CORNISH RIVERS 1 : THE LYNHER IN SPRING

 THE LYNHER IN SPRING

Unlike the Tamar which runs from North to South, forming the boundary between Devon and Cornwall, most of Cornwall's rivers rise on Bodmin Moor and radiate from it in all directions in their short rush to the sea. 

The River Lynher rises on the north eastern side of the moor and in its 21 miles it runs from moorland, south -east through an ever-widening valley of small pastures and woodland and eventually forms a tidal creek which joins the Hamoaze, the main estuary of the River Tamar where it joins the sea beyond Plymouth Sound.

Map showing the course of the Lynher from its source on Bodmin Moor just north of the main trunk road  A30 into Cornwall, to to the complicated Tamar Estuary at Plymouth.

Near the source. We spent two days following and photographing the river from end to end  in mid-April '21. It is a cold late spring.This is close to the source, at Hendra, between Trewint of John Wesley fame, and Bolventor, immortalized in Daphne du Maurier's novel "Jamaica Inn."

 

Rising in a marshy depression the young river flows through wet 'willow carr', the trees draped with moss and lichen.

 

Running downstream

Clumps of Golden Saxifrage on the banks.

Although the moor was looking very sere and wintry still, we heard our first Willow Warbler singing its sweet clear cadence in these willows.

About a mile downstream the river is now running through small pastoral farms on the moor's edge. I was going to crop off these signs of abandoned rubbish but I couldn't resist making the point. Now especially, as all sorts of people are being blamed for the increasing tide of litter in the countryside but farmers never have the finger pointed at them for  their abandoned plastic containers and the ubiquitous black plastic wrap sheeting...... Undeterred, a Blackcap sang in the sunshine.

Ford crossing to another of the small farms. The land is cold, wet and heaven knows how these farms wrest a living from this unforgiving place. The next photo shows closer-up the little clapper bridge of great granite slabs.

The wet woodland here is mostly Alder carr. Each tree forms  at its foot, a higher little island of dryer ground where bluebells grow, and sometimes Early Purple Orchids.

Tony found old Otter spraint on this  squarish stone in the middle of the picture.It's distinctive musky but not unpleasant smell is surprisingly long-lasting.

Running south, now swollen by several other streams  the river skirts the eastern side of the moor in a widening valley.

The little lanes here are showing signs of spring now. as we come down off the moor.

Young fronds of Harts-tongue Fern are unfurling.

Sycamore leaves unfolding, delicate apricot at first.

Looking down at part of the pretty village of Berriowbridge from the first old  stone bridge over the river. Like all of these crossing places there was once a mill (which ran a saw) but only relics survive in buildings now derelict or converted to dwellings.

Looking downstream at Berriowbridge. On the left a fenced-off portion of the riverbank allows cattle to drink but not stray far into the water.

After over fifty years here, I had never spotted till now, the stone steps at the side of the bridge, leading down to a well. The villagers preferred this water to the mains supply till it became contaminated by development, I am told. They said  the well water tasted better.

Ivy-leaved Toadflax growing in the mortar of the bridge.

Downstream another couple of miles. The bridge at Bathpool. Tony has found Brown long-eared Bats roosting under the arches of this bridge in the past.

Brilliant male Grey Wagtail. These birds nest in the river banks and perch on river boulders, wagging their long tails.

As we go south the banks are swathed with Scurvy-grass. This isn't a grass but a member of the cress family, the leaves claimed to be rich in Vitamin C.

             Orange Tips are now quite widespread this spring.

 

 

 

 

 

 

 

 

 

 

  

Patches of Common Violet (not the perfumed Sweet Violet) growing on the lane banks with Greater Stitchwort and the first of the Bluebells.

Continuing downstream we come to Stara Bridge. The river has passed through an area of woodland, some of which is  a commercial coniferous planting, but managed as a Nature Reserve now.  Note the flood channel arch on the right. The Lynher is known as a 'spate river' which floods readily following significant rain in its upper catchment.

