Llanelli Naturalists Newsletter - June 1996
Andrew Lucas

Such were the number of interesting mammal records during this year in the county that the annual Carmarthenshire Bat Group report has had to be absorbed within a wider mammal review.  Hopefully this will set the pattern for future years, ensuring greater feedback to observers.

With only about 45 mammal species on the Carmarthenshire list, adding in new mammals to the county fauna is not easy.  Whist birdwatchers can hope for windblown vagrants, and the sheer number of plants and invertebrates means new species are constantly being discovered, the best hope for the mammalogist is one of the handful of vagrant European bats that occasionally cross the North Sea.  Yet in 1995 there was one, possibly two, additions to the county tally, whilst a third is making a comeback after a long absence.

Winter batwork continued with the exploration of underground sites.  Three Natterer’s bats were found at Cae Sarah (SN 752276) near Llangadog and the usual variety were recorded at the Mynydd Du cave complex.  Although no figures are available to the author, numbers are understood to have been low, a product of the remarkably mild winter weather in the first winter period.  Two greater horseshoe bats were present in the sea caves to the west of Pendine (SN 233078) on 21 April, an unusually late date for this species.

Away from the bats, the year started well with an otter being observed beside the Afon Lliedi near Old Castle Road in central Llanelli (SN 501001).  The recovery of the otter in the county over the last 20 years has been one of the most encouraging developments, and whilst other towns and cities in England make much of relatively common urban wildlife such as foxes and hedgehogs, it can be  a source of pride that we have what is a national rarity in our largest urban area.  Fortunately, this individual received a better reception that one seen in nearby High Street in 1905, which was apparently chased through the streets before being clubbed to death by the local populace!

A hedgehog found dead near Whitemill (SN 470216) began a dismal summer of road casualties, which included badger, grey squirrel, red squirrel, fox, hare, otter and polecat.  Whilst such records can be useful in monitoring population, the number and variety of species falling victim is most depressing.

By May, bat calls to licence holders were in full swing, in what was to prove a long hot summer for bat workers.  The warm weather made Pipistrelle colonies particularly noisy and, during June, calls peaked in the CCW office in Llandeilo at five a day.  Three hundred bats, almost certainly Pipistrelles, were reported from the Rhosnewydd estate at Tumble (SN 537123) on 5 May, and many calls followed as the colony moved from house to house.  On 15 May, 64 Noctules were counted at Morfa-bach,  Cydweli (SN 437070), a record for this site, and 170 Natterer bats were present at Derwydd Mansion (SN 613175) on the 22 May, also a record.  Brown long eared bats were recorded at Pilroath, Llansteffan (SN373136) where 10 were seen.  However, Cwrt Henri Primary School, which had been so successful in 1994, failed to live up to its promise when only 93 pipistrelles were counted on 12 June.

As the time available to members of the bat group is very limited, it was encouraging to see a trend toward householders counting their own bats.  Useful records included 75 pipistrelles at Trimsaran (SN 45-04-), 200 pipistrelles at Trap (SN 65-18-), 300 pipistrelles at Crwbin (SN 468132) and 180 pipistrelles at Laugharne (SN 274096) on 19 July.

A new record for the largest bat roost in the county was set on 3 July when 523 pipistrelles were counted emerging from Bryn Towy Mansion, Llangunnor (SN 433202) whilst, running a close second, 450 were recorded at Craig Ddu, Brechfa (SN 542303).  Emergence from the latter site had already started when observers arrived, so it is quite likely that the total is in excess of 500 bats.  The old trees associated with Dinefwr Park, Llandeilo (SN 61-22-) with numerous cavities also make ideal bat habitat.  At least 10 Daubenton’s bat, 5 whiskered/Brandt's bat and 1 Noctule were present on 17 July.  No doubt all these species breed in the park area, but where?

The red squirrel is now confined to the large conifer blocks in the north and north east of the county.  The ‘Sugar Loaf’, between Llandovery and Llanwrtyd remains the best place to see them, where one was reported on 14 July.  Sadly, a second on 3 September was found dead on the same stretch of road.  A third was brought in, killed by a cat near Rhandirmwyn Forest (SN 787438).  The animal was skinned with the skull sent to the National Museum of Wales - Cardiff.  The condition of the squirrel, and particularly its light weight, indicated that the animal was a youngster, which suggests a breeding population in the Rhandirmwyn area.

