Week 4
This is a long one, so please be prepared, as the topic is serious. I have broken the text halfway, so that you can recharge your batteries and return refreshed. With that, let’s get started...
Part 1
At first sight
The overwhelming feature of Tarn Hows is its beauty. There is no escaping it. The moment I arrived and walked the short distance from the National Trust car park to the tarn itself, I realised I was somewhere special. A chocolate box description does not do it justice. Tarn Hows is far more scenic than that and explains why more than half-a-million people visit it each year[i].
For linguists, the word “tarn” derives from the Old Norse word tjörn, literally a small mountain lake without tributaries[ii]. Officially a tarn should have a glacial origin but in Lakeland the word has come to refer to any stretch of water that is smaller than a lake and larger than a pond. The definition of lake or pond is wide open to disagreement, as is the use of the word tarn.
There is a short and easy walk around the tarn itself, all of 3.2 kms (1.8 miles), with a compacted surface to the track that is suited to most things, wheelchairs included[iii]. To complete the walk without stopping was for me impossible as around each corner, and there are plenty, is something different to photograph, inspect or discuss. Cumbrians love to chat, as do I, so I did plenty of stopping, and at one point even heard Cumbrian spoken. During my time in the Lake District, I have not done too well with Cumbrian, actually the Cumberland dialect[iv], as it is a tongue that is in steep decline[v].
Environmental and historical significance
Beauty apart, there is an undercurrent at Tarn Hows that most fail to appreciate. It is not that the place may be haunted[vi], it is, but that evidence of climate change is all around. What is more, Tarn Hows is sadly artificial. It did not achieve its current state by chance. It is thanks to the hard work of mankind that we enjoy the place today.
Until 1862, much of the Tarn Hows area was common grazing land but that year, thanks to the Inclosure Acts[vii] (1602-1914), one James Marshall (1802-1873) acquired Tarn Hows and brought it in to the larger 4000-acre Monk Coniston estate. At that time there were three tarns, Low Tarn, Middle Tarn, and High Tarn. John Marshall constructed a dam at Low Tarn, which converted the three smaller tarns to the single, larger one seen today.
Marshall’s vision for the landscape at Tarn Hows involved clumps of deciduous trees - sycamore, beech, alder, cherry, willow - planted to highlight the many rocky knolls and the dramatic landscape beyond. To protect his new planting of broadleaf trees Marshall also planted nurse crops of conifers, including larch and spruce. These were intended to protect the young broadleaf saplings from the harsh winter weather and would be removed once the broadleaf trees were established. However, Marshall died before his vision was realised and the nurse crops were never removed[viii]. It is why larch and spruce trees now dominate the modern Tarn Hows panorama. They were never Marshall’s intention.
By 1899 Tarn Hows had become an important beauty spot and was then described by one Henry Swainson Cowper as:
"Tarn Hows, beloved by skaters in winter and picnic parties in summer. Here comes every day at least one charabanc load of sightseers from Ambleside or Windermere[ix]."
Before reaching the tarn itself, I sat for a moment on a grassy knoll, surveying what lay below me. There was not a single ice skater to see, I guessed thanks to climate change, as the environment rapidly warms. There was some ice, as this was January, but just a sliver near the tarn’s eastern shore, and certainly insufficient to support a human skater. Mankind has been damaging the planet for a very long time, as Cowper’s book of 1899 also records:
“When you take up this volume you are asked to bear in mind that rural England is changing very fast; that ever since the first steam locomotive started on its smoky journey, the doom of old fashions, old industries, and old ideas was sealed. How radical these changes have been, and how relentless is the impulse which is effacing the old world colouring of rural life...”
Mankind’s selfish greed, and the environmental chaos it is causing, is not new, and is unlikely to change in a hurry.
By 1930, the Marshall family wanted to sell their Monk Coniston estate, which they eventually sold to Beatrix Potter and her husband, William Heelis, for a remarkable £15,000. Today that sum would buy barely two acres. As part of the purchase, Beatrix Potter had arranged with the National Trust that through a public appeal the Trust would buy back slightly more than half of the estate’s 4000 acres from her. They did so, with Beatrix Potter later donating the last part of the land to the National Trust anonymously.
As I sat on my knoll, looking at the scenic tarn several hundred metres distant, I thought of what Beatrix Potter might say if she was sat beside me. She truly adored Tarn Hows but I wager now would be disappointed. Holding that thought, I struggled to my feet and headed slowly towards the tarn, the effects of climate change clearly visible around me.
