Ullswater Valley: Rewilding & Invasives

Ullswater Valley: Rewilding Options 

What should and shouldn’t be here

Following the last Glacial Maximum (Ice Age), as the ice sheets retreated from the deep troughs of the Lake District, the Ullswater valley began to breathe. Before the arrival of human settlers, the landscape was a dynamic mosaic of Oak, Birch, and Scots pine—interspersed with wetlands and high-altitude mountain heath. This was a place of immense biological complexity, where the interaction between Fungi, Flora, and Fauna was self-sustaining and robust.

Today, rewilding throughout the Lake District, and Cumbria as a whole, is a movement gaining massive momentum among a population that is becoming highly educated and ever more aware of the benefits of nature recovery. Surveys constantly show that the vast majority of people support the restoration of our lost natural heritage. This shift is driven by the clear ecological benefits: restoring keystone species repairs the broken cycles of the valley, improving soil health, and providing natural flood management. Furthermore, the financial benefits to locals are significant; a thriving, life-rich valley attracts high-value eco-tourism, such as kayaking on Ullswater, and creates jobs in habitat restoration and land management that far exceed the returns of the depleted monocultures of the past millennium.

Successful Precedents: Lessons from around Europe

To understand what is possible for Ullswater wildlife, we can look to these established nature-based solutions where the transition to ecological restoration has yielded tangible results:

• Haweswater Reservoir (Cumbria, UK): Managed by the RSPB, this site has shown that reducing sheep numbers restores the natural sponge of the fells.

• South of Scotland Golden Eagle Project: Successfully translocated over 30 eagles, sparking a raptor-based economy.

• Cairngorms Connect (Scotland): A massive partnership project restoring habitats from river valley to mountain top.

• Carrifan Wildwood ( Southern Scotland ): Rescuing the wooded wilderness of the Southern Uplands that existed there for thousands of years before human activities became dominant.

• The Oder Delta (Germany/Poland): A trans-boundary wilderness that has revitalised rural villages through sustainable hospitality.

• The Millingerwaard (Netherlands): Removed dykes to allow natural flooding, solving flood safety issues for local residents.

• The Iberian Highlands (Spain): Reintroducing vultures and lynx to prevent rural depopulation.

• Wildwood Trust. Wildwood is a native species conservation charity established in 2002 to push the boundaries of innovative conservation and rewilding.

On the land: Lake District Predators and Engineers

Apex Predators

Eurasian Wolf

• Likelihood of Return: 0/10 (for now)
• The Reality Check: Wolves are one of Europe’s great keystone predators, capable of influencing deer behaviour and numbers and, in turn, vegetation and woodland regeneration. They do not require completely wild landscapes, but a viable population needs large areas of suitable habitat, sufficient prey, connectivity and a realistic way of managing conflict with people and livestock. The 21st-century Lake District is highly fragmented, heavily used and densely settled in places, making a self-sustaining wolf population around Ullswater highly unlikely under current conditions.
• Sustainable Alternative: The Scottish Highlands offer far larger and less densely populated areas in which the ecological feasibility of wolf restoration has been studied. Modelling has suggested that substantial populations could potentially be supported there, although the ecological, social and management challenges remain considerable.

Eurasian Lynx

• Likelihood of Return: 0/10 (for now)

• The Reality Check: Even the quietest parts of the Lake District lack the immense, unbroken scale required for a self-sustaining population of Lake District predators. While pockets like Ennerdale or Thirlmere could harbour individuals, the region remains an island of habitat.

• The Border Prospect: Kielder Forest is often cited as the most suitable English release site. However, estimates suggest it could only support maybe 30 animals, which sits on the cusp of ecological viability.

• Sustainable Alternative: The Galloway Forest and Southern Uplands in Scotland have the carrying capacity for roughly 50 Lynx, while the Scottish Highlands could potentially support 250.

Ecosystem Engineers

Wild Boar

• Likelihood of Return: 0/10 (for now) (around Ullswater)

• The Reality Check: Due to high tourism, Ullswater is an unlikely site for release. However, Boar have reintroduced themselves via escapes in the Forest of Dean and parts of the Scottish Highlands, where they are already functioning as ecosystem engineers.

