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Category Archives: Reptiles

A Blitz on Biology

Some weeks a photograph just leaps out at me that, no matter how tenuous the link, I simply have to use it for the article. This is one of those weeks.

This stunning shot of a hummingbird hawkmoth was actually snapped across the boarder in Dorset, but its an insect which is becoming increasingly familiar across the South of Britain, especially in East Devon. Local press photographer Alex took this shot of a hummingbird hawkmoth as it fed from valarian flowers, in its characteristic manner which gives it its name.

A hummingbird hawkmoth drinks nectar from the flowers of red valarian. Photo c. Alex Walton

As soon as I hear a report of a hummingbird being seen in the vicinity, I know a hawkmoth has made it across the channel and has been seen feeding. 
This day-flying moth attempts to satisfy its insatiable hunger by feeding on the sweet nectar of flowers, using an enormous proboscis tongue to suck the sugary fluid deep from within the bloom. Just like a hummingbird, it hovers a few centimetres from the flower and dips its tongue from a distance, wings a blur and its bright orange tail flashing, its easy to see how this little insect is sometimes confused with a tiny bird.

It is glimpses of exactly this wierd and wonderful biodiversity, that an upcoming event on the Axe Estuary Wetlands intends to bring to life. An ever popular event elsewhere, this will be the first BioBlitz hosted by the East Devon District Council Countryside Service. A BioBlitz is a period of 24hours when everything that grows, walks, crawls, slides, swims or flies on a particular site is surveyed and recorded.

For the visitor it is an amazing chance to visit a nature reserve with a host of experts, and for those of us who manage nature reserves, it gives us an invaluable record of all those strange, esoteric and complicated groups of plants and animals we had no idea about!

By working with my good chums at Natural England, I have managed to secure the services of some of the country’s leading experts in their field. These are the people who don’t just know about the big, the brash and the obvious; these people know about the odd squidgy bits and pieces other people overlook. We’re in for a fabulous time.

The event kicks off on Saturday 30th July at 9pm for a guided walk around Stafford Marsh in search of bats. Local ecologist, mammologist and licensed bat surveyor Ian Crowe will take us on an illuminating walk in the gloom to find the various species of bat which call the reserves their home.

Considering that we have the rarest bat (and therefor the rarest mammal) in the country living just a few miles up the valley in Holyford Woods Local Nature Reserve, it is something of an ambition to record Bechstein’s Bat on the Axe Estuary Wetlands, perhaps we’ll encounter one tonight?

Overnight, Fraser and I will be running a moth trap, sampling the diversity of moths which fly over the marshes at night. The following day we will be starting early for a moth breakfast, where local moth experts will come along and help us identify everything which ends up in the traps.

When I run a moth trap, either for work or pleasure (yes, my job does have massive cross-overs with my hobby) I end up overlooking at least 60% of the contents, deciding to leave the small micro moths and flies to another day. On Sunday morning it will be crunch time as we attempt to work out what everything is, however quirky. After the moth breakfast, the rest of the day will see scientists, and naturalists scouring the reserve, accompanied hopefully by large crowds of people interested in learning more about our local wildlife. I certainly will be hanging on their every word.

Birds, mammals and reptiles are pretty well studied on the site, so a few walks to look at these groups will be included, but it will be the less eye-catching groups which will no doubt prove the most interesting. I have something of a mental block when it comes to scientific names, and much of what will be found will only be known by its scientific or Latin name.

Please don’t let this put you off, as I intend to make it my day’s task to assign a ‘common’ name to everything we find. Episyrphus baletatus is a mesmeric little hoverfly, known more widely as the marmalade fly, so why aren’t more little flies given such memorable local names? Come along and help me come up with the couple of hundred new names which might be needed if we really strike lucky on the 31st July and hit a rich seam of form in finding creatures.