Carpets of Greater Woodrush grow in the wooded valley bottoms.

Wood Anemone.

Wood Sorrel.

Going over Stara Bridge. Note the triangular  refuge points for pedestrians to step into when traffic comes. The dark coniferous plantation is beyond and the flood channel arch can just be seen on the right.

These old, originally medieval bridges are these days having to be strengthened, and because they are narrow some of them are frequent victims of wide lorries.

Passing through a patchwork of valley bottom meadows and a tangle of woodland, the riverbank is maintained by various fishing clubs, restricting access in parts. The clear clean fast-flowing river with deep pools and shallow riffles is a favourite Salmon and Sea Trout water.

The handsome bridge at Rilla Mill. The mill here is gone too.It once powered a workshop for farm machinery.

Approaching the river again, at Bicton Mill, another converted mill.

But here we can see the remains of one of two water wheels .

I should imagine this is a fisherman's paradise in this tranquility.

Moschatel is a small, early-flowering plant growing in the shadier parts of the riverbank, quite a speciality of our Cornish river valleys. It disappears later in the season. The distinctive flower looks in five directions. Mum used to call it 'Town Hall Clock'.

One of the principal river crossings is at Callington New Bridge, on the main road from Tavistock through Gunnislake, Callington and on to Liskeard and Bodmin. It was originally a medieval turnpike and the toll cottage, rebuilt in the eighteen hundreds, has been derelict for several years but is now being restored extensively.

Situated at the bottom of the hill and with a sharp bend as soon as you cross, this bridge parapet is frequently knocked about by traffic misjudging the road! It's a good spot for Dipper watching, preferably from the bank below.

Just past the bend a narrow lane runs from the main road, straight up the hill. At the top is a granite marker stone saying 'Take Off' where an additional 'cock horse', hooked on at the bottom to help the coaches and carts to get up the steep hill , was unhitched again and returned to the stable down by the bridge.

Dipper.

Downstream an extensive area of old oak woodland is a very popular walking place, with a car park just below the New Bridge. There is an abundance of the invasive garden weed Variegated Yellow Archangel. Obviously the car park makes for easy  garden  chuck-outs!

A gingery Bumble Bee (The Common Carder Bee) is foraging for nectar.

Lady Fern unfolding. The delicate fronds are the first to die back in the autumn but conversely appear very early in the spring.

The wooded areas in the valley bottom are frequently  flooded and have seasonal pools  among the trees with flag iris and king cups.

The river downstream from Callington New Bridge runs along the base of a steep hill known as Cadsonbury. This is a National Trust holding with a large Iron Age hill fort on the top. This picture is looking east with Callington out of sight just to the east of the horizon. Looking down  from the bank of the earthwork, the area of dense woodland hides the river and the paths alongside it.

A mile or two further downstream is Pillaton Weir, with the sluice controlling a leat running to a mill further down the valley.

The main part of this once substantial weir is now broken down, presumably by repeated floods. Some forty or more years ago we watched salmon leaping the weir here.

Open rolling country with the river running through the valley south of Pillaton

Blackthorn is abundant in the hedges.

Looking downstream from the old Notter Bridge. The upper limit of the tidal water is here. The main A38 trunk road from Exeter to Penzance has been slightly re-routed and crosses the Lynher a little further away now on a modern substantial bridge.

These plaques are on the old Notter Bridge but I don't know what they represent.

Just below St Germans where the main tributary, the River Tiddy comes in from the left and joins the Lynher coming in under the railway viaduct. The river bends sharply to the east. This is about high water but extensive mud flats at low water attract wintering waders.

In the words of Dylan Thomas these were once 'heron-priested shores'

Since the 1980's Little Egrets have become frequent in our estuaries and now they seem to be commoner than Grey Herons, but perhaps that's just because they show up more and have a more active and visible feeding habit.

There is a good deal of arable farming here beside the estuary.

