Lakeland panoramas

I spend most of my time focussed in on the smallest inhabitants of lakes and streams, so I thought I would indulge myself in this post by looking at some grand panoramas in the region of the Lake District where I do most of my fieldwork.  I have often looked up at the hills that surround the lakes and rivers of the western Lake District as I worked but my schedule was usually such that there was not time to climb them, even when the weather smiled upon us.   A combination of fine weather and limitations on travel to more distant places gave us an opportunity to rectify this omission and we’ve climbed a few of the peaks surrounding Crummock Water and Ennerdale Water this summer.   The views that these provide offer a great opportunity to set our fine-scale activities into context.

This involved following the old drove road between Ennerdale and Crummock up as far as Floutern Gap, then following the boundary fence up the side of Great Borne (616 metres) which overlooks Ennerdale Water.  From here, we followed the ridge down and up to Starling Dodd (636 metres) then Red Pike (756 metres) and finally High Stile (806 metres).   The latter two peaks are on the watershed between Ennerdale and the Buttermere/Crummock valleys, affording spectacular views of five lakes (Derwent Water was just visible through a gap in the fells).   Further away, we could see the Solway Firth and the coast of Galloway to the north and, just on the eastern horizon, Cross Fell, the highest point on the Pennines, some 65 kilometres away.  

To the south we could see the River Liza flowing along the flat valley floor of Ennerdale, with Pillar and Scoat Fell rising up on the opposite side and, towards the eastern end, the imposing face of Great Gable, with Scafell Pike just behind.  Looking west, along Ennerdale Water, the high sides of the glacial valley give way abruptly (roughly between Angler’s Crag and Bowness Knott) to a softer landscape of improved pasture criss-crossed with dry stone walls.   This reflects a transition from hard volcanic rocks of the Borrowdale group which form the high fells to softer sandstones and mudstones.   

Buttermere, seen from Red Pike, September 2020.   The photograph at the top of the post shows Ennerdale Water from the same vantage point.

The scenery to the north was equally spectacular and its glacial origins even more obvious.   From the south-east end of Buttermere, the Honister Pass climbing up through a classic U-shaped valley.   There is almost no room for improved pasture on the floor of Buttermere, with the land rising even more steeply on the south side than it does on the north.  At the north-west end, however, there is an area of flat land where Mill Beck has deposited silt over the millenia, dividing the original glacial lake into two.  I remember that from O-level Geography as it was one of the examples we were expected to cite in an essay entitled “Lakes are temporary features of the landscape.  Discuss.”

The entire outline of Crummock Water was also visible, with Grasmoor rising up on the north-eastern flank and Mellbreak on the south-western side.   Grasmoor is the higher of the two peaks (852 metres) but Mellbreak is the more imposing, rising straight up from the lake almost as starkly as the Screes arise from Wastwater.   Wainwright lets his usually measured prose run away when describing Melbreak: “Melbreak is isolated, independent of other high ground, aloof.  Its one allegiance is to Crummock Water”.   I’ve seen it from all four sides over the past month or so, as well as climbing to the summit last week and, though it is not a particularly high peak (511 metres), it punches above its weight.  Forgive me for sharing a few of my photographs to underline Wainwright’s comments… 

Crummock Water from Red Pike, September 2020, guarded by Grasmoor on the right and Melbreak on the right.  Loweswater is just visible to the left of Melbreak.  
Melbreak from Grasmoor, on the other side of Crummock Water, August 2020.
Whiteside, Grasmoor and Melbreak, seen from the shore of Loweswater. 

Beyond Crummock Water we could see the outline of Loweswater, which is unique amongst Lake District lakes because its outflow flows towards, rather than away from, the centre of the Lake District.   Most of the Lake District’s lakes are deep, elongated affairs, formed in the valleys scoured out by glaciatian.  Loweswater, by contrast, is relatively shallow (maximum depth: 16 metres) and set amongst gentler terrain.  “Improved grassland” – enclosed fields where cattle and sheep graze – form almost a quarter of the catchment of Loweswater, compared to just 3 per cent of the catchment of Ennerdale, 2.3% of the catchment of Buttermere and 7.5% of the catchment of Crummock Water. Esthwaite Water, the most productive lake in the Lake District, by contrast, has improved grassland on about a third of its catchment area.   Not surprisingly, Loweswater has had some issues with eutrophication in the past.

