Lake Vyrnwy

Lake Vyrnwy

Lake Vyrnwy
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Lake Vyrnwy

  • Strange goings on

    This week there has been a few odd goings on. They have not been particularly rare occurrences but unusually for one reason or another. Probably the strangest find was an unusual singing Willow Warbler along the Yellow Trail. Generally it was singing like a typical Willow Warbler, but occasionally it would suddenly throw in a bit of ‘chiff-chaff’ song though quicker than a typical Chiffchaff. So why is it doing this? One option is that it could be a hybrid, however after a bit of googling it became apparent that it’s not uncommon for Willow Warblers to song mix or switch. A reason for this could be to deter any Chiffchaffs in the area from entering its territory, a few were heard in the vicinity.

    Unusual song of Willow Warbler (Recording by Gavin Chambers)

    Visually the bird looks like a Willow Warbler with long primary projection, pale legs and a strong supercilium (stripe above eye). It is perhaps a little paler, greyer than a typical Willow Warbler but as with all birds there is always going to be variation.

    Willow Warbler along Yellow Trail (Photo by Gavin Chambers)

    At the same time as watching the Willow Warbler a bat was spotted flying around over the river. It was around 5.30pm and the sun was out so it’s not really the time you expect to see a bat. Small swarms of insects above the river caught the bats attention and allowed for some photo attempts. Identifying bats inflight by sight alone is tricky and it had disappeared before the bat detector was retrieved. From its flight pattern/style, quick and erratic, and habitat it is likely to be a Common or Soprano Pipistrelle.

    Common or Soprano Pipistrelle over river (Photo by Gavin Chambers)

    A species that can be quite hard to see due to its skulking nature and camouflage plumage is the Common Snipe. Through the breeding season it is more often heard with its ‘chipping’ call, that sounds a bit like squeaky windscreen wipers, and also its fascinating ‘drumming’ display (see previous blog). Drumming is usually heard after dusk or around dawn, so when one was heard mid-morning it gave a great opportunity to see this dramatic display. You could see it spread its outer tail feathers and then swoop fast through the air to create the drumming sound.

    Robin nest in bottom right box (Photos by Gavin Chambers)

    The final bird oddity of the week relates to a very common and familiar bird, the Robin. While looking for gloves in our tool shed we came across a nest in one of the boxes, no eggs or adult present so we were initially unsure what had created it. However it soon became apparent that a Robin had taken up residence and was now sitting on 6 eggs. Nests are usually static creations but this one is very portable.

    Plant of the Week (by Gethin)

    Marsh Marigold / Cwpanau'r Brenin (Caltha palustris) (Photo by Gethin Elias)

    Hairless, perennial herb. Leaves are dark green and shiny, the lower ones long-stalked, cordate/kidney-shaped, up to 10 cm across. Upper leaves at stockless unclasped the whole stems. Large yellow flowers, 15-50mm across, have five petal-like sepals (no true petals) surrounding a mound of abundant anthers.
    Occurs in a range of wet habitats, usually in partial shade, such as the edges of rivers, streams, canals, lakes, ponds and ditches and then winter wet meadows and pastures.

    So it was rather a surprise to see it in a bog on open moorland at nearly 1600ft near Hafod. There were numerous plants in flower and they were all looking well.

    Previous Blog: What a Hoot!

  • What a Hoot!

    In the last couple of weeks our local ringer and volunteer has been out checking the ‘large’ nest boxes around the reserve. These large boxes are basically designed for the larger bird species like ducks and owls. At Lake Vyrnwy the usual species found in these boxes are Goosander, Stock Dove and Tawny Owl.

    Typical ‘large’ nest box with Stock Dove in entrance (Photo by Gavin Chambers)

    The location of these boxes is important when trying to encourage a certain species to use them. For Goosander they are ideally located over or near water (river or lake) with a clear flight path to the box entrance. Tawny Owl and Stock Dove are less fussy, they just want a convenient dry nest site to lay their eggs, though if the box is located deeper into woodland the Tawny Owl is more likely to be found in it.

    Female Goosander on nest (Photo by Mike Haigh)

    To find out the contents of the boxes a normal handheld digital camera is attached to a long pole, a timer set and then some quick manoeuvring to get camera through box entrance and positioned correctly before the timer goes off. A tricky task which Mike seems to have mastered (in general!) and a good way of saving time if the boxes are empty, plus it will often reduce disturbance to the birds.