The new facilities on the Axe Estuary Wetlands will be put through their paces too, as it will be the first time we really use the Field Studies Base for its intended purpose. The solar array will be working overtime to power microscopes, as people identify those odd spiders which can only be clinched by looking at the shape of their genitalia, while the stove will be cranking out a few hundred gallons of tea to keep all those involved fully refreshed throughout their hard work.

I am looking forward to this event possibly more than any other this year, its everything I enjoy about natural history: there’s always something new to get your teeth into!

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Posted by on July 29, 2011 in Birds, Insects, Reptiles

 

A compromising position

My workplace, like so many others in the UK has a very tight policy regarding internet and email use. The policy document is good and thick and everyone who uses computers, which is all of us, must abide by these guidelines to ensure our conduct is above board.

In the normal course of events things run like well-oiled clockwork; information passes into me and I churn a multitude of things outward. Sometimes however, things get caught inadvertently in the net. The way in which computer security systems work means that some documents I receive will contain flagged words, for example  I was once sent a highly scrutinised report about woodland birds which contained too many references to the perennial favourite Parus major.

There are also some photos which are sent to me containing a large percentage of flesh tones. Autumnal heaths are notoriously tricky subjects for photo composure, and if some of the more heavy-handed IT filter systems are to be believed, they are also a hotbed for carnal  imagery too. Seldom the case with the photos I receive, I assure you.

Sometimes however, a photo evades the censor’s scrutiny and I gets through to my inbox. One such snap dropped in to my email system last week from a trusted source, which I was only glad I opened in a deserted office, such was its content. I was moved to send it in to the local paper.

So what caused all the hubbub? This fabulous picture of a pair of mating lizards, that’s what.  Despite their name, the common lizard is anything but common, and this behaviour is seldom seen, let alone captured on camera. The lucky cameraman photographed the pair in his garden, which is a timely reminder of the value of our backyards for wildlife.

Common Lizards mating - Bob Dark

As with another reptile which lives in northern climes, the adder, common lizards give birth to live young rather than lay eggs like most reptiles.  Viviparity, the birth of live offspring, allows the lizard to control the temperature at which the developing young are exposed to, through behaviour of the gravid female. If she detects that her core tempertature is low, she can bask in an open position to raise her body temperature. If she is too hot, she will retreat to a shady spot and let herself cool down. In the cool climate of the UK, it is seldom overheating which is the problem!

The young are born in July, between 3 and eleven individuals in thin eggs sacks which split as soon as the female has deposited them. The tiny, dark coloured babies are immediately very agile and will dash off into their habitat to develop unaided by the parent.

Males and female common lizards can be told apart by the pale, less speckled body colour, and the female’s wider belly size, which can be seen to physically bulge with developing young towards the end of June.

If you are lucky enough to see a common lizard handled, then the brightly coloured belly of the male is stark contrast to the female’s paler and un-speckled tum. However, you should never attempt to handle a lizard in the wild, as they are very delicate, fast-moving and difficult to catch safely and unless you are well-practiced you are very likely to harm the animal if you try to grab at it.

Better to sit quietly and watch the lizard through binoculars. If you approach slowly and calmly, a common lizard will often allow you to approach it in its favourite basking position to within a few metres. Got too close, too quickly however and the lizard will disappear out of view into the vegetation nearby.  However, do not lose heart, as they are dependable in their ensuing behaviour too. Back up a little and wait for the lizard to reappear. If you remain still, it will not notice you and will return to the same basking position as you found it in.

So to any of you budding photographers out there, by observing a little patience and guile,  you can capture good close up photographs of lizards without the need to get too close or interfere with them. Just sit tight and wait for them to come back to you.

East Devon is blessed with many very good places for reptile watching, the pebblebed heaths are a haven for many species of reptile, particularly this little fellow. Look for them on prominent features, low to the ground like rocks, or logs in sheltered spots on south-facing exposures. As ever with wildlife watching, you will need to wander about sites slowly to increase you r chances of seeing anything, and listen out too as the characteristic sound of a common lizard dashing into heather is often the first clue to a lizard’s whereabouts.