Loweswater from the top of Melbreak, photographed a few days before the other pictures in this post, when conditions were more hazy.

And finally, Derwent Water was just visible through a gap in the hills and we could also make out the summits of Skiddaw, Blencathra and Catbells from our vantage points on High Stile and Red Pike.   We got a closer view of Derwent Water a couple of days later when we canoed from Portinscale near Keswick to St Herbert’s Island and back.   A few years back I found my way to the lake impeded by a film set and spent an enjoyable few minutes watching a scene from Swallows and Amazons being filmed.  Apparently, St Herbert’s Island appeared as Wild Cat Island in the film too and was also the fictional Owl Island in Beartrix Potter’s The Tale of Squirrel Nutkin.   Oh yes, and someone called William Wordsworth wrote a poem about it.   I wonder what became of him?

Skiddaw rising above the south end of Derwent Water, September 2020.
On location: filming Swallows and Amazons in Keswick, July 2015.

Some other highlights from this week:

Wrote this whilst listening to:  Shores, the new album by Fleet Foxes

Cultural highlights:  The Farewell, a 2019 film directed by Lulu Wang about a family trying to keep their grandmother from learning about her terminal cancer.  A very warm and humorous film despite the subject matter.   

Currently reading:  Where I Was From, a collection of essays about the history of California by Joan Didion.

Culinary highlight:  Homemade Battenburg cake, inspired by the efforts on the first week of Great British Bake Off.   

Blind to the obvious

I’ve moved just a few kilometres from the River Liza to the location for this post: Croasdale Beck, a stream which joins the River Ehen at Ennerdale Bridge.   Croasdale Beck has featured in a number of posts in the past (see, for example, “That’s funny …” and “Croasdale Beck in February”) partly because it continues to surprise me.   Maybe that reflects a level of complacency on my part: regular visits mean that I know what to expect which, in turn, means that I am alert to things that I do not expect.   Seeing something new in a stream I have never previously visited is evidence of life’s rich pattern; noticing something that was probably there on previous occasions but which I overlooked is a more profound and, somehow, humbling experience.  This post is about one of each of these sensations.

There are, for example, a number of turquoise-coloured boulders in the beck that were certainly not there when I first started visiting in about 2015.   Most of the stones in the beck are cobbles rather than boulders, so these stand out both for their size and colour.   The colour is, if you look closely, due to a thin surface film – a Cyanobacteria which I will call Lyngbya vandenberghenii although, because it is difficult to scrape off (the filaments live in amongst the rock crystals), and lacks any really eye-catching features, it is hard to be totally certain about this.   Presumably it likes the stability that boulders confer in this very flashy little stream.    I also see it in the River Ehen nearby but there its presence is easier to explain as it is confined to chunks of limestone washed in from the foundations of a section of the Coast-to-Coast walk.

Simulium argyreatum growing on a cyanobacteria-covered boulder from Croasdale Beck, Cumbria (shown in the photo at the top of the post).  The stone is about 30 cm across.   

Today, however, I’m interested in what is growing on top of the Lyngbya rather than in the Lyngbya itself: dense patches of what looks, with the naked eye, like small tan-coloured seeds.   These are the tiny larvae of Simulidae, whose adult phases are the annoying blackflies that swarm around streams on summer evenings.   They spin a web of silk on the substrate to which they anchor themselves using a ring of hooks at their posterior.   Their mouthparts include a pair of fans (one of which can be seen in the image below) and, by extending themselves above the stone, they can trap tiny particles (including algae) drifting in the current. They produce a secretion which makes the fans sticky and also have mandibles adapted to brush the trapped particles from the fans into their mouths.   Most descriptions of the Simulidae refer to this filter-feeding life-style but I’ve also seen them bent double so that their fans can brush up the algae which grow on the stone surfaces. 

Larvae of Simulum argyreatum on boulders in Croasdale Beck.  The upper photograph was taken in situ with the macro facility on my Olympus Tough camera (each is ~0.3 – 0.5 millimetres long) from a stone without the crust of Lyngbya whilst the lower photograph shows a magnified view of the feeding fan of one larva.