At the other end of the county, Llannon is well known for being an excellent area for dormice, where numerous copses and overgrown hedgerows provide ideal habitat.  A next box scheme run by Jan and Keith Crowden has been running in this area for three years, and their efforts finally paid off in 1995 when breeding was proved in two boxes (SN 555073) with a total of four in one and three in the other.

Roe deer were formally native to Wales, but became extinct by the 18th Century when the population was confined to northern Scotland.  Subsequently they have spread from southern England, where they were introduced in the last century.  Roes have been known from Brecknock for some time, but this year several were seen in forests in the north east of the county.  Considering the damage they cause to trees, the return of the roe deer may not be universally welcomed.  Another deer making inroads into Carmarthenshire is the  Muntjac.  An introduction from China, Muntjac are known from Brecknock and Pembrokeshire and, as a result, there are now increasing numbers of records from the north east and south west of Carmarthenshire.  An individual was seen near Llandeilo (SN 68-23-) in May, and no doubt the diminutive deer will become a regular feature of Carmarthenshire woodlands as colonisation continues.

Harvest mice have been a species long suspected in Carmarthenshire but never proved to occur.  They are known from both Glamorgan and Pembrokeshire, so it would seem that their absence could be dismissed as a product of under recording.  An appeal for information in local newspapers produced a reply from Kath Miller of Llandeilo, who gave a convincing description of a nest she found near Llandovery (SN 76-33-) in July-August 1968.  To date this is the only county record for this tiny rodent, but there will be an effort to trap more animals during the summer in 1996.

As harvest mice are known to occupy reedbeds (indeed this maybe their original habitat before forest clearance by man) a limited attempt was made to trap them in the first week of September at Ffrwd Fen (SN 418029) using plastic live traps mounted on poles 50cm above the ground, a design that has proved successful in East Anglia.  Unfortunately no harvest mice were caught but, amazingly, two dormice, one an adult and the other an immature were caught in stands of Phragmites , some 50cm from the nearest hedgerow, their usual habitat.  The occurrence of dormice in such habitats is not unprecedented, as they have also been found in similar habitat in south east England (Pat Morris, pers. comm.).  Does this represent post breeding dispersal, or do dormice make regular use of such habitats?

An otter was an unfortunate road casualty on 3 October at Manordeilo (SN 672202).  The second winter period of bat cave surveys started on 25 November with 2 greater horseshoe bats, 2 Daubenton’s and one Natterer’s bat at Greenbridge Cave, Pendine (SN 221092) and 5 greater horseshoe bats at Ogof Garreg Wen, Marros (SN 208094).  Counts at Mynydd Du on 3 December were disappointing with only 3 Daubenton’s, 4 Natterer’s and 8 Whiskered/Brandt's bats at Ogof Pasg.  Although the winter 1995/96 proved to be much harsher that those of recent years, mild weather in November had not encouraged bats to move to their winter quarters.

"Mammals in Carmarthenshire"

Work is continuing on the above book, which will document the status and history of mammals in the county, much in the style of the more common county avifaunas and floras.  Records are still required, especially older ones on species which have undergone change in the last 50 years, for example, red squirrel.  It is hoped to offer the book to members of the Llanelli Naturalists at a pre-publication reduced rate.  If you have any records, or know of other sources of information, please send them to the author at the address below:

Andrew Lucas,   Assistant District Officer, Countryside Council for Wales,

Changes in the Status of Carmarthenshire Dragonflies

I. K. Morgan

The publication, in 1985, of West Wales Dragonflies, containing detailed distribution maps with a brief but very informative text, by S. Coker & A.D. Fox was a milestone in the recording of Odonata in SW Wales. The text drew attention to the importance of seepage-rich pastures on the Preseli Mountains of Pembrokeshire for the Southern Damselfly Coenagrion mercuriale and announced newcomers to the Dyfed fauna (for example the Black-tailed Skimmer Orthetrum cancellatum) and the significant rediscovery of the Club-tailed Dragonfly Gomphus vulgatissimus on the Tywi.

