LLANGLOFFAN FEN NNR.
One evening last week I was to be found lying flat-out in a bog, oblivious to everything but the small iridescent blue damselfly clinging to a wind-blown grass stem a metre in front of my lens. Patience was required as the breeze that had got up as the sun hid briefly behind clouds was making close-up photography difficult and the damselfly was unsettled both by my movement as I edged closer and the forest of vegetation waving around it. I had dropped in on Llangloffan Fen, a National Nature Reserve owned and managed by the Wildlife Trust of South & West Wales, on my way back home from a day with the Pembrokeshire Federation of Angling Coaches coaching school children in the art of angling, and I was keen to see how the Reserve and its wild inhabitants were coping with the long dry spell.
Llangloffan Fen is a 41 acre Reserve in the upper reaches of the River Western Cleddau between Mathry and Castle Morris and comprises the western end of the largest remaining floodplain river valley mire surviving in Pembrokeshire. The eastern end of the NNR situated downstream of Llangloffan bridge is managed by Natural Resources Wales. The site is 60 metres above sea level and although it once drained northwards to the sea at Aber Mawr, modification by glacial melt water after the last ice age and blocking by glacial deposits changed the direction of flow, leaving a small watercourse, the Western Cleddau, meandering eastward and south through flat waterlogged ground as it is today. The young river joins an eastern arm flowing south from Scleddau at Heathfield and then continues via Welsh Hook, Wolfs Castle, the Treffgarne Gorge and Haverfordwest before joining the Eastern Cleddau at Picton Point and flowing out to sea through the Milford Haven. The area supports tall fen, wet heath and carr communities and associated species and there is also an area of semi-improved pasture. The Reserve has been enhanced by the creation of a few small ponds and improvements continue to be made by the Wildlife Trust to improve the biodiversity.
PART OF THE RESERVE SHOWING BOTH FEN AND CARR VEGETATION
Having parked the car in the visitors’ car park, I had gone through the gate and set off leftwards on the circular walk that allows visitors to access the otherwise inaccessible wilder areas of the Reserve. One of the first things that I saw nestled in tall vegetation was the first of the ponds, but it was much decreased in size since I last saw it a few weeks earlier. The hot, dry weather that we have been enjoying recently has lowered the level of the pond, thereby reducing both its depth and its surface area and I wondered how this might have impacted on the aquatic wildlife that was usually present. All seemed still as I approached the pond, but it soon became apparent that the surrounding vegetation was still buzzing with life as birds called from nearby bushes and insects of many types fluttered, crawled and hopped through the stems and leaves.
There was no sign of the froglets and toadlets that had been in abundance earlier in the year around the margins of the pond or any of the newts that I believe are to be found in the pond. The level was so low that it is likely that, if anything were still in the water, any passing predator would find it easily and make a meal of it. Indeed there were large bird footprints in the mud at the water’s edge – probably a prospecting heron. The hope is that the young amphibians have found safe refuge in the surrounding countryside and are finding enough food to survive and grow on so that they can return to the pond early next year to continue the cycle of life.
In the depths of a previous winter I have found the remains of a teal by this pond, the left overs from an otter’s meal. There were no signs of otters or ducks by the pond on this occasion, although undoubtedly they will be passing by from time to time particularly when the frogs return in the late Winter / early Spring.
ONE OF THE SMALL PONDS THAT HAVE BEEN CREATED ON THE RESERVE
Among the birds I could identify calling on this occasion were whitethroat, wren, linnet, goldfinch and dunnock, but these were largely invisible, escaping the heat of the day by skulking in the depths of the leaf cover and rarely showing themselves. Fortunately, the insects were far more amenable and a number of different species of butterfly and a few day flying moths were busy flitting from flower to flower to sip the nectar and at the same time carry out the essential job of pollination. The butterflies included Large Whites, Small Tortoiseshells, Red Admirals, Ringlets and Small Skippers, the latter so named for their habit of ‘skipping’ from flower to flower with short and erratic flights. Ringlets have been studied by a number of lepidopterists and geneticists who have been interested to know whether the variation in the number of spots (rings) on the wings between individuals has a genetic or an environmental explanation, or whether it is just a random feature. The truth is still unclear but it appears that there is no discernible reason for the variation and it is probably random!
RINGLET BUTTERFLIES WERE NUMEROUS NEAR THE POND
ONE OF A FEW SMALL SKIPPER BUTTERFLIES IN THE AREA
Amongst the numerous day flying moths, easily the most striking were the metallic green and red-spotted Burnets. These were the 5-spot species, a lover of damp meadows, as opposed to the 6-spot Burnet that favours drier terrain. The Burnet larvae feed on greater bird’s foot trefoil before spinning a white paper-like pupal case on a grass stem for the development of the adult. I saw several of these on the Reserve but all were empty. I was unable to identify many other moth species as these are outside my area of expertise, but I did disturb an Orange Underwing from leaf litter near a gorse bush and watched it flash its orange signals as it disappeared into the darker interior.