At some point, the larvae cease feeding and spin slipper-shaped cocoons with the closed end facing upstream and the open end downstream.   Six white ribbon-like gills protrude from the open end, ensuring a ready supply of oxygen to the pupa inside.   The adult develops inside this cocoon, eventually emerging with a duel raison d’être of having sex and irritating humans.  “Adult” hardly seems like the appropriate word: “perpetual teenager” seems more apt. 

Whilst the adult males feed on nectar, the females need a blood meal before mating, adding a dark Gothic twist to their natural history.  This difference arises from the roles each plays in reproduction: the male only needs the spurt of energy that the sugary nectar confers whilst the female needs the proteins and minerals from the blood in order to nourish the eggs.  In the south of England, bites from the Blandford Fly, a relative of the Simulium I watched in Croasdale Beck, can cause nasty rashes whilst in large parts of Africa the bites from other species of Simulium can inject the parasite responsible for Onchocerciasis, or river blindness.   This was a common disease in the region of Nigeria where we lived in the early 1990s so I’ve seen the damage that these flies can cause.   Much as we find black flies and midges to be a nuisance in this country, at least they are not vectors for potentially deadly diseases. 

At a deeper level, knowing about the life cycle of Simulium reminds us that we are not just observers of aquatic ecosystems, we are, indirectly, part of these ecosystems too.  We may like to think of ourselves as the ultimate predator (remembering that this power brings with it great responsibility) but sometimes, as here, we can be the prey too. 

Clusters of Simulium argyreatum pupae on the Lyngbya-covered surface of a boulder in Croasdale Beck.   Each is about 3-5 millimetres long. 

Reference

www.blackfly.org.uk

And thanks to Richard Chadd for identifying the Simulium from my photographs.

Some other highlights from this week:

Wrote this whilst listening to:  The late great Toots Hibbert, remembering, in particular, Toots and the Maytals’ set on the West Holt Stage on a glorious summer evening at Glastonbury 2010

Cultural highlights:  We’re in the Lake District this week and, having recently watched part of Simon Scharma’s BBC series on the Romantic Movement, I’m reflecting on the role that the landscapes around me played in catalysing the work of Wordsworth, Turner and others. 

Currently reading:  English Pastoral by James Rebanks, a thoughtful analysis of the state of British agriculture that does not shy away from criticism either of farmers or naïve ecologists.

Culinary highlight:  James Rebank’s thesis hangs on the necessity of animal husbandry to maintain healthy soils.  With that in mind, I ate a Lakeland lamb steak at the Shepherd’s Arms hotel in Ennerdale Bridge with a clear conscience. 

Sunbathing beside a Cumbrian stream …

Alfred Wainwright had little time for the Liza valley upstream of Ennerdale Water, commenting that “afforestation … has cloaked the lower slopes … in a dark and funereal shroud of foreign trees, an intrusion that nobody that knew Ennerdale of old can ever forgive, the former charm of the valley having been destroyed thereby”.  There are, nonetheless, still some spectacular views: the flat valley bed guarded by High Stile to the north and Pillar to the south (left and right in the photograph above) with Great Gable rising at the end of the valley (out of view in my photograph).   The Liza itself prowls across the valley floor, the channel changing frequently after storms.   The “foreign trees” that Wainwright so despised impart an Alpine character to the landscape looking upstream from our sampling site.   Maybe Wild Ennerdale will eventually replace these with some indigenous trees but, for now, the provenance of the terrestrial vegetation is of less interest to me than some green-brown patches on the submerged boulders in the river itself.

The River Liza looking upstream from close to our sampling site (NY 131 143).  The photograph at the top of the post shows the view up the Liza valley from a couple of hundred metres south of this position. 

I had been here two months earlier and these patches were present but far less extensive.  Now they covered the upper parts of several of the boulders on the left-hand side of the channel, sitting above patches that turned out to be a mix of green algae dominated by Bulbochaete.   Under the microscope these patches turned out to be the cyanobacterium Stigonema mamillosum – the most extensive growth of this elusive species that I have seen in this country and evidence, if any is needed, of the pristine condition of the River Liza.   

An underwater view of boulders in the River Liza, with olive-brown growths of Stignoema mamillosum on the top and green algae (mostly Bulbochaete sp.) on the sides.   The field of view is approximately one metre across.  