As a decade has now passed since the appearance of the above text, it might be useful to summarise any changes noted in our knowledge of the distribution of Carmarthenshire's species since 1985. Most changes are, perhaps expectedly, due to an improved recording effort, as more previously-unvisited sites have been surveyed. For one or two species only, there appears to have been a genuine, if limited, expansion in range.

The Keeled Skimmer Orthetrum coerulescens would be a good example in the first, larger, category. For this species in Carmarthenshire, Coker & Fox could only offer a "few records", but it has been subsequently recorded from approaching a dozen or more stations - all being flush habitats, primarily in the uplands. An updated map of its known distribution is shown below, and it is anticipated that this species would ultimately (given time and recorder effort) prove to be widespread in the uplands where flushes and mires occur.

The rather capricious Scarce Blue-tailed Damselfly Ischnura pumilio is a nationally-scarce species. Coker & Fox (1985) mention its fondness for base-enriched flushes in Pembrokeshire but recent records from Carmarthenshire suggest that this is a species of peregrine habits, with a marked ability for dispersal in order to find new, often shallow water-bodies at an early successional stage, before such sites vegetate over and presumably become more favourable to other damselflies (Fox, 1987). Cham (1993), referring to a detailed study of this species in southern England, narrates how, "on warm, sunny days with little or no cloud cover, individuals of all age classes and sex were observed flying vertically upwards in a very direct and positive manner...[this]...continued until they were lost from sight, presumably then to be carried along by the prevailing winds".

Post-1985 localities for this species are given below:

  1. 2 were observed on a brackish grazing marsh near Commissioners' Bridge, Cydweli 22/408056 (20.7.1987).
  2. A female was swept from upper saltmarsh vegetation (with some freshwater seepages) at Morfa-bacas 21/542977 (16.6.1988).  Perhaps this individual dispersed from one of the populations on the commons of Gower?
  3. At least 12 were present on a recently expanded pond (on a peaty substrate) at Glyn Tai 22/610131 on 13th June 1988.
  4. Llandybie 22/619151 - one turned up on a garden pond (1988, G.W. Hopkins).
  5. One was noted over a water-filled deep ditch cut through peat at Carmel 22/589155 (Barry Stewart, June 1992).
  6. B.S. also noted "30-plus, including mating pairs" at a newly-excavated pond at the Wildfowl and Wetlands Trust Centre at Penclacwydd 21/530994 (20.6.1989).

Survey work in the last decade has confirmed the importance of the low-lying coastal belt of Carmarthenshire for the Hairy Dragonfly Brachytron pratense. A map of its currently-known distribution in the county is reproduced opposite

An enormous population occupies the ditch/fen complex around the Witchett Pool on Laugharne/Pendine Burrows ("MoD Pendine") (22/20, 22/30), and significant populations also occur in the Lower Gwendraeth Valley, where, for example, they can be observed hunting low down amongst emergent vegetation on the few open ditches or ponds at the Dyfed Wildlife Trust's Ffrwd Fen Nature Reserve (22/418023 and 22/418023) or on lengths of old canals in the Pembrey-Burry Port area. It also occurs on the low-lying coastal flats SE of Llanelli, though here it is absent from several badly polluted "pills" (ditches). In this area, Machynys Ponds 21/512980 is a good site, as is the clean, broad ditch which extends approximately westwards from the new Berwick Roundabout, south of Bynea 21/542987. Proposed new fen/water body creation schemes in the Llanelli area are likely to lead to an increase in populations of this rather specialised fenland dragonfly. There are inland records of one besides the Afon Tâf near Llanddowror 22/240152 (29.5.1991) and there is a seemingly strong population around ditches west of Cors Goch Llanllwch, near Cwmcoch 22/357187 (J. McCallum pers. comm.).

