Wild Spood: Insect Sampling Edition

Whilst going about my work day this Monday, I happened across this Wild Spood. She might be difficult to identify in this photograph, as she is a very dark brown - almost black - Steatoda species of spider. My first thought was a false widow, but she seems a little too dark for that. Regardless, what we have here is a very defensive mama spider who is protecting her egg sac. After running towards me once I picked her home up, she turned around and ran back to her sac - putting several long legs over it to keep it safe. It's okay Mama, I'm not going to touch your brood.

But what this does do is give me the chance to talk about one of the aspects of my work - insect sampling. This spider has unfortunately made it's nest inside the cover that I use to test trigger the moth light trap that I use at work. I'm not sure whether this is more unfortunate for me, as it leaves me open to getting bitten whenever I test my moth trap, or the spider, who is going to be disturbed twice a week as we go about our biweekly checks... This is the moth trap:

There is a network of these moth traps all across England, Scotland and Wales, all run by the Rothamsted Research insect survey. As the light dims, the trap is activated and it switches a light bulb on. The moths are attracted to this light, where they are then caught in a container. I come along, collect this container, and then send the moths to Rothamsted for counting and identification. The container is then replaced, and the trap is set again.
By collecting this data we are able to tell a number of things. We can tell the number of species present in the area, along with the proportions of those species. It helps us to identify range changes as species migrate to different areas, something that can be caused - amongst other things - by climate change. It also helps us to tell how healthy a population is - a vital piece of data in a world where species are dying off faster than ever before. We can tell if invasive species are enetering the ecosystem, and what effects they may be having on the native species. For example, from this research we can tell that in the 40 year period between 1968 and 2008 the total number of moths in the UK declined by 28% - A loss felt even more by Southern counties which lost up to 40% of their moth abundance. Northern counties had a lower total decline as their losses were offset by Southern moth species moving North.

The second part of my insect sampling comes in the form of an aphid suction trap:

These towers are built, owned and run (again) by the Rothamsted insect survey. And once again, there is a vast network of them around the UK. They are designed with a motor that generates a suction effect, effectively "hoovering" a one foot cubed area of the air. They are built to be tall, sucking migrating aphids out of the air and depositing them into sample pots in the heart of the machine. The pots are changed daily, and sent to Rothamsted who process the information. By analysing this data, we can again see the changing populations of migrating and seasonal aphid species. This data is vital to the farming, floristry and agricultural industries.
There are no two ways about it - aphids are a pest. As are some moths, to be fair. Whether they're decimating crops and hedgerows by consuming everything in sight, or spreading plant diseases from sick plants to healthy ones, these insects have a dramatic effect on the cultivation and yield of plants and crops. It is possible to control this factor through the use of pesticides, but pesticides don't just kill pests - they kill pollinators and innocent species too. Too much pesticide use can result in the pests becoming immune to the chemicals, making them useless in the end. Finally, pesticides may make the end concumer - us - ill, by being inhaled, ingested, or absorbed through our skin. Overall, pesticides are bad.
By collecting this longterm data, scientists can predict when the most damaging species populations will boom or bust, and thus can advise on the timing of those one or two pesticide applications per year, to achieve the best results. Personally, I am very happy to be part of something that's so important, even if it doesn't garner a lot of attention.

For more information, please visit Rothamsted, where you can find the information about both sampling endeavors, and archives of the data collected from every insect sampling point.

Happy Reading!