Historically, Tarn Hows once epitomised the quintessential winter wonderland. The rolling hills surrounding it were routinely blanketed in snow, and the tarn itself often froze over. Recent winters have painted a different picture. There has been a marked decrease in snowfall, and the tarn freezing over has become a rarer event. These changes are consistent with global climate change and carry significant ecological consequences.
The reduced snowfall affects both flora and fauna. Snow acts as an insulator for the ground, protecting it from winter temperatures. Without snow, ground frost can feature, which is detrimental to some plant species. Take bracken as an example, which has a root system that is easily damaged by frost. Bracken covers much of the land both beyond and around Tarn Hows.
Ecological effects of bracken
Changes in farming methods have led to an increase in bracken in the Lake District. As the number of sheep on the fells has decreased the bracken has spread. There may be 500,000 people in Cumbria and still three million sheep[x], but the Herdwick sheep[xi], so classic of the Lake District, is still in decline. Its population has more than halved in the past century[xii].
Bracken’s vigorous growth, which allows it to extend its area by up to 3% each year, excludes most other plants, such as bilberry and heather that might otherwise be growing. It is also an ideal habitat for ticks which are more than happy to latch on to anything or anyone that passes, and occasionally transmit Lyme Disease.
Bracken is a remarkable plant. It is one of the oldest ferns on Earth, with fossil records dating back over 55 million years. It grows on every continent, apart from Antarctica, and can be home to many invertebrates, including several moths and caterpillars. Larger animals can feed on bracken, or use it as cover, while ground nesting species of moorland birds, such as skylarks and lapwings, use deeper stands of bracken as food and nesting sites, as well as cover[xiii]. More frost means less snow, which in turn means less bracken. That may be no bad thing for a hillwalker but is certainly to the detriment of the flora and fauna of Tarn Hows.
Because species that are adapted to snow-covered environments are now finding these conditions less common, certain established wildlife spectacles are harder to see. These include starling murmurations, the white mountain hare, scurrying red squirrels, short-eared owls, mating foxes, laughing green woodpeckers, wandering mallards, and plenty more[xiv]. These animals need to readjust.
Mammals
Many mammals, for example hedgehogs and some bats, hibernate during the winter to conserve energy and survive harsh conditions. With milder winters, these animals are altering their hibernation patterns, staying active for longer, or reducing the depth of their hibernation. These changes impact the animal’s energy expenditure and overall health. This said, it is not all bad news, as some studies have suggested that climate warming can increase the chances of reproductive success[xv]. There are contrasting effects, depending on the mammal involved[xvi].
Some mammals, including small rodents such as field voles, will change their activity during milder winters. A reduction in snow cover and milder temperatures allows these species to remain active and forage for food throughout the winter months. As this is unusual behaviour that has been created by climate change, there is increased competition for resources and an alteration in the predator-prey interaction[xvii].
Milder winters also affect the reproductive behaviour of mammals. Red squirrels, for example, may have extended breeding seasons because food may be available throughout winter, whereas previously it was not. This leads to changes in population dynamics and impacts the reproductive success of the species[xviii].
Climate change also influences the distribution of mammals as they slowly adapt. Some species expand their ranges to higher elevations or latitudes, seeking suitable habitats. This has a cascading effect on local ecosystems, as interactions between species change[xix].
Tarn Hows’ water
Less snowfall also means a reduction in snowmelt, which contributes to the water level of the tarn. This leads to lower water levels in late winter and early spring and affects both aquatic life and the quality of the habitat for wetland species. Tarn Hows’ water is also not as pure as it looks. Although it has been given good ecological status by the Department for Environment Food & Rural Affairs, it failed its analysis for mercury, and for polybrominated diphenyl ethers (PBDE) in 2019[xx]. Overall, just 16% of England’s waters (14% of its rivers) meet the criteria for good ecological status[xxi].
Mercury is a concern because it is extremely poisonous, and can be absorbed by touch, inhalation, or consumption. It builds up in the body with each exposure and is very difficult to remove. It is one of the most serious contaminants threatening the nation’s waters because it is a potent neurological poison in fish, wildlife, and humans. It is a global pollutant that ultimately makes its way into every aquatic ecosystem through either point-source discharges or atmospheric deposition. Coal-fired power plants, and the atmospheric deposition they create, turn out to be the largest source of mercury for the atmosphere[xxii]. It beggars belief that, in December 2022, the UK Government actually supported a new coal mine being developed in Whitehaven, 40 kms (25 miles) to Tarn Hows’ north-west, and one can only hope that before construction begins, they will see sense[xxiii].