European Bison

• Likelihood of Return: 10/10 (Introduced in Cumbria)

• The Reality Check: As of 2026, five European bison have been introduced on a trial basis onto a managed site at Castletown Estate up near the Solway Firth in Cumbria. They are not there to be visited. These massive ecosystem engineers are used to open up dense woodland canopies and restore natural processes through distinct, heavy impact behaviour.

  Rather than knocking over mature trees, bison gently clear the undergrowth by forging pathways through dense scrub, rubbing their massive bodies against trunks to shed their thick winter fur, and selectively stripping bark from specific tree species. Crucially, they also roll on the ground to create massive “dust baths” or sand wallows. It’s a well known truism that there are no straight lines in nature, and that ‘ messy ‘ means life. This is exactly what these beautiful animals contribute.

• Like to know more about how they interact with the land ? Check out this video from the wonderful Leave Curious.

Eurasian Beaver

• Likelihood of Return: 9/10

• Benefit: The ultimate engineer for climate resilience. Their leaky dams slow water flow, providing a natural buffer that could protect infrastructure around Ullswater.

• Ongoing Projects: Cumbria is currently at the forefront of beaver restoration with two primary focal points:

  • Lowther Estate: Since 2020, this site has hosted a successful scientific trial in a private 27-acre enclosure. As of 2026, the beaver family is thriving, demonstrating how quickly they can transform dry pasture into a lush wetland mosaic.

  • Wild Ennerdale: In a major milestone for 2026/7, the Wild Ennerdale partnership, which includes Forestry England has advanced plans for what could be the largest reintroduction in England to restore natural processes of the River Ehen catchment.

Eurasian Otter

• Status: Recovered naturally.

• The Mink Conflict: For decades, invasive American Mink have been causing havoc in our waterways. Because the mink is a versatile, aggressive predator with no natural enemies here, it decimated local populations of Water Voles.

• The Otter Solution: Otters act as riparian guardians through spatial competition. They drive mink away from the best territories and food sources. As otter populations have recovered, mink have been forced into less favourable, inland habitats where they are easier to control.

Water Vole

• Status: Reintroduced (2023-2026).

• Benefit: Known as landscape gardeners, voles graze on over 200 different plant species. Their burrowing and feeding patterns promote a diverse mix of riparian vegetation, preventing any single plant species from dominating the bankside.

Pine Marten

• Likelihood of Return: 10/10 (Confirmed Breeding)

• The Guardian of the Red Squirrel: Martens primarily hunt the heavier, slower invasive Grey Squirrel. Native Reds are lighter and can retreat to the thinnest outer twigs where a marten cannot follow.

• Psychological Restoration: Their presence restores a natural psychological balance to the woods. Native Red Squirrels co-evolved with martens and possess an innate fear response to their scent, which keeps them alert and avoids risky foraging behaviour. Once again, as the Greys didn’t develop alongside the Martens, they don’t have that natural behaviour response and it’s a Grey Squirrel snack for the Marten.

In the sky: Lake District Predators & Scavengers

Golden Eagle

• Likelihood of Return: 8/10

• SSGP Support: Much of the credit for the eagle’s return to Cumbrian skies belongs to the South of Scotland Golden Eagle Project.

• Sightings: While they have not yet re-established permanent territories in the valley, these majestic birds have already been the subject of occasional eye witness sightings once again over the crags and fells of Ullswater.

Sea Eagle / White-tailed Eagle

• Status: 2026 Reintroduction Proposals.

• A Strategic Link: The Cumbrian White-Tailed Eagle Project has identified the Northern Lake District as a vital corridor. As proposals suggest releasing a minimum of 66 of these stunning birds over a five year period, if such a scheme happens, there would be an excellent chance of observing them over Ullswater, and especially Haweswater Reservoir, as it’s far less populated, and ongoing rewilding projects are proving to be very successful there.

Osprey

• Status: Established nesting pairs.

• Nesting Sites: Bassenthwaite Lake remains the heart of their Lake District recovery. Watching an osprey dive for fish is a hallmark of a recovering wild landscape for anyone kayaking on a lake.