A STRIKING 5-SPOT BURNET MOTH PHOTOGRAPHED ON THE DAY
Sadly, it was too late in the year to see an adult Emperor Moth, a spectacular large moth that, if one is very fortunate, can be seen on the Reserve during April and May. I have previously found their attractive green, yellow and black caterpillars at Llangloffan but I have only seen an adult once and that was at a distance. The distinctive ‘eye spots’ on the adults’ fore and hind wings are an impressive feature that is believed to be a defence mechanism against predators who think that the moth is the facial disc of a larger animal.
CATERPILLAR OF THE EMPEROR MOTH FOUND DURING A PREVIOUS VISIT
Everywhere I looked when I crouched down to be near their level there were animals of bewildering diversity busily engaged in what they do so well – getting on with their complex and unique lives in as effective way as they know how. Flies, bugs, beetles, spiders, ants, bees – all life was there! Whether they are feeding or looking for food, mating or looking for mates, exploring, resting or avoiding enemies, all their energies are focused on ensuring their own survival and passing their genes on to future generations.
Amongst the most active of these animals were various species of hover (or flower) flies indulging in their dazzling aeronautical ability to hover motionless in the air one minute and then whizz off with tremendous speed and accuracy the next to land on a chosen flower head to feed on nectar and pollen. I noticed one species in particular, that I later identified as Eristalis horticola, regularly visiting the pond to land on the surface and thought initially that they might be drinking, only later remembering that this was a species that laid its eggs in still or stagnant water. Its larvae develop into the so-called rat tailed maggots that live in the water and breathe just below the surface through a telescopic breathing tube at their rear ends.
Eristalis horticola – A SPECIES OF HOVER OR FLOWER FLY
Bees were also plentiful, particularly various species of many peoples’ favourites, the bumble bee. I was able to identify Red-Tailed and Buff-Tailed Bumble Bees but no Honey Bees and the others avoided positive ID – genning up on bee identification is a ‘must do’ for me this summer! Having just read Dave Goulson’s fascinating and entertaining book ‘A Sting in the Tail’ on Bumble Bees and other insects, I am now fired up by these wonderful creatures, their complex life styles and the challenges that they currently face. If you haven’t read this book I would urge you to do so. You will never see bees in the same light again!
As I concentrated on what was left of the shrinking pond, all initially appeared to be quiet, but suddenly as if from nowhere a missile shot across the surface with a rustle of wings and a flash of electric blue. From its size and colour I judged it to be an Emperor Dragonfly but it was too fast and stayed too short a time for certainty and I could just stare after it in wonder as it disappeared into the distance to find different air space to hawk for its prey. A large dragonfly on the wing is an impressive sight with its ability to hover, dart, change direction and even fly backwards with enormous speed and agility. Dragonflies were amongst the first winged creatures on the evolutionary ladder, first appearing in the late Carboniferous about 300 million years ago, and some grew to large size having a wingspread of 2 feet and more. The passing of the dragonfly over the pond seemed to create a wave of activity and I quickly became aware of stirrings in the pond side vegetation as jewel like damselflies took to the air to land again on a different stem or leaf. At the far end of the pond a pair of medium-sized, blue-grey bodied dragonflies, probably Broad Bodied Chasers, appropriately played a game of chase, but, by the time I reached them, their game had taken them to pastures new. More obliging were the numerous damselflies that were fluttering from leaf to stem along the water’s edge and resting on the vegetation surrounding the pond.
FEMALE EMERALD DAMSELFLY – Lestes sponsa
A MALE EMERALD DAMSELFLY ON A STEM
Patience and a stealthy approach enabled me to get within photographic range of a number of individuals and pairs and to marvel at their delicate beauty as they sparkled in the sunshine. Two species seemed to predominate, the Common Blue Damselfly and the Blue Tailed Damselfly with an electric blue segment near the end of its abdomen. As positive identification between the Common Blue and the very similar Azure Damselfly, which is also present on the Reserve, is difficult without close inspection, both these species might have been present while I was there.
A BLUE-TAILED DAMSELFLY (WITH A PHOTOBOMBING SMALL BUG!
MALE AND FEMALE COMMON BLUE DAMSELFLY PAIRING
Mating in dragonflies and damselflies is a complicated procedure involving display flights ending in the male gripping the female with his anal appendages by the back of the head and the female bending her abdomen forwards to bring her genital opening up to the male’s copulatory organs on his second segment to form a ‘wheel’ or ‘heart’ shape. A packet of sperm is then transferred following which the female lays the fertilised eggs in a suitable water body. Whilst this might appear to be too much information for some, it is a fascinating process with the ‘locking’ mechanisms employed being species-specific thereby preventing intra-specific mating attempts.