PBDEs can damage health as well and belong to a class of chemicals that are added to certain manufactured products to reduce the chance that a product catches fire. Examples might be rugs, upholstery, and even personal computers. PBDEs do not dissolve easily in water and can settle to the bottom of rivers and lakes. Some PBDEs will accumulate in certain fish and mammals when they eat contaminated food or water, with the pollutant affecting the thyroid, liver, and brain. More research is needed to assess the human health effects of exposure to PBDEs[xxiv] but the findings are unlikely to be happy ones.
The increased temperatures associated with climate change also impact water quality in Tarn Hows as there is a higher chance that algal blooms can appear, which will deplete oxygen levels and harm aquatic life. Additionally, changes in precipitation patterns affect the flow of nutrients from the surrounding land into the tarn, thereby leading to eutrophication and the proliferation of harmful algal species. Blue-green algae have not yet been reported in Tarn Hows but have been seen in Coniston, Esthwaite, and Windermere North Basin[xxv]. Each is a short hop away from Tarn Hows.
Tarn Hows water may look beautiful, but there are dangers lurking within.
As temperatures steadily rise, the waters of Tarn Hows, indeed of other freshwater bodies as well[xxvi], begin to disrupt the delicate balance of the aquatic ecosystem by altering the behaviour, physiology, and distribution of aquatic species. Some species may thrive in these conditions, while others may struggle to survive.
Phenology refers to the timing of natural events, such as the emergence of aquatic insects and the spawning of fish. Rising temperatures and altered precipitation patterns lead to shifts in phenology, and thereby affect the synchronicity between species' life stages and their prey. The result is reduced reproductive success and declining populations of key species. Evidence that this is occurring in the Lake District is already clear[xxvii].
Climate change is associated with more frequent and intense weather events, such as heavy rainfall and flooding. These disrupt the aquatic ecosystem of Tarn Hows by washing sediment and pollutants into the water, altering water levels, and causing physical damage to habitats. Such disturbances negatively impact the health and diversity of aquatic species. For example, Tarn Hows is home to several fish species, including brown trout and arctic char. Warmer water reduces the availability of suitable habitats for these fish[xxviii], and a shift in species composition that disrupts the overall health of the ecosystem. Thankfully, fishing is no longer permitted at Tarn Hows[xxix].
Amphibians are also affected, for example the common frog and smooth newt, as they rely on stable aquatic environments for breeding and larval development. Changes in water quality and habitat availability impact their reproductive success and survival. The same applies to insects, which serve as a food source for many fish and bird species.
In Nature, everything connects to everything else.
***
You are now roughly halfway, and I insist you take a rest. A cup of something, a glass of the other, a breath of air, a chat, whatever you decide. Make it a few days if you desire. A break will help you focus as it is your attention that I beg. There is much to read, plenty to learn, and my Lake District has many stories to tell. Please return refreshed, whenever you decide, and then on with the remainder...
***
Part 2
Domestic animals and their impact
As I walked around Tarn Hows, I was struck by what little evidence of wildlife I could see. There was clearly some, but not much. There were badger runs, signs of deer stripping bark, the holes of small rodents, fir cones nibbled by squirrels, but not many prints. Those I did see were made by mammals, for sure, but mostly they were human. Prints made by boots, trainers, shoes, sandals, and the occasional wheels of a buggy or wheelchair. I saw no bare human feet. Many of the humans had dogs. I love dogs, but dear me. A very successful way of deterring wildlife is to keep a domestic dog or cat, which may explain the lack of animal tracks and runs I saw at Tarn Hows.
Domestic animals are a problem for several reasons, and not only exacerbate climate change, but are more at risk because of it[xxx]. For example, a typical cat can produce 310kg of carbon dioxide (CO2) annually. Meanwhile, a dog can generate 770kg. A large dog, say a Dobermann, can emit upwards of 2500kg of CO2 each year, which is twice as much as the emissions from an average family car[xxxi].
For perspective, in 2022 the global CO2 emissions per human being was an average of 4.66 metric tons, compared with 3.11 metric tons in 1960[xxxii]. A Dobermann, and based on 2500kg being 2.5 metric tons[xxxiii], thus emits more than half the global average of CO2 per person. Different countries have different levels of emission, but a Dobermann in UK is roughly the same as a human being in Tunisia. The lowest CO2 emitter in the world is Greenland, with 0.03 metric tons of CO2 per person per year. The highest is Qatar, with 38.14 metric tons per person per year[xxxiv], and rising.
