The RSPB's Mike Shurmer gives the low down on how to get the most out of a garden bug hunt. Get ready, get set, go...
Surveying insects can be an expensive business, with entomologists often spending hundreds of pounds on specialist equipment like moth traps, sweep nets and vacuum samplers. It can all be a bit daunting! But it is possible to find plenty of insects and other invertebrates in your garden with a few simple cheats and the unwanted materials you may have lying around. In this blog, I hope to give you a few simple ideas to help boost the number of insects you can find on your next bug hunt.
Sitting and watching
Credit: Andy Hay
Often the best thing to do first on a bug hunt is to find some flowers in a sheltered sunny spot and sit and watch for ten minutes. Garden flowers like primroses, forget-me-nots and grape hyacinths can be very productive (as can the blossom of fruit trees if you have one). Look out for hoverflies, bumblebees and the wonderful Dark-edged Beefly using its proboscis to feed as it hovers!
Build a pitfall trap
Credit: Eleanor Bentall
Next, install a couple of pitfall traps to check in a few hours’ time. These simple traps involve digging a small hole, placing a container in the hole (an old yoghurt pot is perfect) up to ground level, place some dead leaves for cover in the bottom and use a tile to keep out the rain. Remember to check regularly and release your catch. Instructions are here https://www.nhm.ac.uk/discover/how-to-make-pitfall-trap-to-catch-insects.html.
Deadwood and stones
Credit: Neil Harrison
Piles of dead wood and old stones can create perfects homes for insects like ground beetles and earwigs. Take your time to carefully turn over old logs and stones to search for what is underneath, replacing material as you found them. See here for tips on how to build your own woodpile https://www.rspb.org.uk/get-involved/activities/give-nature-a-home-in-your-garden/garden-activities/bringyourgardentolifewithdeadwood2/
Build a bug hotels
If you have materials like some old hollow bamboo canes, bark, dried plant stems, broken terracotta pots etc… you can stack these between wooden pallets, or even just old planks separated by old bricks to build a bug home https://www.rspb.org.uk/get-involved/activities/give-nature-a-home-in-your-garden/garden-activities/build-a-bug-hotel/. I had Red Mason Bees investigating the bamboo canes at my bug hotel within hours of making it last spring, so the results can be rapid!
Who’s eating your leaves?
Checking leaves of herbaceous plants may reveal holes created by feeding caterpillars, check the plant carefully to see if you can find the culprit. In my garden I currently have scarlet tiger moth caterpillars eating the leaves of alkanet and comfrey. If you have bramble in your garden you may be able to find the feeding signs of the micro-moth Stigmella aurella, the larva of which creates long sinuous ‘mines’ in the leaves as it feeds on them.
Climbing up the walls
Where you have the sun hitting the outside walls of your house, or other hard surfaces such as fence panels or garden furniture, it is worth regularly checking these for basking insects taking advantage of the retained heat. I frequently see bugs, beetles and flies on the walls of my house.
Be more yellow
One of the basic concepts of insect traps is that many insects are attracted to yellow surfaces. If you have any old bright yellow clothing, perhaps an old frisbee or plastic bowl, or ideally something covered in yellow UV paint, place this in a sunny patch in the garden and see what lands on it.
Sorting through the litter
Do you still have piles of old leaves in a shady corner of your garden, perhaps you have a leaf trap or a compost bin? These can be great places for insects, which will be breaking down this material. Get an old white sheet, or tray and place this on the ground. Place a couple of handfuls of leaf litter or compost on this (gloves recommended), spread it out and watch for a few minutes. You may start to see small invertebrates like centipedes and beetles moving around. Replace the material where you found it.
Moth trap on the cheap
Credit: Rosemary Despres
Finish your bug hunt by moth trapping on the cheap. Whilst professional moth traps with special bulbs are the best ways to record which moths are present, there are plenty of other techniques to try out on warm, still, cloudy nights to find moths and other nocturnal insects:
Remember, if you are using LED torches or lights then be careful not to stare directly into the light. See here for more information https://www.bbc.co.uk/blogs/natureuk/entries/bd7c6a4e-dad9-384a-89a0-1b7a93660d72
Tell people what you find
Sightings in gardens can tell us a lot about the health of insect populations and changing distributions. There are a whole range of Facebook groups for various types of insects and if you identify something then you can post your sightings, with a photo, onto iRecord https://www.brc.ac.uk/irecord/ to get into our national datasets.