This pretty little Rue-leaved  Saxifrage is a bit of a SE Cornwall speciality. It flowers early in the spring then disappears. It grows on top of stone walls and other rubbly gravelly places.

There are only very small area of salt marsh in the estuary.

 

 

 

 

Near the end of the road, above Wearde Quay, looking towards the Hamoaze where the Lynher joins the main part of the Tamar estuary and it goes through Plymouth Sound to the sea.

The end of the road at Wearde Quay.

 In the space of two days, following the course of the river we also travelled from winter up on the moor at about 300 metres, to spring at almost sea-level at Wearde Quay.

Thanks to Jen & Pete Bousfield for information about some of the mills, and to Tony for chauffeuring and co-photographer. 

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Moth Trapping

 

 MOTH TRAPPING

Moths are so often  --  too often  --  considered to be the downside of butterflies. Butterflies are colourful, popular and attractive whilst moths are so often regarded as creatures of the night, those drab clothes-eating annoyances that flutter in your face when you are in bed on a summer night with the windows open.

Yes, they do fly at night, and are usually subtly coloured, but many species fly by day, are colourful and pretty. A very few small moths do eat clothes, but more eat old dusty decaying corpses so are some of nature’s recyclers. And yes, attracted by the bedroom light, they will come in, but sadly, far fewer these days as moths, like so much of our wildlife, are now in sad decline.

Not all moths are drab! This is a Garden Tiger.

 

 

 

Well-named Rosy Footman

 

 

 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

This lovely Blood-vein can be seen by day as well as being attracted to light.

Subtle colouring but still attractive: a Brindled Beauty.

 

 

 

 

 

 

 

 

 

A Mocha : what a pattern!

 

 

 

 

Trapping: When?

Moths can be trapped at any time of the year, but the low numbers in winter gradually build up in the spring, to reach peak numbers of both species and number of individuals, in July and August, then tailing off with the autumn fliers.

Trapping: How?

The most productive way of trapping is to make use of the little-understood fact that many (but not all) kinds of moths are attracted to light, so a trap consists of a light above a funnel which directs the moths down into a roomy container with egg boxes for them to creep away and hide and rest until they are released the next morning after they have been identified.

There are many kinds of trap. Various designs of traps and lights are available ready-made or the necessary components are readily available from specialist suppliers or can be made by anyone handy with carpentry and electrics although of course any doubt about things electrical should be put in the hands of an electrician.

Robinson trap set up in a garden. Egg trays for moths to roost in overnight are arranged in the black drum below the powerful 125Watt Mercury Vapour light. This design is considered to be the most efficient to retain the catch. Mercury Vapour lamps run hot so have to be protected from rain. The best light, but now discontinued. They can be powered by mains, battery or generator. These bulky traps are less portable than other systems.

Heath trap. Advantages are that it is collapsible, highly portable and runs off a battery powering a low wattage Actinic light (this is the blue light you see in shops' 'Insect Zappers') Like the Mercury Vapour lamp in the Robinson, it emits Ultra Violet light rays which are seen by moths.

Skinner Trap. This again is collapsible and portable, with a battery powering in this case, a 14Watt Synergetic tube. This has a different spectrum of Ultra Violet light and attracts well. The design of the Skinner does not retain moths quite as efficiently as a Robinson trap. Nevertheless when we use it in France where moths are still far more abundant than in Britain, we can catch well over 500 moths overnight. Quite enough to sort through next morning!

‘Moth-ers ‘ have their own favourite designs and lighting systems and there are all sorts of ingenious systems set up and with Facebook pages to cater for every aspect of catching moths. 

 

 

This home-made contraption, using a flat-collapsible laundry bag , with a little tweaking, ran well!

 Trapping: Where?

Traps can be set up permanently in one’s own garden, (with due regard for  avoiding bothering neighbours with a powerful light) but many ‘moth-ers’ travel to various habitats such as woodland, moorland, old meadows, areas of scrub. Experience guides the siting, but shelter, and avoidance of competing light need to be considered.