The effects on climate are one thing, the effects on wildlife are another. Domestic cats (Felis catus) are predators that humans have introduced globally and that have been listed among the 100 worst non-native invasive species in the world. Free-ranging cats on islands have caused or contributed to 33 (14%) of the modern bird, mammal and reptile extinctions recorded by the International Union for Conservation of Nature (IUCN) Red List[xxxv]. Mounting evidence from three continents indicates that cats can also locally reduce mainland bird and mammal populations[xxxvi] and cause a substantial proportion of total wildlife mortality[xxxvii]. The numbers are frightening. One study, just looking at the USA, estimated that free-ranging domestic cats kill 1.3-4.0 billion birds and 6.3-22.3 billion mammals annually[xxxviii]. Near one sharp turning of the Tarn Hows path, I saw feline tracks. I cannot say if the animal was domesticated or wild but there were cats about, and very little wildlife.
Domestic dogs are unfortunately no better, and much work has been done on this. People and their dogs disturb wildlife, with dog owners not always being willing to acknowledge the problem. Wildlife perceives dogs as predators and dogs displace other animals from habitats, while dog scent repels wildlife for lengthy periods.
This can induce long-term stress in wild animals, impact their immune systems, and reduce reproduction. Dogs also spread disease and can kill wildlife, either directly or indirectly. People with dogs are far more detrimental to wildlife than people alone. Off-leash dogs are worse, and off-trail impacts are the highest, the bits that a dog walker may not see. Research has already shown that wildlife activity is reduced within 100 metres of trails where domestic dogs may be found[xxxix]. There is a telling conclusion of research undertaken in 2019, which reads as follows:
“The evidence that dogs negatively impact wildlife is overwhelming. It is clear that people with dogs - on leash or off - are much more detrimental to wildlife than people without dogs. Dogs (Canis lupus familiaris) are considered to be a subspecies of wolf (Canis lupus), and wildlife perceive dogs as predators[xl].”
Research from Australia, New Zealand, the USA, India, and South Africa found that kills by dogs threatened 188 species worldwide and led to the extinction of 11 vertebrate species[xli]. A Polish research group found that in Poland alone, dogs were responsible for killing more than 33,000 wild animals per year[xlii].
Many readers will have dogs or cats, and will benefit enormously from them, so I will leave this topic here. However, these facts are the reality and it worth all considering what must be done to encourage and preserve wildlife. Certainly, I see problems in Lakeland with dog walkers and pets, both in the fells and beside my renatured land. The effects are inescapable and the reason why I found wildlife difficult to find at Tarn Hows was plain to understand.
Littering and environmental consequences
Many of the human walkers at Tarn Hows also failed to clean up after themselves. Not only was there dog scat that had been left where it lay, but there were sweet wrappers, too. The Lake District generally, and Tarn Hows specifically, is not a good advertisement for litter. Lakeland produces approximately 7000 metric tons of waste each year, much of it generated by visitors. A 2021 survey suggested that 72% of visitors to the Lake District admitted to leaving litter behind during their visit[xliii].
Indirectly, litter increases greenhouse gases by either decomposing in the environment or being transported to waste disposal centres by vehicles. Litter also harms wildlife - one million birds and 100,000 marine mammals and sea turtles die annually having ingested, or been trapped by plastic[xliv].
Even when litter is collected and finds its way to the nearest dump, the waste sector is one of three key methane-emitting sectors, following agriculture and fossil fuels, and is responsible for 20% of human-driven methane emissions globally. Methane is over 80 times more potent than CO2 as a climate pollutant[xlv].
The message? Do not leave litter lying around and stay well away from plastic.
Conservation grazing with Belted Galloway cattle
In many places beside Tarn Hows were the footprints of cattle, the Belted Galloway, which is generally an animal with a quiet, calm disposition[xlvi]. It is unlikely to chase you. Although a Belted Galloway is reared mainly for beef, it is excellent for conservation grazing. There is a difference between cows and sheep in this respect. Sheep use their lips and front teeth to select individual plants, targeting only their favourite species - often delicate wildflowers. Over time this reduces the diversity of pasture as it becomes dominated by the plants sheep prefer not to eat. For example, iris, holly, and St John’s Wort are poisonous to sheep[xlvii].
