What a wonderful find! - Hawk Moth Caterpillar

Hawk moth caterpillar in a pot of Arum Lilies, now stripped of their leaves - Pic taken in my daughter's garden in Ballito, KwaZulu Natal, South Africa

This is the caterpillar of the Hawk moth, (family Sphingidae), also called sphinx moth or hummingbird moth, sitting on the left-over stalk of an Arum Lily. Butterflies and moths, as innocent as they appear, have a definite sting in the tail. To enjoy their intricate colours, their delicate dips and swings across the sun-kissed garden and their evening hovering among scented blooms, we have to live with their myriad off-spring which chomp, chew and generally deface our carefully tended plants, shrubs and trees.

Silver-striped Hawk moth (pic from "Butterfly conservation")

One of the most voracious of these is the caterpillar of the Hawk Moth, which can strip a plant of all its leaves in a matter of days. The Arum lily is one of the host plants for Hippotion celerio, commonly known as the Silver-striped Hawk Moth or Grape Vine Hawk Moth. This is an exceptionally handsome, neat looking moth with a wingspan of 76 mm and longitudinal pale brown and olive-brown stripes along the body and wings. The Arum lily is one of the host plants for this moth. These moths are widespread and abundant in Africa, breeding along the North and East coast and subsequently colonising southern Europe.

Hawk moth caterpillar in a pot of Arum Lilies, now stripped of their leaves - Pic taken in my daughter's garden in Ballito, KwaZulu Natal, South Africa.

This resident moth flashes reddish-brown patches on under-wings if disturbed. The wings can sometimes have a pinkish/purplish tinge. Adult, with a wingspan of 6.5 - 9cm, can be seen flying between May and early August.

Hawk Moth caterpillars are medium to large in size, with stout bodies and five pairs of legs. Usually the hawk moth caterpillars’ bodies lack any hairs (he/she was beautifully smooth to the touch!, and most species have a ‘horn’ at the posterior end (seen in the top photograph). Many are greens and browns, and have counter-shading patterns that help to conceal them. 

Female hawk moths lay translucent greenish, flattened, smooth eggs about the size of a tomato pip. These are usually laid singly on host plants and take between 3 to 21 days to develop. Most species are capable of producing several generations each year if weather conditions suitable.

The eggs hatch out into pale green caterpillars about a centimeter long. They hide under the leaves during the day but eat ravenously and grow at an alarming rate at night. As they grow their colour darkens darkens slightly and they lie along the upper stem of the arum where they blend perfectly.

A week or so later the teeny, cute little green caterpillar will be  staunch 7 or 8 centimeters long, turn brown and descend to the base of the plant where once again it will blend perfectly with its surroundings. Here it may spend the day in hiding, creeping up during the night to continue its depredations.

Next morning - Hawk moth caterpillar resting on the edge of the plant pot

The damage to the arum lilies was the loss of their leaves which admittedly hindered their growth but they recover. To save your Arums, visit them regularly and check for eaten leaves and along the stems, where you will find the culprits.

Before you go on the rampage, consider the results of your actions.

So now it's up to you. You may decide to pick off and destroy both the eggs and the caterpillars, but bear the results of this action in mind: birds will find less food in your garden and may leave to find food elsewhere, night blooming flowers will not be pollinated and bats will be deprived of a protein packed 'snack on the wing'.

Although appearing delicate, the eggs are surprisingly strong and difficult to crush.

This Pic from Kumbulu Nursery

New life

Summer is the time of new life - baby chicks and  birds are hatching, my bathroom court-yard garden is full of new baby lizards and virtually every day I witness the birth of something.

Yesterday morning, as I was packing my garden tool basket, I came upon a spent cocoon and it was rather large, almost three inches. I wondered what on earth could have hatched, obviously a moth and I hoped she was still around somewhere. A search revealed her sitting on the edge of the patio step, trying to unfold her shrivelled wings. I quickly picked her up and carried her to the nearest tree, and only afterwards thought that I should have taken a photo of her before picking her up!

Once in the tree she started crawling up and vibrating her wings, making it very difficult to get a photo!

She's not this blurry in real life! Even while sitting still for a moment, her wings were trilling and vibrating, pumping blood through to strengthen them. I've come to the conclusion that she's one of the Hawk moths but have not been able to find a positive identification (there are 7 000 species of moths in South Africa!)

The Sphingidae are a family of moths (Lepidoptera), commonly known as hawk moths, sphinx moths, and hornworms; it includes about 1,450 species. They are moderate to large in size and are distinguished among moths for their rapid, sustained flying ability. Their narrow wings and streamlined abdomens are adaptations for rapid flight.

Some hawk moths, such as the hummingbird hawk moth or the white-lined sphinx, hover in mid-air while they feed on nectar from flowers, so are sometimes mistaken for hummingbirds. This hovering capability has evolved only four times in nectar feeders: in hummingbirds, certain bats, hoverflies, and these sphingids (an example of convergent evolution). Sphingids have been much studied for their flying ability, especially their ability to move rapidly from side to side while hovering, called 'swing-hovering' or 'side-slipping.' This is thought to have evolved to deal with ambush predators that lie in wait in flowers.

And now there's a spin to the tale. As soon as I finished photographing her and had moved away, I noticed my Robin in the tree, hopping from branch to branch, trying to get a good look at what might be the biggest snack of the week! I immediately climbed up the lower branches of the tree, retrieved her and took her to another tree at the other end of the garden, hoping the Robin didn't know what I was doing. Upon my return to the patio, I noticed the Robin still hopping around in the tree, trying to find out what had happened and where that snack has disappeared to all of a sudden! Hopefully he, or any of the other birds, won't find her hidden in the foliage of the other tree.

Just before dusk I checked on her, and she was quietly hanging onto the trunk of the tree, quite well camouflaged, so hopefully she would be safe until night time. All moths are nocturnal and some species fly only for short periods either around dusk or dawn, while other species only appear later in the evening and others around midnight, but such species may occasionally be seen feeding at flowers during the day. A few common species in Africa, such as Cephonodes hylas virescens (the Oriental bee hawk), Leucostrophus hirundo, and Macroglossum trochilus, are diurnal.

Most species of Hawk moths are multivoltine, capable of producing several generations a year if weather conditions permit. When I checked early this morning, she was nowhere to be found and hopefully she survived the dangers of the night. And maybe I'll be seeing a lot more of these moths in the future.

.