In the soil: Foundations

Mycorrhizal Fungi (The Wood Wide Web)

• Role: These symbiotic fungi form vast underground networks that connect the roots of trees, grasses and other plants across the valley.

• Nutrient Exchange: This ancient underground economy is the foundation of a healthy valley. Mycorrhizal fungi scavenge the soil for essential nutrients and deliver them directly to the roots. In exchange, the trees pay the fungi with sugar produced through photosynthesis. This trade is vital for survival in the thin, acidic soils of the fells.

There are two main types :

Ectomycorrhizal Fungi (ECM) — The “Outer” Tree Partner

• Where it lives: Surrounds the root. The fungal threads (hyphae) form a dense glove or sheath around the outside of the root tips and weave between the outer root cells, but never break into the cell walls.

• Plant partners: Mostly trees and woody plants—particularly native broadleaf trees (oak, birch, beech, willow) and conifers (pine, fir).

• Visible sign: These are the fungi that produce classic forest mushrooms above ground (such as boletes, chanterelles, and fly agaric).

 Arbuscular Mycorrhizal Fungi (AM) — The “Inner” Plant Partner

• Where it lives: Enters the root. The fungal threads penetrate through the root cell walls to form microscopic, tree-like structures (arbuscules) inside individual cells to exchange nutrients directly.

• Plant partners: Over 80% of all land plants, including grasses, wildflowers, crops, shrubs, and soft-stemmed plants.

• Visible sign: Entirely microscopic—they do not form large above-ground mushrooms.

The Ullswater Mismatch

On the fells above Ullswater, this subterranean economy is out of sync. Millennia of deforestation compounded by centuries of overgrazing have depleted native ECM fungi, leaving soils dominated by grass-friendly AM fungi. When broadleaf saplings are planted, they struggle to find their fungal partners, leading to high sapling mortality. To combat this, local conservationists use mycorrhizal inoculation introducing native fungal spores to sapling roots before planting so they carry their life-support network with them. Restoring Ullswater’s broadleaf canopy relies on actively rebuilding these invisible fungal pipelines, a task that begins with mapping the hidden biodiversity beneath our feet.

The direction is clear. More and more of the current stewards of the land around the Ullswater area are actively changing behaviours that have dominated the fells for the past 1000 years. This modern shift prioritises a robust local supply chain over historical industrial models that focused more on exported lamb and sheep. Today, an ever-increasing number of local suppliers and restaurants are endeavouring to change the situation by championing the rise of local beef and venison. Crucially, local lamb and sheep farmers are still very much part of the collective; though they are now favouring local buyers where they can over the export trade that, unfortunately, used to dominate for centuries, ensuring that high-quality meat is reared, processed, and consumed within the community.

Nutrient Extraction

Upland sheep grazing functions as a form of long-term nutrient extraction. Sheep consume nitrogen, phosphorus, potassium, and calcium to build bone, muscle, and wool. Because livestock are sold off-site, these minerals are permanently exported from the catchment rather than recycled, and sheep manure alone cannot correct the deficit. On the open high fells, this continuous removal of structural minerals like calcium and magnesium gradually depletes the soil’s natural buffering capacity. This leaves these delicate upland ecosystems increasingly vulnerable to natural acid leaching—a process where heavy rainfall strips away remaining alkaline nutrients, accelerating soil acidification.

Hefting 

Sheep stay in specific hill areas because they are hefted to the land—a learned behaviour where ewes teach their lambs to remain within a specific territory on the open fell. Because sheep gather and graze selectively on their preferred grasses, this creates uneven grazing pressure. High-traffic areas experience heavy localised grazing that suppresses heather regeneration, prevents woodland regrowth, and encourages the dominant spread of tough mat-grass and encroaching bracken, ultimately altering the natural biodiversity and structure of the upland ecosystem.

Soil Compaction and hydrology

High sheep density leads to soil compaction through the Stiletto effect, where concentrated hoof pressure reduces soil porosity and limits its capacity to absorb rainwater. Sheep also form trods—heavily compacted, bare paths—that act as artificial drainage channels during heavy rain. Rather than soaking into the upland vegetation sponge, runoff accelerates down these tracks, increasing soil erosion and downstream flash flooding risks. Reducing grazing pressure allows compacted soils to naturally recover and enables sponge-like mosses to return, improving catchment water retention.

