butterflies drink nectar
BUT THEIR CATERPILLARS NEED LEAVES
BUT THEIR CATERPILLARS NEED LEAVES
BUTTERFLIES IN DECLINE
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Why are Numbers Falling?
Butterflies and other invertebrates bring the countryside, a park or garden to life, but many of us will have noticed a fall in butterfly numbers over the last few decades. No, it's not our imagination; detailed surveys support our suspicions. Butterflies and other invertebrates are being wiped out as their habitats are destroyed, and the specific wildflowers on which they feed and seek shelter are lost. The situation in Britain is similar to that in most other countries in that the main causes of habitat destruction and the consequent loss of wildlife are the relentless intensification of agriculture and increased urbanisation. Agricultural intensification The destruction of hedgerows and dry stone walls to create ever bigger fields, soil preparation techniques, the draining of marsh land, and the development of aggressive crops which choke out everything else in their path is bad enough. But followed by the application of insecticides and herbicides it results in widespread starvation in the insect world and among the birds and mammals that feed on them. More and more of the Earth's surface becomes a dismal barren landscape designed for ever bigger machinery. A typical field is now a wildlife desert. Insecticides Crop protection involves the direct killing of insects by insecticides, much of it indiscriminate, with no regard to whether they are actually the species causing the damage, or predators of them. Herbicides But far more harmful overall is the effect of herbicides targeted at the native vegetation on which butterflies and their caterpillars, and countless other invertebrates, feed. Without food, nothing can survive. Increased urbanisation There are of course other causes of declining biodiversity. Road building is one. The duelling of the A90 in Scotland for instance is causing habitat destruction on a massive scale, while increased urbanisation produces housing estates with virtual gardens where soil is replaced by block paving, and flowers by a bunch of brightly coloured cars. OUR AIM Our aim at CATERPILLAR FOOD PLANTS is to suggest ways in which we can slow down the rate of destruction and bring back the butterflies by growing more of the native wildflowers and leafy vegetation essential for their survival. Adult butterflies drink nectar and/or other sugary drinks, but their caterpillars need their greens. And when they are in short supply, we need to provide them. 
Wildflower Meadows Providing Nectar and Pollen for Bees and Adult Butterflies
There has been a lot of interest in recent years in the sowing of wildflower meadows, and wildflowers in general, to help meet the nectar requirements of adult butterflies and the dual nectar and pollen requirements of bees. This is excellent, but It's worth remembering that of the thousands of species of insect native to Britain, not all actually drink nectar or eat pollen, just the high profile pollinators - butterflies, moths and bees, hoverflies and a few others, and then with very few exceptions only as adults. Bees are one such exception. They are extremely unusual insects in that as adults they feed on both nectar and pollen, and their larvae do the same. Butterflies and moths in contrast - with a few tropical exceptions - do not consume pollen at all, and some do not even drink nectar, preferring to refuel on aphid honeydew or rotting fruit. Those butterflies that do drink nectar, do so only as adults, their caterpillars having a completely different diet. Many insects feed on neither pollen nor nectar at any stage of their lives. Beyond the Nectar - Caterpillars Need their Greens We encourage visitors to our website to look beyond the nectar and to appreciate the needs of butterflies and moths at all stages of their lives. This begins with the laying of eggs by the females after a careful search to find just the right plant and location, taking into account the needs of her caterpillars for nutrition, warmth, camouflage, and defense. 
We therefore emphasise the importance of providing not only adult butterflies with nectar but their much more selective caterpillars with the special diet that they need.
So long as they can reach it, adult butterflies don't particularly care what flowers they get their nectar from, but they do care what kind of leaves or buds they lay their eggs on. This is because their caterpillars can only eat the leaves of a very small number of different kinds of plant, in some cases they are limited to just one species. There are various reasons for this:
These caterpillar foodplants are not necessarily present in the popular commercial wildflower mixes that supply the flowers for pollinators simply because a lot of such foodplants are wind pollinated and so don't produce meadow-ready pretty flowers, and there are others that for one reason or another rarely appear in wildflower nectar mixes. The good news, however, is that it would be difficult to find a component of a wildflower mix that wasn't a larval food plant for one insect or another. Each is virtually guaranteed to boost biodiversity beyond its own presence. There will also be a need, to be discussed later, for suitable pupation and hibernation sites in crevices in trees and among clumps of vegetation.
A Bio-diverse Green Garden or Block Paving; Which Would You Choose?
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Butterflies are often regarded as an indicator of the health or otherwise of the countryside - what happens to them is likely to be happening to thousands of other equally important but perhaps less flamboyant and colourful insects. It is encouraging to realise that whatever steps we take to help bring back the butterflies, even if the butterflies themselves fail to respond to our offer of appropriate foodplants, our actions are still likely to be of benefit to many other kinds of invertebrate.
At Caterpillar Food Plants we aim to Increase Awareness of the Wildflower Foodplants Essential to the Survival of Butterfly Caterpillars, and to Provide Help in Selecting those most Suitable for the Butterflies Present in your Part of Britain and Ireland.
For more information about the butterflies mentioned in this website and others we recommend Butterflies of Britain and Ireland by Jeremy Thomas and Richard Lewington, 2019, ISBN 9781472967190.
The following websites also contain lots of useful information.
www.ukbutterflies.co.uk
www.butterfly-conservation.org
Text copyright Trevor Smith April 2019
The images that are not my own are from photographers who generously make their photographs available via Pixabay.com.
The following websites also contain lots of useful information.
www.ukbutterflies.co.uk
www.butterfly-conservation.org
Text copyright Trevor Smith April 2019
The images that are not my own are from photographers who generously make their photographs available via Pixabay.com.
Beyond the Nectar
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