If most of us saw something like this we may be tempted to squash it, spray it or just scream.

But this scientist, not only has a special affection for spiders, she sees them as a valuable tool in helping to manage our environment.

"Yes, I love spiders. I think they're very interesting and mysterious, I guess is a good word".

According to CSIRO's Dr. Tracey Churchill, most people fear spiders because of the very few that are dangerous. Ninety eight per cent are not only harmless, they are important for noting changes in their environment.

"Their role is to reflect as predators in the small animal world what might be going on lower down in the food chain which is more complex and often more harder and more expensive to measure".

For over 15 years, Dr.Churchill has been studying spiders around the Northern Territory. She uses methods such as pitfall traps which are set 10 metres apart in a grid.

Each group of spiders eats different types of prey and uses different parts of the environment at different times of the year.

And since spiders are common predators, if they decline, then they are warning us that what they eat and the cycling of nutrients or health of the land is also declining.

After a week the captured spiders are taken to Darwin for identification.

In the laboratory, the spiders are identified and a record made of their distribution, numbers and relationship to aspects of the environment.

The results can then be analysed to indicate the extent or direction of ecological changes.

The data collected from the spiders can work as a barometer to monitor more complex and harder to measure information about environmental conditions and help predict changes before it's too late.