 
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Posted by on April 18, 2011 in Birds, Heathland, Reptiles

 

Snakes and adders

One of the most exciting sights in the East Devon countryside in spring must be the glimpse of an adder. Perhaps it’s a diminutive steely-grey male, with golden eye and flicking black tongue or a larger, bronzed female, opulently basking in the early spring sunshine. Whenever I see one of these beautiful animals, it sets my pulse racing.

Adders have been persecuted for years, largely due to the misconception that they pose us serious harm. However, since the killing of adders was prohibited by law their populations have continued to decline and this has got so serious in recent years as to move scientists in Oxford University to examine their genetic diversity in an attempt to unravel the mystery.

Adders are a top predator in the habitat in which they live. Feeding on small mammals and lizards, adders can only thrive where populations of these prey items are abundant. However, adders are also very slow to move into new areas, colonising – or recolonising – territories at a very slow pace. As reptiles, adders live at the northern limits of their range in our temperate climate, and so their ecology is somewhat slowed. They live a long time, and are only able to reproduce every two years, such is the stress to produce offspring. This means that with a few young being produced every other year, recruitment to the population is very slow. So once you’ve lost an adder from a site, it’s a very long time before they are likely to return.

As adder numbers wane, so populations become isolated and small clans are all that remains. Recent reports of adder malformation and abnormalities have raised concerns amongst herprtologists (scientists who study reptiles and amphibians) that this isolation could have led to genetic abnormalities through in-breeding. If a population has become so isolated that the same few adult animals are reproducing each year, and no new bloodlines are being introduced from adders nearby, for the simple reason that there are no adders nearby, then the decline of the population will be terminal.

A simple monitoring scheme has been running on Fire Beacon Hill Local Nature Reserve for three years now, keeping an eye on adder numbers, ratios of male and females and general health of the population with a series of monitoring refuges. I organise a number of reptile rambles through the year for members for the public to join in surveying the traps, giving people the chance to meet an adder often for the very first time.

When I set off on the site to lead my first ever reptile ramble, I have to admit my heart was in my throat. Was I being reckless taking a group of people onto a site which has adders, on a hunt to see… adders? I went through an extraordinarily extensive briefing before we set off, I was in serious danger of losing a few participants to boredom before we had left the car park, such was the length of my Health & Safety spiel. But eventually we got underway, and a fabulous time was had by all. As I lifted reptile traps in turn, the children at the front, adults behind, the thrill of expectation was palpable on each occasion.

Each time you lift a piece of roof felt which comprises a reptile ‘trap’ there is great anticipation for what might lie beneath. All too often it’s a large colony of ants, which means nothing else will be there. But sometimes there’s a slow worm, sometimes a common lizard and occasionally there will be the ultimate prize of an adder peacefully soaking up the heat. As long as everyone remains still and calm, gently lifting the lid on a slumbering snake will mean that it stays in its coiled position to be admired by onlookers. If people push forward to get a better view the snake will disappear into the heath behind the trap, and I will not grab out at it to pull it back into view.

The snake has done its bit and it now deserves its sanctuary, I then attempt to persuade everyone that we’ll get a better view next time if people stay still and don’t rush forward! It’s hard to convince people, but with reptiles its movement that they react to more than shape. If you stay still when reptile watching you will get far better views than by attempting to move close in. The only time in which I would intervene is if the adder decided to make good its escape toward the onlookers, which could prove rather interesting! If this happens then I’ll gently lift the snake and turn it to move away from the crowd rather than into it.

At the beginning of this article I mentioned that persecution stemmed from a misconception that adders are harmful. This is of course relative, in the same way that heights are not harmful if you do not fall from them. Adders have a venomous bite, and in certain circumstances this bite can prove dangerous. You should never attempt to pick up a snake you find in the wild, you will get much better views of it by remaining a respectful distance from it. And if you stumble upon one by chance, try to remain calm and back away gently, remember – the snake will be far more terrified than you by your sudden appearance. There, safety lecture over!

