Lake Vyrnwy

Lake Vyrnwy

Lake Vyrnwy
  Do you love our Lake Vyrnwy nature reserve? Share your thoughts with the community. Or if you're thinking about visiting and would like to find out more, ask away!  

Lake Vyrnwy

  • Rediscoveries

    The Lake Vyrnwy reserve is around 10,100 hectares in size which makes the finding and recording of certain species rather difficult, needle in a haystack at times. Given the size, conducting comprehensive surveys of the whole site would be extremely time consuming and therefore surveys of specific habitats or areas are more realistic. The other method for recording species is Ad-hoc, which is basically coming across species while out and about, either specifically looking for certain taxa or randomly wandering.

    Gethin trying to be artistic with my camera! (Photo by Gavin Chambers)

    Last weekend Gethin and I (Assistant Wardens) went wandering around areas on the reserve we hadn’t explored much before and where some old records of interesting plant species occurred. The first location was a steep rocky heather clad slope which we had not explored before. A lesser clubmoss, not recorded on the reserve for several years, was the highlight along with banks of bilberry ladened in large juicy berries to keep us well fed!

    Lesser clubmoss - less than 5cm tall (Photo by Gavin Chambers)

    Our next aim was to go looking for some old records within the boggier areas of the reserve, with sedges being the point of interest. However the first plant to find was somewhere along a stream on a rock, which after a short wander we found it – mountain everlasting (Antennaria dioica). Only a couple of sites in the county of this species which has male and female flowers on separate plants (dioica meaning ‘separate’).

    Mountain everlasting - no flower stalks seen (Photo by Gavin Chambers)

    It was then time to start wading into almost wellington deep bogs to look for interesting sedges. Fortunately Gethin knows what he is looking at when it comes to sedges so it wasn’t long until we (I mean Gethin) found Carex limosa (bog sedge) with its distinct drooping seed heads and soon after several clumps of Carex paniculata (greater tussock sedge). The final sedge was Carex magellanica (tall bog sedge), which to me just looked like Carex limosa but Gethin reliably informed me that it was different… I’ll let you decide!

    Carex magellanica (left) & Carex limosa (right) (Photos by Gavin Chambers)

    Previous Blog: Lake Fernwy

  • Lake Fernwy

    In our recent RSPB magazine, Natures Home, it stated that 16,000 species have been found on RSPB reserves across the UK. It then breaks it down to the top 10 reserves and also the reserve with the most species of a certain taxonomic group (birds, dragonflies etc.). Lake Vyrnwy turns out to be the RSPB reserve with the most ferns, with 22 species, which I immediately saw as a challenge!

    Given my limited knowledge of ferns I thought it would be a good summer/autumn project to learn how to identify ferns while at the same time trying to find as many of the 22 species as I could. There are only 64 species found in the UK with many of these being fairly distinct which meant I could get off to a quick start without too much head scratching.

    Probably the easiest species, which I would suspect the majority of you reading this will have already seen, is bracken. To be honest it hadn’t crossed my mind that it was a fern but having now studied all ferns it quite clearly exhibits fern characteristics.

    Wall rue (left) and maidenhair spleenwort (right) on office wall - by Gavin Chambers

    Old mortared walls are a good place to look for ferns with a few limestone species liking the lime mortar. Around the shop/office I found maidenhair spleenwort, wall rue, and hart’s tongue. The local graveyard wall has in the past been known for its ferns and from what I have found it still is, with some nice species such as: rustyback, black spleenwort and brittle bladder fern (my latest find). Another rocky species, though not requiring limestone, is the parsley fern which as its name suggests looks a little bit like parsley.

    Parsley fern likes rocky screes - by Gavin Chambers

    Identification gets a little trickier when looking at woodland species, especially the ‘shuttlecock-shaped’ species. So far I have identified male, lady, broad-buckler and lemon-scented fern along with the scaly male fern, but this is split into three species which I am yet to fully understand. Other woodland species found are beech, oak and hard fern as well as common polypody which is often found growing on tree branches and trunks.

    Lemon-scented fern which has a citrus smell when young - by Gavin Chambers

    Perhaps the trickiest species that I have found is the wilson’s filmy fern which is one of the smallest ferns and grows over damp rock, often in the splash zone of running water. Fortunately I had a rough idea where it had been found and after a couple of visits to the area found three rock faces which had it growing. It wasn’t at its best given the recent drought but it was good to see it was still present.

    Wilson's filmy fern, curled up due to dryness - by Gavin Chambers

    So I have currently found 18 of the 22 species on the reserve in around 2 months of searching. Two of the four remaining ferns are tricky to separate and will require more studying and a third species, the narrow-buckler fern, I may have found but it hasn’t completely unfurled yet so will have to go back for another look.

    Previous Blog: Mimics and Migrants

  • Mimics and Migrants

    In the last month we have enjoyed some nice warm sunny weather which has given the many invertebrates, from moths to hoverflies, a chance to emerge and not forgetting the midges! This has been great for the breeding birds as they relentlessly forage for food for their hungry chicks including the newly fledged pied wagtail chicks outside the volunteer accommodation.

    Pied wagtail chicks waiting to be fed outside volunteer accommodation – by Gavin Chambers

    Given invertebrates are the prey item for so many predators, such as birds and other invertebrates, some have come up with ways of reducing their chance becoming breakfast. The hoverfly volucella bombylans (photo below) is one of the better mimics which looks a lot like bumblebee species, and amazingly has more than one colour form as shown in photo below. Incredibly this species lays its eggs in the nest of bumblebees which makes you wonder if the bumblebees themselves are fooled by the mimicry? However, it is generally thought that mimics look like bumblebees and/or wasps to make them look noxious (i.e. distasteful and likely to have a sting) to put predators off eating them.

    Volucella bombylans (hoverfly) at Lake Vyrnwy – by Gavin Chambers

    Moths are also good at mimicry to try and avoid predation. In general they use camouflage to blend into their typical habitat such as the buff-tip which looks a lot like a birch twig. Others will use bold flashes of colour to warn off predators with a few species having the larges ‘eyes’ as seen on the peacock butterfly.

    Buff-tip – by Gavin Chambers

    Despite their size invertebrates can travel very long distances, using weather systems to blow them to a new location. Species such as the painted lady butterfly and humming-bird hawk-moth are well known for their movements from Africa and the Mediterranean. However, this year has seen a mass movement of a tiny moth, plutella xylostella (diamond-back moth), with a wingspan of only 15mm. It is thought that millions have arrived from Continental Europe though we have only had a maximum of 7 in the moth trap.

    Plutella xylostella (Diamond-back moth) – Archive photo by Gavin Chambers


    Previous blog: Bank Holiday Stroll