For me, every week is Insect Week. I absolutely love insects. You can often find me walking around the Botanic Garden in my insect-themed t-shirts with my face stuck in flowers looking for any interesting ones! Since I’m so passionate about insects, I get a bit disappointed about how overlooked their importance is. Different insect species can have different roles in ecosystems and are vital to the survival of many other species.
Pollination is one very important role that insects carry out, and it is crucial to the reproduction and therefore the survival of many wild plant species, as well as our crops, such as tomatoes and oilseed rape. Insects carry out pollination by transferring pollen from the anther of a male flower to the stigma of a female flower while they forage for nectar and pollen. Pollen sticks to their hairy bodies, which makes transfer more effective. This is why fuzzy bumblebees are such effective pollinators!
Also, when a lot of people think about pollinators, they tend to think about bees. However, there are lots of other insect species that also carry out this role, such as beetles, wasps, butterflies, moths and flies. Steven Falk has estimated that there are actually around 6,000 species of pollinator in the UK, and only approximately 270 of these are bees! One of my favourite pollinators is the adorable bee beetle (Trichius fasciatus), which can often be found on flowers like ox-eye daisies and bramble. They are called this because they mimic the appearance of a bee. This is a great example of Batesian mimicry, which is where an animal adopts the appearance of a more harmful animal to avoid predation. They’re even fuzzy like a bee, which means that they can pick up a lot of pollen on their bodies.
Beetles and flies are responsible for helping rid the earth of waste, such as faeces and decaying organic matter. Dor beetles (Geotrupes sp.), for example, help break down faeces left by animals like sheep and deer. They do this by laying eggs in a burrow under animal faeces and then, when the larvae emerge, they feed on the faeces, therefore helping clear it up. Flies, such as the yellow dung fly, also lay their eggs in faeces so their larvae carry out a similar role to that of dor beetles. There are also beetles called carrion beetles, and these break down dead animals, such as birds and small mammals. An example of this is the black sexton beetle (Nicrophorus humator), which digs beneath dead animals, making them gradually sink into the ground where they will decompose. As a result, we have beetles and flies to thank for getting rid of the smelly stuff.
Insects are also excellent at pest control! For example, hoverfly larvae, lacewing larvae and ladybirds are predators of those pesky aphids that always seem to head for your best roses. Wasps are also predators of lots of insect species like greenfly, and therefore help to keep their numbers in check. If you attract these species to your garden, such as by planting more insect-friendly plants and creating insect log piles, your plants should escape a bit more insect damage, and you shouldn’t need to use pesticides, which are harmful to many animals.
Some animals, such as birds and hedgehogs, are reliant on insects as their main food source. For example, blue-tits eat caterpillars, as well as feeding them to their chicks. Climate change is resulting in nests becoming short of food, as caterpillar numbers are decreasing and they are emerging at a different time to when blue-tits are nesting (Pollock et al., 2017). This really demonstrates how important insects are to the survival of other animals.
Why insects need our help, and what you can do to help them on your own patch
Insects are in decline, due to habitat loss, pesticide use and climate change. However, you can make a difference by supporting insects in your local patch. Here are some different ways you can do this:
- Plant more insect-friendly flowers in your garden
- Add a mini meadow to your garden
- Create a log pile for insects to live and hibernate in
- Buy or make a solitary bee hotel. You can learn how to make one in Abigail Lowe’s blog: https://botanicgarden.wales/2018/07/all-about-bee-hotels-and-how-to-make-your-own/
- Build a wildlife pond, which will provide a habitat for dragonflies, damselflies and hoverfly larvae
- Stop using pesticides
- Mow your lawn in a mosaic pattern – short grass will cater to the needs of mining bees and longer grass will give insects a place to hide and any wildflowers will provide them with forage
- Leave a shallow dish of water filled with stones out for insects to drink from
- Donate to an insect charity, such as Buglife or the Bumblebee Conservation Trust
- Share what you know about insects with your friends and family
- Submit your insect records to iRecord
Pollock, C.J., Capilla-Lasheras, P., McGill, R. A. R., Helm, B. and Dominoni, D. M. (2017). Integrated behavioural and stable isotope data reveal altered diet linked to low breeding success in urban-dwelling blue-tits. Scientific Reports, 7. [Online]. Available at: https://www.nature.com/articles/s41598-017-04575-y.pdf [Accessed 18 June 2021].