COMMON BLUE DAMSELFLIES MATING
On a closer look at the bases of some of the reeds emerging from the water I became aware of a number of brown, dried husks, attached and motionless. These were the shed carapaces of dragonfly and damselfly larvae that had climbed up them on completion of the aquatic phase of their growth and development. Growing larvae live in freshwater for months or years feeding on a range of prey species and shedding their skins (moulting) periodically as they grow until they are ready to undergo the final transformation. The adults that had emerged from them were the ones that I saw now flying about and ensuring the continuation of their species.
THE SHED LARVAL ‘SKIN’ OF AN EMERGED DRAGONFLY
On leaving the pond and its bustling life I continued along the circular path to a section of boardwalk that I had seen being replaced a few weeks before when I had been at the Reserve to assist some fellow volunteers to plant a new hedgerow along a section of the boundary. I was delighted to see that all the young saplings that we had lovingly rooted into their new homes were surviving and looking healthy. The replaced section of boardwalk stood out stark and bright against the surrounding area but it was strong, safe and welcoming and it will not be long before its colour mellows and it sits more comfortably back into the landscape. The Wildlife Trust, particularly through its Wildlife Trust Officer for Pembrokeshire, Nathan Walton, works very hard and successfully to manage the many local Reserves in its care for the benefit of wildlife and people despite operating with limited resources, and the use of volunteers to help with this management is an important way of increasing the amount of vital work that can be achieved. They are always looking for new recruits and I can heartily recommend it as an enjoyable and valuable activity. Nathan would be delighted to hear from you!
A NEW SECTION OF BOARDWALK ON THE RESERVE
During my circumnavigation of the Reserve path I couldn’t help but be aware of the wild and natural abundance of life, both plants and animals, within the Reserve and the strong contrast with the reduced variety of the life outside its boundary. Yes, there were a large number of sheep in some of the surrounding fields and the odd crow, magpie or gull occasionally landed there, but otherwise it was like a brown desert, devoid of life and variety. The remains of the ‘improved’ grassland on which the sheep attempted to graze was of little or no environmental value and would have shown very limited biodiversity. On the other side of the Reserve, fields of arable crops took over, but here again it was an environment of monoculture that would have been sprayed repeatedly over previous months to kill off whatever plant or insect dared to invade it. The only spaces left as habitats for wildlife are the occasional thin hedge or small isolated copse of trees, like islands in a waving ocean.
THE POOR HABITAT PROVIDED BY THE SHEEP FIELD
OUTSIDE THE RESERVE BOUNDARY IS OBVIOUS
THE CONTRAST BETWEEN THE RICH VEGETATION
WITHIN THE RESERVE AND THE MONOCULTURE BEYOND IS MARKED
Evidence for the adverse impact of intensive agriculture on the natural environment of Pembrokeshire is strong and undeniable and knowledge of the true situation would come as a shock to many who cannot see beyond the attraction of fields full of skipping lambs, waving barley and green grass. Over 80% of the Pembrokeshire countryside is recorded as being at the lowest level of biodiversity and many of the County’s rivers and streams are fishless or with seriously depleted fish and invertebrate populations. Thank goodness for roadside verges and the Council’s policy of not spraying and not cutting before the main flowering season is over. Without these flower filled verges and the other protected wild areas there would be scant few sources of nectar and pollen for insects and therefore our insect populations would be in an even worse situation than they already are.
A JUVENILE SEDGE WARBLER NEAR THE HIDE AT LLANGLOFFAN FEN
Above and below are images that I have taken during previous visits to Llangloffan that demonstrate the richness of the biodiversity on the Reserve. If the wildness of the Reserve had not been preserved and managed for wildlife, these wonderful animals and plants and many like them would not be present in the area. Otters, polecats, hedgehogs, stoats, badgers and foxes are known to regularly visit the Reserve but because it is in isolation, they have to travel through the inhospitable surrounding landscape in order to reach pastures new and prospect for mates. An otter was found dead on the road passing by the Reserve earlier in the year; a casualty of the traffic that rushes past day and night without a thought for what else might be sharing the road.
YOUNG GRASS SNAKE AT LLANGLOFFAN
FEMALE MALLARD ON THE HIDE POND
Whilst the presence of Reserves like Llangloffan are vital as reservoirs for wildlife they are under constant threat and wildlife needs more than small pockets of habitat to flourish. The future facing the Pembrokeshire landscape and its wildlife is in the balance and this is exacerbated by the onset of Brexit with all its implications for the changed management of intensive agriculture and other threats. I will be exploring the challenges, threats and opportunities on this subject and the direction that the Welsh and UK Governments appear to be taking in future Pembrokeshire On-Line articles. It is a developing situation that should be of concern to all people living in the County and beyond, and that includes the agricultural industry which currently is paying little regard to the long-term health of its prime asset, the land on which it operates. We all stand to lose if the situation is allowed to continue. Watch this space!
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Please note that all photographs are Copyright protected. Prints in various sizes of any photographs used in the articles can be obtained by contacting the Author.
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David Gardner, Environmentalist and Photographer