I wrote about Stigonema mamillosum after a trip to Norway in 2013 (see “More from the Atma River …”) and also in a couple of posts that used this organism to demonstrate some microscopical techniques (see “Now … with added depth of field” and “Stigonema in 3D”).  More recently, I have described it from Ennerdale Water, which the Liza feeds, and I’ve also seen it in Wastwater.  Never, however, have I seen it growing as prolifically as it grows here.   In all those places, it grows at or around water level and I could imagine that these submerged growths in the Liza would also be exposed at very low flows.  

Stigonema is one of a small number of cyanobacteria which exhibit true-branching, and also has filaments composed of two or more rows of cells.  The very large number of short lateral branches are characteristic and are the reason for the “mamillosum” part of the name (from Latin mamma meaning “breast” which, in turn, tells you more about the worldliness – or not – of Carl Adolph Agardh who originally described it).   These short branches will give rise to the hormogonia, short lengths of filaments which are released to enable the organism to spread.   Note, too, the thick brown-coloured sheaths around the filaments – offering protection from ultra violet radiation (see “Poking around amongst sheep droppings …”).  That’s a necessary feature for an organism that spends part of its life on an exposed granite boulder, even in Cumbrian summers.  

Stigonema mamillosum from the River Liza, Cumbria, August 2020.   Left and upper right images show the multiaxial filament with many short lateral branches whilst the lower right image shows the terminal end of the filament, where the multiaxial (i.e. several rows of cells) nature of the filament is obvious.  Scale bar: 20 micrometres (= 1/50th of a millimetre).  

Taken together, the multiaxial filaments, true branching and a capacity to live outside of water mean that Stigonema is one of the most advanced of the cyanobacteria.  It has, however, taken a long time to get here, reminding me of Graham Greene’s quote in The Third Man: “in Italy, for thirty years under the Borgias, they had warfare, terror, murder and bloodshed, but they produced Michelangelo, Leonardo da Vinci and the Renaissance. In Switzerland, they had brotherly love, they had five hundred years of democracy and peace – and what did that produce? The cuckoo clock.”   Cyanobacteria have had 2.4 billion years to evolve and what did they produce?  An ability to sunbathe on a warm rock beside a Cumbrian stream.  But who’s saying that’s a bad outcome?   

Some other highlights from this week:

Wrote this whilst listening to:  More BBC Proms: Sheku and Isata Kannah-Mason playing cello and piano duets and Laura Marling performing with the 12 Ensemble.  Plus, for nostalgia, Roxy Music’s Country Life from 1974 (old school vinyl version, complete with risqué cover) 

Cultural highlights:  The 2016 film Scully, about the “Miracle on the Hudson”, when an Airbus A320 made an emergency landing on water.

Currently reading:  The Incorrigible Optimists Club by Jean-Michel Guenassia.  

Culinary highlight:  (whispering quietly in case I blow my snowflake credentials completely) a rib-eye steak cooked in butter following a recipe on Samin Nosrat’s excellent podcast Home Cooking.   I only have a couple of steaks a year but, when I do, I want to make sure that they are worth the wait.

Belt and braces …

There was too much going on in the rock pools at Howick Bay to capture in a single post.  Just beyond the periwinkles quietly grazing on the turf of filamentous brown algae that I described in the previous post, for example, I photographed this vista.  In the foreground, there are buoyant ribbons of Ulva intestinalis (“gut weed”) rising above fields of the red algae Corallina officinailis, a red alga which deposits calcium carbonate in the cells to produce stiff, brittle fronds, unpalatable to most of the animals that share the habitat.   Then, in the background, there are fronds of the brown alga Fucus serratus (“serrated wrack”) which, in turn, bears massed filaments of yet another brown alga, possibly Pilayella – see “Epiphytes with epiphytes”).  That’s three distinct algal lineages in a single photograph. 

My observations of the biofilm sample I described in the previous post also revealed one other group: the Cyanobacteria and, more specifically, the Rivulariaceae.  We’ve met this family many times over the years (see “Both sides now” and references therein) and, whilst I knew that the family was also found in marine environments, I had not personally seen it before anywhere but in freshwaters.  The Rivulariaceae are “belt and braces” organisms, equipped with evolutionary adaptations to cope with both phosphorus and nitrogen deficiency.  This means that they are superbly equipped to cope with situations where nutrients are very scarce and, as a result, they can be particularly good indicators of the condition of the environment. 