 
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Posted by on April 18, 2011 in Heathland, Reptiles

 

A Larval Landmark

This week is something of a watershed, marking the point at which the public events temporarily turn their back on terrestrial ecology and go in search of the sea.

Recent events locally have been full of interest and some of the most amazing wild finds of any year I can remember. The uncertainty of what an event will uncover is what gives my work a particularly exciting edge.

A larval landmark for me came a few weeks ago, when accompanying a group from the Exmouth Society on an evening walk around The Maer. The walk was billed as Exmouth’s hidden wildlife and we found a treasure which took everyone’s breath away: a caterpillar I have been waiting to find since I was a child.

The adult puss moth is a large grey furry beast, pretty amazing in itself, but its the caterpillar which is the real show-stopper. Lime green with a deep wine-coloured saddle, huge fake eye spots and bright red tail tendrils which can be hydraulically extended to put off would-be attackers, this caterpillar looks like something from a tropical rainforest. For such a garishly colour grub, it can be extremely hard to find in its tree.

We headed over to the small copse of trees on the Maer to look for the caterpillars, which is normally the kiss of death on finding any animal. Once you tell a group what you are looking for the wildlife has a habit of packing up and making itself scarce. After five minutes fruitless searching I was beginning to doubt if we would be lucky, when my colleague James stumbled upon it. James, being a thoroughly laid-back kind of chap, reached out to lean casually on a poplar branch while the group searched the leaves. He immediately realised his hand had closed over something plump and squidgy and on closer inspection realised he had literally put his finger on it.

The caterpillar was carefully handed round the group to admire closely and marvel at how this exotic could have gone unnoticed in the middle of town for so long! A perfectly local mystery.

More recently, Heath Week 2010 has been another resounding success. The annual festival launch day on Woodbury Common attracted more than 500 people through the course of the day, with both castle and estuary car parks filling up and meaning people had to drive onto the heath itself to park up. I led a morning heathland wildlife ramble, billed as 40 minutes but due to the sheer quantity of wildlife we found, this doubled to span a wonderful 80 minutes instead!

I ran a reptile ramble on Fire Beacon Hill Local Nature Reserve, which as ever pulled in a significant crowd. 56 people joined me on a trek up the hill from the Bowd Inn, to look for lizards, slow worms and adders… and we weren’t to be disappointed.

While the reptile sheets on site failed to provide their reptilian bounty, I managed to find the most colourful adder I’ve ever seen amongst the heather. As it was buried deep in the ling and bell heather I couldn’t trail the troop along to see it, but by the wonders of modern technology I managed to do shuttle runs with people’s digital cameras. The attached photo show the female in all her glory sunning herself in the heath. A vision in gold and straw; a sight which never fails to quicken my heart rate and sharpen my senses.

Next week sees the first in a number of beach days for me and a time when the heavy clumping boots are left in the car and the zip-off trousers are called into play! Wading about in East Devon’s rockpools is a rare joy and even a leaden sky is hard pushed to spoil the fun.

Monday, Wednesday and Thursday afternoons I will be located at Jacob’s Ladder beach in Sidmouth, to explore the rockpool creatures. I normally find at least one or two particular curiosities in the course of the summer rockpooling sessions, but the real treasures are uncovered by the holiday makers and local families, who bring their weird and wonderful discoveries to me for identification. Perfect, all the fun of rockpooling for me, with none of the effort! I don’t know why I continue to roll all those rocks?

Also this week, Fraser and I will be leading a walk with a difference on the Axe Estuary, on the super-low tide of Tuesday the 10th. Between 1pm and 3pm we will be guiding people between Seaton Marshes and Colyford Common Local Nature Reserves, without using a path or dry surface. No, instead we will be making like mud puppies and wading through the estuary silt for an entirely different perspective on the estuary. Places for this event are limited, and there is an age limit for the sake of safety, so for more information or to book places on this or any other EDDC event, please contact the Countryside Service on 01395 517557.

 
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Posted by on September 8, 2010 in Insects, Reptiles