    Adult Tawny Owl (top left) and 2 chicks with food cache (bottom left) (Photo by Mike Haigh)

    So the early results suggest a good breeding season so far, especially for owls. Of the boxes checked Tawny Owl have been in at least 10, Stock Dove in at least 6 and Barn Owl and Goosander nests have also been found. The Tawny Owl families have ranged from 1 to 4 chicks, with 4 being an unusually large brood for Tawny Owls. Being able to monitor Owl nests can give us valuable information as they are at the top of the food chain and can therefore can be a good indicator of environmental health, looks to be good with the number of owls being found!

    Our Intern, Ros, with a brood of Tawny Owls (Photo by Mike Haigh)

    One of the perks of the job, getting to see and hold cute balls of fluff!! They may look cute but their talons are not to be messed with, especially the adults. Unfortunately blood (of the human kind) is a common sight when dealing with owls which I saw first-hand last week, it looked sore!


    Plant of the Week – by Gethin


    Mountain Pansy / Fioled y Mynydd (Viola lutea) (Photo by Gethin Elias)

    Slender flowering stems, bearing usually one but sometimes as many as four blooms, are unbranched. Leaves are oval, lowdown on stems.

    Although the flowers of the Mountain pansy show the same kind of colour variations as the wild pansy, the two are not likely to be confused. The Mountain pansy, as name implies, shows a marked preference for upland homes, usually on lime-rich soils.

    At one time, garden pansies were forms of wild pansy bred and selected for size of flower and variety of colour. Today's garden pansies, however, were derived from a cross between the Wild and Mountain pansies and probably a third, foreign pansy. The Mountain pansy is the pure form and has always been a failure when planted in gardens. As long ago as the 16th century the herbalist John Gerard complained of the difficulties encountered in cultivating the mountain plant.

    The Mountain pansy grows well on the Dinas Mawddwy road.

    Previous Blog: Lets have a Chat

  • Lets have a Chat

    It has been quite a quiet week mainly due to the weather which has now become very wet as well as cold. The lake has certainly been topped up and is again overtopping the dam. However bank holiday Monday was a nice day and there was plenty to see around the reserve on my day off. A walk along the first section of the Red Trail (a lot of forestry work at the moment) produced singing Garden Warbler, Whitethroat, Tree Pipit and the briefest of reeling Grasshopper Warblers. There was also a flock of about 40 Crossbill flying around looking for food which they tended to head for Beech trees. As early breeders it was no surprise to see several juveniles amongst the flock.

    Female Crossbill along Red Trail (4th May – Gavin Chambers)

    Then to the Yellow and Blue Trails where pairs of Pied Flycatchers were guarding their nest box as they build their nests. Plenty of Willow Warblers and Chiffchaff around with a few singing Blackcap hiding in the shrubbery. Best of all was the sound of a Wood Warbler singing its wonderful trilling song, sadly a sound that is disappearing from some parts of the UK. At the top of the Blue Trail a flash of red indicates the Redstarts were about and a couple of Pied Wagtails looked like they wanted to find a nest site. No Goshawk this time but still a good route to take if hoping for one and looking for a good variety of bird species.

    Singing Wood Warbler around lake (4th May – Gavin Chambers)

    The uplands are a great place to see Chats. If you stop along the Dinas Mawddwy or Bala roads you are quite likely to see a Stonechat, Whinchat or Wheatear. Chats are showy birds, liking to sit on prominent perches like a fencepost or small sapling and all have a very similar ‘chat, chat’ alarm call which can be the first indication of their presence. A few Stonechat fledglings have been seen this week and given their recent dramatic decline after a couple of hard winters, 4/5 years ago, it is a good sign of a recovery, they may also have a second brood.

    Whinchat along Dinas Mawddwy road (9th May – Gavin Chambers).

    Other sightings have included a couple of adult Hobby over the moors on the 7th May, a pair of Mandarin have been seen a couple of times on the River Vyrnwy and just off the dam and there has been a trickle of hirundines (Swallows and Martins) and Swifts moving through the reserve with many feeding over the lake before moving on. The Otter has again been seen a couple of times at the top of the lake. I managed to miss it by a few minutes from the Centenary Hide today (9th) where a couple had just filmed it walk right in front of the hide!

    Plant of the Week

    Crowberry / Creiglys y Mynydd (Empetrum nigrum) (Photo by Gethin Elias).

    Grouse and other moorland birds feast on the black glossy fruits of the Crowberry when it ripens in late summer. The plant is also the main source of food for the caterpillars of several months.
    Crowberry flourishes in the uplands often alongside Heather, Cranberry and Bilberry. The edges of the shiny leaves curl down and inwards to form a narrow tube, a device that reduces the loss of water by evaporation through the pores on the leaf surface.
    I often hear people mixing Crowberry and Cowberry up. I remember them by the shape of the leaf, Crowberry is like a crows beak and Cowberry has a wide leaf like a cows tongue.

    Previous Blog: Gone a bit Cold!