Cows differ as they wrap their tongues around clumps of vegetation to pull it up, creating small patches of bare earth ready to be populated by new seeds. They are also less picky - their gut is capable of digesting tougher plants and their size means they need plenty to keep going.
Weight is also a factor. Cows churn up the ground, creating soft, muddy pockets for seeds to germinate. A cow’s size means it breaks up dead leaves on the ground and creates pathways through tall, dense areas. Far from being destructive, a cow’s movements provide other species a place to thrive.
Cows are so suited to this role that even their manure has a use. Manure is a natural fertiliser which also supports a variety of insects such as beetles, flies, and spiders, as well as earthworms. In turn, birds and bats feed off these invertebrates, thereby continuing the cycle. There is no modern way to replicate the efficacy of cattle grazing when it is done with Nature in mind[xlviii]. It is why Belted Galloway cattle are to be found at Tarn Hows.
Birds
Tarn Hows can be a bird watcher’s paradise, and I passed several birders almost glued to their binoculars. One couple became especially excited when they spotted a tree creeper[xlix], although that was their sole sighting of the day. Apart from the tree creeper reported to me, an inquisitive robin redbreast[l], and the “caw” of a distant crow, I heard and spotted nothing. Both crows and ravens are to be seen around Tarn Hows. There is a difference in the sounds made by the two birds, with the raven sounding slightly raspy, as it makes more of a “kraa” than a “caw”[li].
Climate change is having a major impact on birds, as their migration patterns alter, as does their foraging behaviour, in addition to their breeding and nesting times. There are clear changes in migration behaviour taking place. Some bird species are staying at Tarn Hows longer, and returning earlier, than would normally be expected. This leads to competition between resident and migratory bird species[lii].
Warmer temperatures influence the timing of insect appearance and plant flowering, thereby affecting the synchronisation between bird species and their prey. This leads to changes in foraging behaviour. Research in 2014[liii] identified reported changes in the diet composition of great tits in response to shifts in caterpillar availability linked to climate change, so birds are being forced to adapt.
One of the most visible impacts of climate change on bird behaviour is the alteration of breeding and nesting times. Rising temperatures lead to earlier springs, causing some bird species to advance their breeding season. This shift affects the availability of crucial resources such as food and nesting sites. This leads to competition that might not otherwise have occurred, in addition to reduced reproductive success[liv].
Vegetation
Tarn Hows, with its unique ecological makeup, is also experiencing a raft of changes that profoundly affect its plant life. Rising temperatures have caused many plant species to start their growth and reproductive stages earlier in the year, thereby disrupting the synchronisation of flora with pollinators and other ecological partners. Research by the Lake District National Park Authority's ecological monitoring team has identified advance flowering in several native plant species, including bluebells (Hyacinthoides non-scripta) and foxgloves (Digitalis purpurea). Many species now emerge and reproduce earlier in the year, which is likely a biological response to shortened winters, earlier onset of the growing season, and prolonged droughts[lv],[lvi].
As flora respond to changing climatic conditions, they do not always align with the appearance of their pollinators, including bees and butterflies. Such mismatches compromise successful pollination and seed set, and affect plant reproductive success and the availability of food resources for local wildlife. A study conducted in the Lake District, found that earlier flowering in plants because of climate change was leading to phenological mismatches with their pollinators, thereby threatening both plant and pollinator species[lvii].
As temperatures continue to rise, some plant species native to Tarn Hows face difficulty thriving in their current habitats. This triggers a migration of flora to more suitable locations, such as higher elevations, and impacts the overall composition of the ecosystem. A recent study by botanists at the University of Cumbria, which included Tarn Hows in its study, documented altitudinal shifts of plant species towards higher elevations in response to rising temperatures. Species like the crowberry (Empetrum nigrum)[lviii] are now being found at elevations previously unoccupied. With every 100 metres of ascent, the temperature drops by an average of 0.65°C. Where the air is very dry, such as in an area of high pressure, the air can cool by almost 1°C per 100 metres of altitude[lix].
Climate change's propensity for extreme weather events poses a significant threat to Tarn Hows' flora. Prolonged droughts, severe storms, and heavy rainfall cause physical damage to plant populations, disrupt nutrient cycling, and lead to soil erosion, jeopardising the survival of certain species. Observations by the Lake District National Park Authority have revealed instances of severe storm damage to the native oak (Quercus robur) and beech (Fagus sylvatica) populations at Tarn Hows, resulting in reduced canopy cover and potential long-term ecological repercussions.
