciding to mate.

The second couple were not keen on each other, so the female was removed and another one was introduced- and it was love at first sight! The male and female crashed into each other and began to mate. During mating the male covers the female’s face in his web, it is hypothesized that they use this as an anchor point, or to prevent being bitten by the female during mating. What’s your hypothesis?

Male genitalia or sex organs are located in the paddle-like pedipalps at the front of the spider. Pedipalps are unique to each individual species and are used to identify species. Observing this behaviour is incredibly difficult in the wild which is why it’s so important to facilitate it in the lab when the opportunity arises.

https://en.wikipedia.org/wiki/Pedipalp#/media/File:Oxyopes_salticus_Kaldari_05_crop.jpg

Pedipalps in image are not from our species, but is an excellent example of how they look.

(Matías A. Izquierdo , Gonzalo D. Rubio - (2011). "Male genital mutilation in the high-mountain goblin spider, Unicorn catleyi". Journal of Insect Science 11. DOI:10.1673/031.011.11801., CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=39524855)

We ended the night on a short hike around Birrigai looking for wombats- no luck though so we’ll try again tomorrow!