Nature 2011 August

Here Be Dragons or Excuse Me, Madam But There’s A Newt In Your Fruit Salad!

‘Here be dragons’ was a warning illustrated on the corners of old maps indicating you were leaving the known world for lands where frightening monsters lurked.

Hedgerows are at their most bountiful at this time of year. Trees, shrubs and herb plants are flowering and fruiting and in turn provide a rich source of food for caterpillars, beetles and fellow insects. For the next three months there are more birds on the wing than any other time of the year and those partial to invertebrates will be doing their best to hunt them down. Over the millennia those insects with marginally better camouflage have outwitted those birds marginally better at spotting their insect prey. The net result is some very hard to spot insects have evolved.

I spent a fair amount of time as a youngster collecting and breeding moths. – Sad I know! – Well, because of this evolution thing, finding mainly green moth caterpillars that feed on mainly green leaves or twig-like caterpillars that rest on twigs was particularly tricky. Then I came across a helping hand. There are a whole lot of small predatory insects that go by the name of Ichneumon wasps. Ichneumon means ‘a tracker’ in Greek, and in medieval times an ichneumon was the name of a mystical creature that hunted and destroyed dragons. These wasps spend their time hunting down much smaller ‘dragons’, caterpillars. These wasps do not eat them but lay an egg in each which hatches and lives parasitically off the caterpillar but not killing it or destroying any vital organs so the host continues to eat and grow. Once the wasp larvae is full grown it burrows a whole in the body of the caterpillar crawls out and pupates next to the caterpillar which spins a web around the pupae to protect it. Sometimes an even smaller ichneumon wasp tries to parasitize the other wasp larvae however, the now zombie-like caterpillar protects its incumbent by swiping away this, would be intruder. Eventually, a new wasp emerges and flies off to continue the cycle. Now what I found is if you follow them along the hedgerow they will find the caterpillars for you.

I had an email in June about a grass snake that had been sighted in the churchyard in Cholesbury. It’s just the places to hang out if you are after mice and the like and with a pond nearby, plenty of frogs and newts. It made me think that though there must be hundreds of such reptiles around us for most of the year its just summer time that we stand a good chance to see them when they come out. Not that they hang out in some kind of ecological closet for the rest of the time, it just that they appear more brazen between June and August when the ambient temperature is warm enough for them to move around in search of food. Earlier and later in the year they may struggle in the weaker sun to push their internal temperatures up to 27°C and then they only move around sluggishly. So the few reptiles that we have in this country are more likely to be out basking on open ground like sandy banks, stones and baked earth paths etc. Although elsewhere in the world, reptiles maybe ubiquitous in the not so sunny Britain we have just six, three snakes and three lizards. So apart from the aforementioned grass snake which tends to get the good press there is the adder or viper which undeservedly gets all the bad press because they have evil looking zigzag markings down the back and are venomous. As a youngster I learned, erroneously as it turned out from seeing all those ‘Westerns’ at Saturday morning pictures, that the best way to deal with a snake bite is to make an incisions with a knife and suck out the poison. Seriously if you ever got bitten keep the limb stationary and send for help, nasty still but you should survive. Mind you if you’re a mouse or vole having been bitten you will have about two minutes to live! The third snake is the smooth snake which does not get any press being neither venomous nor common being restricted to a few south coast counties from Dorset to Sussex.

The distant relative of our lizards is the Komodo dragon. Our three ‘dragons’ of which only two can be found in these parts, are the common lizard and the slow worm. Meanwhile the third, the sand lizard hangs out only in the same places as the smooth snake which is a bit of a problem as the lizard is one of the favourite preys of the snake! Lizards are insectivores (contrarily referring to eating any invertebrates, not just insects), using their tongue to catch their live food. Slow worms though limbless are no more related to snakes than other lizards its just parallel evolution at work allowing for more rapid movement through dense undergrowth than four legs would afford. Unlike snakes they have eye-lids and like other lizards can shed their tail if caught. They are excellent harvesters of slugs and snails. Actually, it is not strictly true that there are only four reptiles in the area. To these we should add the odd family tortoise which occasionally makes a ‘run’ for it from local gardens. I know of one from Bellingdon which has headed our way in the past!

I was about eight and my father and I were returning home on the London Underground late afternoon one summer Sunday. We had been visiting some large ponds in Rickmansworth purpose being to stock up our brand new small pond in our garden. My father had procured a couple of large sweet jars, the kind with black screw-top lids that used to adorn the shelves of newsagents. One of the jars contained a variety of water beetles, water boatmen, dragonfly and caddis fly larvae, the latter secreted in their cases of sticks or minute snail shells, sticklebacks and minnows and probably a few of the more exotic beasties such as a water scorpions. Inside the other jar were our two prize finds of the day. The jars were each carefully housed in their own duffel bag. As the train trundled on towards London it became quite full of passengers and our jars ended up on the overhead luggage racks opposite. It turned out our return trip coincided with revellers travelling to the Proms at the Albert Hall. Not long before we were due to get off my Father drew attention to the lady opposite who was wearing a most colourful hat after the style of Carmen Miranda. However, my Father was not so much interested in the colourful fruit and exotic looking flowers as he was the intruder that was to be seen exploring the cherries and grapes. It was a dark olive green above with a black spotted orange underbelly. Unmistakably, it was a male great-crested newts and future partner of a female that had been our most prized catches of the afternoon. These newts are part of the Salamander family and were in ancient times thought to be the young of dragons. The screw lid, loosened to ensure there was an ample supply of oxygen, had come adrift and one brave amphibian had gone exploring. Our station where we were getting off was approaching fast and I it looked as though we were going to abandon the newt to enjoy itself at an evening of serious music. Fear not as we got up and my Father grabbed our duffel bags and I heard him exclaim “Excuse me, Madam but there is a newt in your fruit Salad!” With this he leant over and extricated the beast from the hat and all three of us alighted from the train leaving one very bemused Promenader. From those two Great Created Newts a whole dynasty spread out from our back garden and then spread out to populate all the local garden ponds.