Butterflies are incredibly important to the environment because of the services they provide. These include their work as pollinators, their ability to feed on large amounts of vegetation, and the fact that they provide food for many other animals.
When it comes to what butterflies do for the environment the most obvious and most famous must of course be their role as pollinators.
A pollinator is any animal that moves pollen from one flower to another, causing cross-pollination, which allows the plant to produce a fruit or seed. Many different animals act as pollinators across the world including bats, ants, lizards and even monkeys.
However, what makes butterflies such great pollinators is that all of the 15,000 species feed on nectar as their main source of food. This means they are constantly visiting flowers, and moving from bloom to bloom.
An additional benefit is that many species of butterflies are specialised to feed on certain flowers, increasing the chances of cross-pollination from occurring as they are moving between compatible blooms.
One of the things that makes bees such great pollinators are their furry bodies, which the pollen sticks to and then fall off as they visit the next flower. While butterflies may not appear to be as fuzzy as a bumblebee they do actually have hairy bodies, and even have some hairs on their wings.
Another great thing about butterflies as pollinators is that unlike some nectavors they don’t tend to cheat. Many birds and mammals have learnt to take shortcuts by biting holes in the base of flowers or pulling the flowers off the plant to suck out the nectar, however, this means they do not spread the pollen between different plants. Butterflies by comparison play by the rules, helping to spread the love.
All butterflies come from caterpillars, a fact which we learn at a young age. These little insects are voracious in their appetite. Feeding is vitally important to move them on to their adult stage.
The vast majority of caterpillars feed on leafy vegetation. Though individually tiny, it is amazing what devastation a large group of caterpillars can achieve. Most gardeners will have watched in horror as one of their favourite plants steadily disappeared.
While we may not enjoy the caterpillar’s hungry chompings at times they are an essential part of the ecosystem, helping to recycle nutrients from plant matter into the soil by creating caterpillar poo, known as frass.
Another benefit of the caterpillar’s appetite is that it can help to create a more diverse floral ecosystem, as more dominant plants may be reduced in number as they will support a larger caterpillar population. This allows less numerous plants more spaces and nutrients.
As well as being hungry feeders themselves caterpillars are also food for other species. In many temperate zones, the flush of caterpillars in the spring is a really important food source for many species of birds and other mammals.
Birds use these plump caterpillars to feed up their chicks, and poor caterpillar years can result in poor chick survival. Worryingly climate change is causing the availability of caterpillars and the timings of the birds nesting attempts to go out of sync, which would have serious consequences.
Many species of caterpillars have truly fascinating relationships with ants. In some cases the caterpillars are simply a parasite, using the ants for food and shelter without giving anything in return. Many blue butterflies trick ants into taking them into their nests, where they will feed on the ants stores, or even eat their young.
Other caterpillar species bribe the ants to allow them to feed on plants the ants would normally protect. They have special glands that produce a sweet liquid the ants are addicted to. While such sneaky behaviour would seem like it can’t have any kind of benefit it does create a kind of balance, providing setbacks for ants that are so incredibly successful that they can easily become a dominant species in many habitats.
Many of us may know that miners used to take canaries down into the mines with them. The canaries, being so much smaller than the miners around them, were more sensitive to fumes emerging from the rocks. If the fumes started to build to dangerous levels the canary would die, and the miners would know to get out as quickly as possible.
Just like these ill-fated birds, many species can be early warning indicators that something is going seriously wrong with our environment. Insects are particularly susceptible to changes, and species can drop or rise in numbers very quickly. Today we often talk of the loss of butterflies. These losses are largely due to the over-use of pesticides and changes in land use meaning there is less food and shelter available.
Butterflies are particularly useful species to monitor as they are so visible and easy to survey. By comparing data over many years we can start to see positive or negative trends. Interestingly not all species of butterflies have been dropping in numbers. Some have expanded their ranges and become more numerous. This appears to be due to climate change opening up new areas for them to live in. Conversely, some species that are at the edge of their liveable range are running out of land and will soon face extinction.
By paying attention to what butterflies can tell us we can know when we’re heading the wrong way and need to make changes to our environment.
Equal in the eyes of nature
As humans, we have a tendency to want to rank things in terms of one being better than the other. When it comes to animals we like to pick out our star species in terms of what they provide for the planet.
However, in reality, species cannot survive individually. While butterflies may be amazing creatures they require the flowers to feed on, which need the worms to turn the soil, while needing the animals and plants that provide the nutrients for them to break down, and so on.
None of these species can survive without a multitude of others doing their own jobs. It’s therefore important that we help the whole network to thrive rather than picking our favourites and only working to protect them.