Cattle versus Sheep

Stewards are increasingly reintroducing cattle via managed conservation grazing to create a healthier mosaic of habitats. Unlike sheep, which are highly selective grazers that nibble preferred plants close to the ground, cattle are bulk grazers that eat tall, coarse vegetation in large mouthfuls. Their method of tearing grass with their tongues—rather than surgical cutting with teeth—leaves a varied sward height. Furthermore, a cow’s weight acts as a restorative force; their broad hooves break through thick thatch to expose patches of bare earth. These disturbed pockets serve as vital nursery sites, allowing dormant seeds to germinate and restoring botanical diversity.

Deer around Ullswater

In the absence of natural predators like wolves or lynx, deer populations—particularly Red Deer—have reached large numbers across the Lake District. Without the landscape of fear that predators once provided, deer are free to over browse young saplings and delicate flora across the fells. This lack of natural regulation makes active management and the promotion of local venison essential to prevent these herds from further stripping the vegetation and hindering the natural regeneration of the woodland. By over-browsing young broadleaf saplings, deer interrupt tree root growth—preventing essential ectomycorrhizal (ECM) fungi from establishing in the soil and stalling natural woodland recovery from the underground up.

While the iconic native Red Deer make up the largest presence around Ullswater—with a historic herd numbering in the hundreds around Martindale and the eastern fells—they are not the only species present. Native Roe Deer are widely distributed in the surrounding valley woodlands, while non-native species such as Sika, Fallow, and increasingly Reeves’ Muntjac are expanding across various pockets of the broader Lake District landscape.

To address this growing ecological challenge, regional partners officially launched the Lake District Wild Deer Management Strategy on May 21, 2026. Built on a collaborative foundation between landowners, the National Park Authority, environmental groups, and local deer managers, the strategy operates across five key pillars: Communication, Collaboration, Data & Evidence, Adaptability, and the Lake District Venison Brand. Its processes combine advanced monitoring technology—such as drone thermal imaging, foot counts, and woodland impact assessments—with flexible, landscape-scale culling. The ultimate aim is to regulate deer populations at ecologically sustainable levels, enabling native woodland regeneration, protecting vulnerable habitats, and building a sustainable supply chain for wild local venison.

Policy and Restoration

Local stewards are taking on board the evidence, replacing sheep with cattle and allowing more and more of the land to recover. The Environmental Land Management (ELM) scheme supports this by rewarding “public goods” like soil health. While these actions certainly help rectify past mistakes, history reflects a recurring pattern: Local tenant families once again face the consequences, exiting the land because some tenancies are not being renewed during this transition.

The Invasives: Species That Shouldn’t Be Here

• American Mink: A ruthless predator responsible for the local extinction of Water Voles.

• Grey Squirrel: Carries Squirrel Pox (fatal to Reds) and damages native broadleaf trees.

• Signal Crayfish: Carries plague that kills native crayfish and erodes riverbanks.

• Rhododendron: Blocks all light and poisons the soil.

Trophic Cascades: The Ripple Effect of Restoration

Rewilding is fundamentally about Trophic Cascades—the phenomenon where a change at the top of the food chain trickles down to restructure the entire ecosystem.

• Predation & Fear: Deer move frequently and avoid over-grazing sensitive valley floors.

• Vegetation Release: Native Flora—oak, rowan, and Aspen—finally grows past the browse line.

• Soil Stabilization: Young woodlands anchor the soil, preventing erosion into Ullswater and protecting peat bogs.

• Biodiversity Net Gain: Healthy forests and soils support a surge in insect and bird life.

Conclusion: A Legacy Restored

Ullswater Valley rewilding is the most practical path toward a sustainable future for the catchment. By moving away from the medieval sheep factory model, we allow the three domains of Fungi, Flora, and Fauna to function as they did for millennia. This restoration provides essential climate adaptation while offering a nature-based economy, where visitors can experience a truly wild landscape, perhaps through a quiet morning of kayaking among the hidden bays and restored shorelines. Restoring the life once present is an investment in the valley’s survival for both the ecology and the people who call it home.