My walk around Tarn Hows was at times depressing, as so many trees had been felled. The chainsaws had been busy. There were certainly buds on many of the surviving deciduous trees but in several places, what was once woodland had become open ground, largely populated by bracken. Thanks to the many larch trees that have been planted at Tarn Hows, the root fungus Phytophthora has crept in. Its ramorum species can cause what is sometimes known as larch disease. This first entered the United Kingdom in 2002 on an imported Viburnum[lx]and spread from there to other plants and trees, the larch especially. It is thought by many to be the world’s most historic and economically significant genus in plant pathology[lxi]. A warming climate increases the virulence of Phytophthora[lxii], which does not bode well for the future.
However, it was not all tree misery at Tarn Hows, there was some mystery and delight as well, as I came across several money trees. This is when a low denomination coin is hammered into a tree or tree stump by a passer-by, a practice that is believed to have begun in the 1700s[lxiii]. Some consider this tradition brings good luck and health to those who hammer in the coin. Should an invalid do this, it might take away their illness, or so it has been claimed. Conversely, if someone tries to remove a coin that has been hammered in, they may fall severely ill. Who knows if any of this is right. Being superstitious, I gave each money tree a wide berth. I can think of no association between climate change and money trees, other than a money tree is evidence of mankind’s existence. Mankind is manifestly not taking climate change seriously and is suffering as a result.
Insect activity
Climate change has resulted in shifts in the phenology of insect species at Tarn Hows. The timing of insect appearance, such as when they become active in the spring or when they go into hibernation, is closely linked to temperature. As temperatures warm, some insect species emerge earlier in the year, affecting their interactions with flowering plants. Ongoing studies conducted by entomologists from the University of Cumbria, in collaboration with the Lake District National Park Authority, have observed the early appearance of bumblebee species (Bombus spp.) in response to rising spring temperatures at Tarn Hows. This is in addition to the early bumblebee[lxiv] (Bombus pratorum), which is seen in the first part of spring anyway. The early bumblebee is an interesting insect as it is not fussy about what it pollinates and is known to visit more than 140 species. Compare that with the yucca moth that only pollinates the yucca plant[lxv], and nothing else at all. There are no yucca moths at Tarn Hows, for sure, nor yucca.
As both plants and insects respond to climate change by altering their phenological patterns, mismatches may occur. For instance, if flowering plants bloom earlier but their pollinators do not adjust correspondingly, pollination is disrupted. Research conducted at Tarn Hows by the University of Cumbria has shown instances of phenological mismatch between the early-flowering bilberry (Vaccinium myrtillus) and some bumblebee species.
In response to milder winters and warmer temperatures, some insect species extend their active periods throughout the year. Extended activity impacts the availability of pollinators for plants during specific flowering seasons and leads to disruptions in plant-pollinator relationships. At Tarn Hows, local observations have noted extended activity of hoverflies (Syrphidae) during the late autumn and early winter months. Hoverflies are important pollinators of many wild plants[lxvi] and have been seen to be active around plants such as heather (Calluna vulgaris) and ivy (Hedera helix).
Climate change also leads to changes in the composition and abundance of insect pollinators. As certain species thrive under the new climatic conditions, they may become more dominant in the pollinator community in a way that was not formerly the case. Observations at Tarn Hows' have documented an increase in the prevalence of the tree bumblebee (Bombus hypnorum), which is now a more frequent visitor to flowering plants such as red campion (Silene dioica).
Changes in pollinator behaviour have significant implications for plant reproduction. Reduced pollination results in a lower seed and fruit production. This affects plant populations and the availability of resources for other wildlife. A recent study conducted by the Lake District National Park Authority has shown decreased seed production in heather (Calluna vulgaris) because of phenological mismatches with pollinators. This impacts the availability of food resources for herbivorous insects.
The survival of many insect species during the winter months depends on their ability to overwinter successfully. Milder winters affect their overwintering, as they are more vulnerable to temperature fluctuations and increased predation. Research conducted by ecologists from Lancaster University at Tarn Hows has shown that milder winters have led to increased winter survival rates for the common European earwig (Forficula auricularia) due to reduced cold stress. The earwig is showing an ability to adapt to climate change[lxvii].