 

 

This Skinner trap is sited in the shelter of a hedge but also attracts moths from the hay meadow.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Robinson Trap with a Synergetic tube running in woodland.

 

Skinner Trap on the coast, north-west Wales. A specialist site but maybe attracting a migratory species.

 

A specialist site, a disused section of a cemetery, managed for wildlife. Children walking through on their way to school were fascinated to see the moths caught here.

 

The trap here was to attract specialist moths  whose caterpillars feed on pond-side emergent plants. The downside of these damp areas are the vast numbers of biting midges which are also attracted to the light!

 

Robinson trap with generator, run on Bodmin Moor, looking for moorland species. On this occasion a very strong wind got up and we had a minimal catch.When the trap is on the ground we put it on a sheet as it is easier to see the moths which are attracted to the light but quite content to roost on the ground nearby.

Normally a good site, on this particular night  a very wet mist came down and although the moths were attracted to the light as they flew nearer, they swerved away and avoided it. I wonder if the droplets of water in the air were defracting the light and disorientating them.

Trapping: Going back to When?

The time of year has already been referred to. Within that, the best, most productive conditions are overcast, mild, little moon, no wind. A little drizzle or light rain doesn’t seem to bother them; they will shelter from sharp showers and then re-emerge. I have found a really wet mist seems to disorientate them. They will fly but often seem to either miss, or avoid, the light. Full moon is said to compete and deter them but nature will break the rules as on occasions I have trapped on a full moon, with good catches. If bats appear, no doubt attracted by the moths, or if you have set the trap up near a roost, they quickly home in on a handy source of prey and the moths quickly detect the bats’ echo-sounding and disappear. 

It's best to choose a site with little or no competing light.

It is considered that it is bad practice to trap consistently, night after night, at the same site as the trap is bound to cause disruption to the moths’ feeding and breeding. A frequency of every third night or even less often, is advised.

Trapping: Why?

At a purely personal level, trapping appeals to the interest and curiosity of the 'moth-er', and all agree there is a sense of excitement every time the trap is opened as you never know what will be there. ‘Christmas every time!’ is the by-word!

Trapping is the main method of accumulating a substantial number of records  showing diversity of species, their abundance and distribution and trends will show up over the years.

Beyond that, and more importantly is the value of every record which gives

the species, the number of individuals of that species,

 where it was trapped,

when, and

by whom.

These records should be sent to the County Recorder, who will verify, validate the record and send it to the National Data-base. The records are evaluated, analyzed and provide information on distribution and population trends to inform conservation on a local and national level.

Within the past few years, the many hundreds of thousands of records of the larger moths throughout the whole country have been put into an Atlas:  "An Atlas of Britain & Ireland's Larger Moths", published last year and an invaluable guide to the status past and present of species and their distribution.

Identification

When in doubt the standard book is " A Field Guide to the Moths of Great Britain & Ireland" by Waring & Townsend.

If the small 'Micro Moths are a challenge the book to go to is "A Field Guide to the Micro Moths of Great Britain & Ireland" by  Sterling & Parsons.

Both of these handbooks are beautifully illustrated by Richard Lewington.

A photographic guide is "British Moths & Butterflies" by Chris Manley. This edition has been followed by a second which omits the butterflies but has more moths described with more but smaller photographs.

A good photograph with if possible something to show the size, can help when referring to someone more experienced for help with identification. The County Recorder will usually help. You can’t beat going out on a trapping evening with a group to get help and useful tips.

When opening the trap in the morning it helps to keep it out of the sun and to open up early while the moths are still sleepy from their ‘night in’. When they warm up they are off, and there is nothing more discouraging than to see your precious catch erupt out of the trap as you open up next day!

I will discuss other methods of catching moths and their other life-stages in a future blog.

 

Blogs I follow:

www..northcornwallnaturalist.blogspot.com 

www.musingsfromhigherdowngateandelsewhere.blogspot.com

www.downgatebatman.blogspot.com