BugWise

Water droplets glisten in the sunlight which allows easy detection of webs. Photo: J Gollan © Australian Museum.

Spiders are considered an important invertebrate predator. Museum scientists have shown that there is a good relationship between web varieties and the number of different spider species. This method provides an easy way to measure the numbers and diversity of spiders that build webs to catch their prey.

What you will need

• Water mister. Do not use the bottle if previously filled with fertilisers or pesticides.
• Web2Spider guide
• Pencils and data sheets for recording.

Method

• Describe your site.
• Slowly walk through your site and spray water in front of you and one metre either side of you. Carefully look out for any webs that glisten as the sunlight catches the water droplets. Use the spider web diversity key to identify web type.
• Record your methodology. For example, did you walk in a straight line and how long did you walk for.

Tips

• Do your surveys as early as possible. Just after sunrise is ideal. This takes advantage of the morning dew and limits the need for you to spray water. Webs are also likely to be damaged or destroyed as the day progresses.
• These surveys are easier to do with two people - one person to use the water sprayer and the other records the information. Both people can search for webs.
• Avoid windy and overcast days. Try to do your web surveys on sunny clear days. This takes advantage of sunlight, which causes the water droplets to glisten.