Climate change also influences the distribution of insect species. Warmer temperatures enable some insects to extend their geographic range to higher elevations or latitudes, just as can be seen with certain plants. These range expansions result in the introduction of new species to Tarn Hows and impact existing insect communities. Recent surveys by the Lake District National Park Authority have recorded the presence of southern dragonfly species, such as the common darter (Sympetrum striolatum), which were previously rare in the region. Now it is the turn of the dragonfly to demonstrate some ability to adapt to climate change, although there have also been some extinctions[lxviii].
Today’s Tarn Hows
The Tarn Hows we see today is not the same as that witnessed by our forefathers. It is also not the same as will be seen by those who follow us. Climate change is altering our world in unpredictable ways. Not only is mankind adapting, but so are the flora and fauna around. Tarn Hows is showing that adaptation clearly. The climate has changed before, thanks to a variety of reasons, but on this occasion, there is only one real culprit, whose head is so far into the sand it would be laughable, were it not so tragic. That culprit is mankind.
All any of us must do to establish the cause of our changing climate is to look in a mirror. It really is that simple.
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References
[i] Tarn Hows Lake – Tourist Information and Pictures. 28 March 2013. See https://viewbritain.com/england/tarn-hows/#:~:text=Tarn%20Hows%20attracts%20over%20500%2C000,river%20flow%20or%20rain%20water. Accessed 16 January 2024.
[ii] Wikipedia. Tarn (lake). See https://en.wikipedia.org/wiki/Tarn_(lake)#Etymology. Accessed 18 January 2024.
[iii] Miles Without Stiles 13: Tarn Hows. See https://www.lakedistrict.gov.uk/visiting/things-to-do/walking/mileswithoutstiles/mws13. Accessed 16 January 2024.
[iv] Rushworth J. Only true Cumbrians will recognise these expressions. 29 November 2023. See https://www.lancs.live/news/local-news/how-well-you-know-cumbrian-26072220. Accessed 16 January 2024.
[v] Wikipedia. Cumbrian dialect. See https://en.wikipedia.org/wiki/Cumbrian_dialect. Accessed 16 January 2024.
[vi] Cailler A. Ghostly figures captured in eerie photo taken at Lake District beauty spot. 21 December 2021. See https://www.dailystar.co.uk/news/weird-news/two-ghostly-figures-captured-eerie-25752769. Accessed 176 January 2024.
[vii] Wikipedia. Inclosure Acts. See https://en.wikipedia.org/wiki/Inclosure_Acts. Accessed 16 January 2024.
[viii] The history of Tarn Hows. See https://www.nationaltrust.org.uk/visit/lake-district/tarn-hows-and-coniston/the-history-of-tarn-hows. Accessed 16 January 2024.
[ix] Cowper HS. Hawkshead: (the northernmost parish of Lancashire) its history, archaeology, industries, folklore, dialect, etc., etc. Publ. London Bemrose 1899
[x] Peck K. 8 facts you never knew about the Lake District. 30 January 2019. See https://www.hpb.co.uk/blogs/8-facts-you-never-knew-about-the-lake-district#:~:text=8)%20The%20Lake%20District%20has,means%20they%27re%20rather%20outnumbered! Accessed 18 January 2024.
[xi] Learn all about Herdwick sheep. See https://www.herdy.co.uk/the-farming-year/all-about-herdwicks/#. Accessed 18 January 2024.
[xii] Herdwick sheep numbers declining in native Lake District. 10 September 2020. See https://www.bbc.co.uk/news/av/uk-england-cumbria-54101532. Accessed 18 January 2024.
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[xxiii] A new coal mine in Cumbria? See https://slacc.org.uk/cumbria-coal-mine/#:~:text=Despite%20Michael%20Gove%27s%20approval%20of,We%20now%20expect%20a%20High… Accessed 23 January 2024.
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[xxv] Cumbria and Lancashire algal bloom status map. 22 December 2023. https://consult.environment-agency.gov.uk/cumbria-and-lancashire/blue-green-algae-in-cumbria-and-lancashire/user_uploads/blue-green-algae-map-221223.pdf. Accessed 21 January 2024.
[xxvi] UK Climate Change Risk Assessment 2022. See https://assets.publishing.service.gov.uk/media/61e54d8f8fa8f505985ef3c7/climate-change-risk-assessment-2022.pdf. Accessed 16 January 2024.
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[xxviii] Temps for trout: how to catch fish that behave hot n cold. https://www.flyfisherman.com/editorial/Temps-for-Trout-How-to-Catch-Fish-that-Behave-Hot-n-Cold/379972#:~:text=A%20study%20published%20by%20the,survival%20when%20caught%20in%20the. Accessed 21 January 2024.