The Black Darter Sympetrum danae is a probably under-recorded (though still localised) species of acidic mires, often in the uplands. It flies late, normally from mid-July to early October. "New" localities for this species are: Cors Bryn Mawr (22/672501), A.P. Fowles (20.8.1987); Allt y Garn 22/587155 and Cors Carmel 22/594156 (both September 1991); "Cors Helyg" near Cefn Bryn Brain 22/740136 (August 1991); on seepages and pools on old spoil tips at Rhandirmwyn 22/782435, (late August 1993). A thriving population has also become established on ponds formed by the blocking up of ditches on the western end 22/366185 of the DWT's Cors Goch Llanllwch reserve near Carmarthen - the only lowland site for this species in the county. For the naturalist who prefers not having to trudge over the uplands or through difficult bog terrain to see this species, a late August or early September stroll along the new boardwalk at Llyn Llech Owain Country Park remains the best option (eg at 22/567150 or 569153). The present writer would, however, prefer if local enthusiasts would search out new sites!

The Southern Hawker Aeshna mixta was confirmed as a breeding species as early as 30th August 1979, when Owain D. Hughes discovered (and photographed) tenereal specimens at the Upper Trebeddrod Reservoir ("Furnace Pond") 22/50-02-. It was subsequently found (there being no work done on Odonata in Carmarthenshire. in the intervening period) during the mid-1980's at a number of coastal ponds such as Machynys Pond and Old Castle Pond (22/500004) at Llanelli and the "Ashpits Pond" (22/462012) just east of Burry Port. A. mixta is regarded as a probable breeder at WWT Penclacwydd (B. Stewart, pers. comm.). This late-flying hawker is also known to occur commonly at the Witchett Pool, 22/28-07-.

Ten years after the discovery of A. mixta in Carmarthenshire, the Black-tailed Skimmer Orthetrum cancellatum was added to the county list by Barry Stewart who confirmed breeding at WWT Penclacwydd by observing adults emerging from exuviae on 9th June 1989. It has subsequently been proven to breed at the main Machynys Pond 21/578990 and at Dafen Pond, Llanelli 22/531041 (both June 1989). As has been many times noted elsewhere, this species prefers ponds with bare margins and individuals often return repeatedly to the same "perch". The preference for unvegetated pond edges is noticeable at Machynys and Dafen and it is likely that other new water bodies in the Llanelli area  should prove attractive to this species. Indeed, it has already colonised "Penrhyngwyn Pond" 21/516974, presumably from populations already established at the nearby Machynys Ponds or WWT Penclacwydd, and has recently (1995) been recorded at Sandy Water Park, Llanelli 22/497004.

The Ruddy Darter Sympetrum sanguineum is believed to breed at WWT Penclacwydd (B. Stewart, pers. comm.) but is only sporadic at a couple of other coastal sites (such as the small, well-vegetated easternmost of the ponds at Machynys, 21/513979), and there is a 1995 record from Bevan's Pond on the Cydweli Flats (22/413046, A Lucas).  Perhaps it is overlooked, but the distinctive intense red of the males suggests not.

The Variable Damselfly Coenagrion pulchellum is likewise a rather enigmatic species in the county. It was recorded in 1984 by Coker (1985) from a pond at Ddôl 22/226233, and the present writer has taken specimens of Coenagrion with "wine-glass" markings on the second abdominal segment at the thickly-vegetated Typha-pond at Glynea, (Bynea, 21/553989) and also the small eastern Machynys Pond. J.R. Ellis very interestingly reports a capture of a singleton from the towpath at Ffrwd Fen 22/419028 on 13th June 1993. I suspect that this species is certainly overlooked, lost in "a sea" of the commoner blue damselflies (in particular Coenagrion puella). The impression of a slightly darker abdomen and the species' preference for really well-vegetated sites may be useful pointers to future detection. The low-lying coastal belt probably offers the best chance of discovery of C. pulchellum.

References

Cham, S.  (1993).   Further observations on generation time and maturation of I. pumilio with notes on the use of a mark-recaptive programme.  J. Br. Dragonfly Soc. .9, 40-46.

Coker, S. & Fox, A.D.  (1985).  West Wales Dragonflies.  Mountain Books, Haverfordwest.

Fox, A.D.  (1987).  Ischnura pumilio (Charpentier) in Wales: a preliminary review.  J. Br Dragonfly Soc. 3:32-36.