Fragments of Rivulariacee colonies (probably Rivularia atra) from the biofilm at Howick Bay, Northumberland, August 2020.  20 micrometres (= 1/50th of a millimetre).  

Howick Bay is about 70 kilometres north of Newcastle and the River Tyne.  Travel a further 100 kilometres north and you reach another River Tyne.  This one is shorter, gathering water from the Lamermuir Hills south of Edinburgh and flowing east across East Lothian before joining the North Sea in a large sheltered bay just north of Dunbar.   I’ve never been there but when I worked at Durham University colleagues used to trek up regularly to study the algae on the upper part of the shore.   They had found colonies of Rivularia growing in pools on the beaches of this bay and were curious to know more about the conditions that allowed it to thrive.  

They noticed that the Rivularia colonies thrived in pools on the upper part of the intertidal zone but also that there were large amounts of seaweeds (especially oarweed – Laminaria digitata) dumped at the top of the intertidal zone during extreme high tides. As this rotted, phosphorus and nitrogen leak out.  Much of the nitrogen is lost to the atmosphere as ammonia but the phosphorus concentrations were often much higher.  This is where Rivularia’s “belt-and-braces” strategy comes into play: the pale green heterocysts at the base of the filaments (see “Blue skies and blue flowers in Upper Teesdale” for clearer illustrations) capture atmospheric nitrogen and turn it into compounds that the organism can use whilst the long tapering hairs exude enzymes which scavenge the phosphorus (still often bound into molecules originating in the seaweed.   

I did not see intact colonies of Rivularia at Howick Bay; however, its presence here is very plausible: particularly as the seawater here is relatively clean with few obvious sources of nutrients.   I suspect that the situation at Tyne Sands is an extreme manifestation of Rivulaira’s ability to efficiently recycle phosphorus from the communities around and about.  As soon as the naturally sparse nutrient pool is supplemented by other sources (i.e. “pollution”), it will be out-competed by faster-growing algae and, eventually, disappear.  So these few fragments of Rivularia (or a close relative) are a good sign that this part of the Northumberland coast is in a relatively healthy state.  So too, for that matter, is the diverse assemblage of seaweeds that we found during our brief visit.   

However, you don’t need to be a trained ecologist to work out that there is something special about the Northumberland coast.  The stream of people making their way to the beach at Dunstanburgh, our fellow walkers along the coast path and the denizens of the pubs and cafés in Crastor had all worked this out for themselves.   There is, in fact, a growing field of research on the subject of “blue space”, arguing that aquatic environments have a particular restorative potential.   Maybe – just maybe – dabbling around in rock pools awakens some primeval instincts of foraging for shellfish.   Or, maybe it is just reawakening memories of beach holidays as a child.  

References

Khoja, T.M., Livingstone, D. & Whitton, B.A. (1984).  Ecology of a marine Rivularia population.  Hydrobiologia 108: 65-73.

White, M., Smith, A. Humphryes, K., Pahl, S., Snelling, D., Depledge, M. (2010).  Blue space: the importance of water for preference, affect and restorativeness ratings of natural and built scenes.  Journal of Environmental Psychology 30: 482-493.

Yelloly, J.M. & Whitton, B.A. (1996).  Seasonal changes in ambient phosphate and phosphatase activities in the Cyanobacterium Rivulaira atra in intertidal pools at Tyne Sands, Scotland.  Hydrobiologia 325: 201-212. 

Some other highlights from this week:

Wrote this whilst listening to:  Sitar virtuoso Anouska Shankar’s concert at the BBC Proms, dedicated to her father Ravi.  

Cultural highlights:  The 2018 film Can You Ever Forgive Me? with Melissa McCarthy and Richard E. Grant.  We saw it when it first came out but it stood up well to a repeat viewing this week.

Currently reading:  A Shepherd’s Life by James Rebanks, a very readable account of farming in the Lake District.   Of particular interest to me as much of our fieldwork is in the area, watched by the Herdwick and Swaledale sheep that he writes about.

Culinary highlight:  vegan chocolate brownie at the end of Southend Pier which was, it occurred to me afterwards, the closest I have come this year to having a meal “abroad”