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[xxx] Narayan E. How climate change will affect your poet – and how to help them cope. 6 August 2023. See https://www.preventionweb.net/news/how-climate-change-will-affect-your-pet-and-how-help-them-cope#:~:text=Climate%20change%20and%20associated%20heat,cats%20and%20dogs%20at%20risk. Accessed 17 January 2024.
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[xxxii] Average per capita carbon dioxide emissions worldwide from 1960 to 2022. See https://www.statista.com/statistics/268753/co2-emissions-per-capita-worldwide-since-1990/. Accessed 17 January 2024.
[xxxiii] Byju’s. See https://byjus.com/question-answer/convert-2500-kg-metric-ton/#. Accessed 17 January 2024.
[xxxiv] CO2 emissions per capita. See https://www.worldometers.info/co2-emissions/co2-emissions-per-capita/. Accessed 17 January 2024.
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[xliii] Litter in the Lake District. See https://www.wastemanaged.co.uk/litter-lake-district/#:~:text=The%20Lake%20District%20produces%20an,litter%20behind%20during%20their%20visit. Accessed 17 January 2024.
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[xlvi] Belted Galloway Society. See https://beltie.org/guidelines-for-selecting.php#:~:text=Disposition%2FBehavior%3A%20Belted%20Galloways%20should,toward%20humans%2C%20even%20when%20penned. Accessed 18 January 2024.
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[xlviii] Our work at Tarn Hows and Coniston. See https://www.nationaltrust.org.uk/visit/lake-district/tarn-hows-and-coniston/our-work-at-tarn-hows-and-coniston. Accessed 16 January 2024.
[xlix] RSPB. Tree creeper (Certhia familiaris). The Treecreeper is a small, very active bird that lives in trees. It has a long, slender, downcurved bill, which it uses to pluck insects from underneath bark. It's speckly brown above and mainly white below. It breeds in the UK and is resident here. Birds leave their breeding territories in autumn but most range no further than 20km. Its population is mainly stable. See https://www.rspb.org.uk/birds-and-wildlife/treecreeper. Accessed 17 January 2024.
[l] RSPB. Robin (Erithacus rubecula). The UK's favourite bird. Thanks to its bright red breast, it's familiar throughout the year and especially at Christmas! Males and females look identical, young birds have no red breast and are spotted with golden brown. Robins sing nearly all year round and despite their cute appearance, they are aggressively territorial and are quick to drive away intruders. They will sing at night next to street lights. See https://www.rspb.org.uk/birds-and-wildlife/robin. Accessed 17 January 2024.
[li] GrrlScientist. Caw vs. Kraa: meaning in the calls of crows and ravens. See https://www.theguardian.com/science/grrlscientist/2014/oct/18/caw-vs-kraa-meaning-in-the-calls-of-crows-and-ravens#:~:text=Both%20crows%20and%20ravens%20make,in%20addition%20to%20these%20calls. Accessed 17 January 2024.
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[lix] Decreases in temperature with altitude. See https://www.meteoswiss.admin.ch/weather/weather-and-climate-from-a-to-z/temperature/decreases-in-temperature-with-altitude.html#:~:text=As%20altitude%20increases%2C%20temperature%20decreases,°C%20per%20100%20metres. Accessed 23 January 2024.
[lx] Phytophthora ramorum. https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/tree-pests-and-diseases/key-tree-pests-and-diseases/phytophthora-ramorum/. Accessed 21 January 2024.
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[lxiii] The mystery behind the money trees of England. 24 July 2019. See https://timesofindia.indiatimes.com/travel/destinations/the-mystery-behind-the-money-trees-of-england/articleshow/70363708.cms#:~:text=Some%20believe%20that%20this%20tradition,they%20will%20fall%20severely%20ill. Accessed 17 January 2024.
[lxiv] Early bumblebee. See https://www.cumbriawildlifetrust.org.uk/wildlife-explorer/invertebrates/bees-and-wasps/early-bumblebee. Accessed 22 January 2024.
[lxv] Wikipedia. Yucca. Yuccas have a very specialized, mutualistic pollination system; being pollinated by yucca moths (family Prodoxidae); the insect transfers the pollen from the stamens of one plant to the stigma of another, and at the same time lays an egg in the flower; the moth larva then feeds on some of the developing seeds, always leaving enough seed to perpetuate the species. See https://en.wikipedia.org/wiki/Yucca. Accessed 23 January 2024.
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