Share your views on smallholding with others. Send your pictures, video, news and views by texting PKNEWS 80360
The Elephant Hawkmoth
I WAS recently contacted by a lady from the local fuchsia society. It’s amazing how many specialist groups there are in this world, surely if they meet every month they must eventually run out of things to talk about.
Anyway this lady organises guest speakers for their group and fortunately, as she explained, it isn’t their intention to have talks on fuchsias every month. Though I am sure that fuchsias are very interesting there is only so much you can learn about their cultivation, propagation and variation so, she wanted to know if I would present a talk about the wildlife of Cornwall, where this group is based.
No problem, I am only too glad to visit groups and talk about wildlife, but then I started thinking about how I could make my talk relevant to their group. The only thing I know about fuchsias is that elephant hawkmoths love them. To be more precise it is the caterpillar of the elephant hawkmoth that loves fuchsias and one of the best ways to find these weird caterpillars is to look for a fuchsia whose leaves have been liberally chomped through.
- The hawkmoth family
Before I take a closer look at the elephant hawkmoth let me tell you a little more about the family of hawkmoths. Essentially hawkmoths are just large moths but because of their increased size they are very much more impressive. There are nine species which are resident in Britain, with a further eight occurring as immigrants. They are called ‘hawk’ moths because of their fast manoeuvrable flight.
Most of them fly by night but there are some, such as the hummingbird hawkmoth, which fly by day. In fact the hummingbird hawkmoth is another very interesting species. This is a migrant, arriving here from the continent in summer, but the adults are able to hibernate over winter in the south west. Since it flies by day it is much easier to observe than most of the rest of the family, but its flight is typical of the hawkmoths. Watch the precision with which a hummingbird hawkmoth approaches a flower and inserts its proboscis into it to collect nectar. If you find that amazing consider the rest of the family who have to do it in the dark.
To manoeuvre into the correct position a hawkmoth uses raw power with its wings beating at a rate of over 70 times per second. Compare that to a butterfly whose wing beat is only usually around nine beats per second. Hawkmoths are attracted to pale coloured flowers which release strong scent at night, or more particularly at dusk when they are most active, such as honeysuckle and night-scented stock.
They are also attracted to lights so it isn’t uncommon to find one flying around an outside light at this time of year. I have already pointed out that hawkmoths are big moths but it isn’t until you see one of the larger ones that you appreciate just how big they are.
- The death’s head hawkmoth
The largest is the death’s head hawkmoth, which is as gruesome in appearance as its name suggests. This species has a forewing length of up to 60mm which means a wing span of over 120mm, in old money that is about five inches.
Fortunately the death’s head hawkmoth is quite rare in Britain occurring as a migrant only in the south west. The largest resident species is the convolvulus hawkmoth which isn’t much smaller and fortunately for fuchsia lovers everywhere its caterpillars do not eat the leaves of fuchsias.
- The elephant hawkmoth
Anyway that brings me back to the elephant hawkmoth. This species is relatively small when compared to the bigger members of the hawkmoth family. Its forewing length is just 30mm giving it a wingspan just in excess of 60mm or about two and a half inches. What it lacks in size it more than makes up for in colour since its body is a mixture of olive-green and pink. The adult moths fly by night and enjoy feeding on the flowers of honeysuckle, rhododendrons and willowherbs amongst other tubular nectar flowers. They can be found on the wing throughout the summer but by late summer we are probably more likely to find their caterpillars, or more correctly their larvae (we tend to refer to caterpillars for butterflies and larvae for moths).
It is the larva of the elephant hawkmoth which earned the species its name. This bizarre looking larva has a snout which it can extend so that it looks something like an elephant’s trunk. As well as this rather unusual feature the elephant hawkmoth larva also has huge eye spots on either side of its head and a small tail. Since this larva can grow to be a couple of inches long it would take a brave predator to tackle one, it can look quite intimidating with its ‘eyes’ puffed out. These larvae can munch their way through a fair amount of foliage. They will eat the leaves of willowherbs and bedstraws but most people find them in their gardens eating fuchsia leaves. It is during this phase of their life cycle that they attract most attention because although the larvae feed at night they often laze around on the stems of fuchsias from late afternoon to enjoy the evening sun. They are big enough and strange enough to attract the attention of the more observant gardener. As we progress through September and October the larvae become fully fattened and they pupate amongst leaf litter on the ground and there they stay until the following summer when they take to the wing.
Anyway, do you think I’m on the right lines with planning my talk for the fuchsia society or do you think I should leave out the elephant hawkmoth story?