A new study has found plants that humans don’t need will ‘lose’ in the face of humanity. Around 46,292 species out of the 86,592 vascular plants studied were categorised as ‘losers’ or ‘potential losers’, many of which are not considered to be useful to humans. Due to this, plant communities of the future will likely be more homogenised. The findings cover less than 30% of all known plant species, highlighting that more work is needed in this field.
A project by the environmental group ‘The Nature Conservancy’ aims to undo the ‘degradation’ of a Kentucky stream. The Long Branch stream was straightened decades ago, altering the flow and natural biodiversity along with increasing erosion. Contractors had previously re-created the natural bends, pools and riffles of the stream, placing rocks, tree root wads and burlap material at some places along the banks. Workers are now planting trees along a section of the stream with the hopes of providing better habitat for a small fish called the Buck darter, which is found only in this watershed.
The UN has launched biodiversity talks on a deal to protect nature. The negotiations began in Geneva on Monday with the deal due for approval later this year. Almost 200 countries plan to adopt a global framework to safeguard nature by mid-century, with a milestone of 30% protected by 2030.
A Squat lobster was seen on Shackleton’s Endurance ship, potentially the first Munidopsis species recorded in the Weddell Sea. It is hard to be certain due to the resolution of the released images but Dr Huw Griffiths from the British Antarctic Survey (BAS) suggested the animal could be from the Munidopsis genus, which contains over 200 known species.
In response to the growing climate and biodiversity crisis, SCOTLAND: The Big Picture is working to drive the recovery of nature across Scotland through rewilding. Using positive storytelling, they hope to inform and inspire change, while also enabling practical rewildling through partnerships and collaborations. They see a role for everyone in creating a wilder Scotland, with a vision of a vast network of rewilded land and water where wildlife and people flourish.
Executive Director, Peter Cairns, has kindly taken the time to answer a few questions for us.
Could you tell us about the work that SCOTLAND: The Big Picture does and how the charity began?
Our core team has been involved in environmental communications for more than two decades so when the rewilding story really started to gain momentum in Scotland, probably about a decade ago, we were well placed to document it. The ‘R’ word (rewilding) remains contentious to this day, but as we embraced it at an early stage, we gradually – and unwittingly – became the voice of the movement, or at least one of them. That gave us a platform and in 2019, we became a fully-fledged charity, working to drive the recovery of nature across Scotland through rewilding, in response to the growing climate and biodiversity crises.
One part of your vision is creating a future for Scotland where people thrive, but development and industry can sometimes be in contention with wildlife. How do you think a nature-based economy could allow for long-term restoration of habitats without negatively impacting communities?
Pitching people against nature helps neither. We need to look for new ways to marry our economic systems with our ecological systems.
We believe the transformational recovery of nature can only be achieved with the support of local communities – rewilding will only work if people can see social, cultural and economic benefits that work in tandem with ecological recovery.
The original principles of rewilding were founded on the ‘3C’s’ – cores, corridors and carnivores, and there’s no reason why such a model can’t be explored in Scotland. ‘Cores’ means areas that are effectively given over to nature, allowing natural processes to shape and govern the land. Around these could be buffer zones, where a high degree of ecological functionality is maintained, but a range of nature-based economic activities, such as payments for natural capital, wild produce and diverse nature-based experiences, help support vibrant communities.
SCOTLAND: The Big Picture was a founding member of the Scottish Rewilding Alliance, how have you found the reception of this alliance amongst organisations? Are they generally in favour of large-scale rewilding in Scotland?
Rewilding has come to mean different things to different people and that can be a challenge, but it also provides opportunity for it to be rolled out at different scales and settings, while still making a valuable contribution to nature recovery. The members of the Scottish Rewilding Alliance are all at different stages on their journey, but all recognise that the traditional models of conservation have failed to arrest and reverse ecological decline, and are committed to a fresh, more ambitious, more holistic approach.
Outside of the Alliance, there is a growing appetite for change across Scotland, as land managers look at the social, political and economic horizon, and realise that business as usual is not an option.
Your upcoming feature-length documentary, Riverwoods, reveals the perilous state of Scotland’s salmon and presents the inextricable relationship between fish and forests. What are the main threats to this species and Scotland’s rivers, and why is salmon such a valuable species for forest ecosystems?
Atlantic salmon is a modern-day canary in the mine – an indicator of ecosystem health. The reasons for its spectacular decline, like so many species, are many and complex, and this film doesn’t attempt to address them all. Instead, Riverwoods tells the story of salmon – young salmon in particular -in our rivers, and carries a simple message: The health of our rivers and all the life within them, is directly dependent on the health of the landscapes through which they flow.
Perhaps to set the scene, I can quote from a recent article we produced on this very subject:
6,000 years ago, a rich, dynamic woodland ecosystem stretched across 60% of Scotland’s land area. These were diverse forests of Scots pine, oak, rowan, birch, aspen and willow; a complex community of shrubs and bushes, tall trees, tiny trees, dead and dying trees, all intertwined in a constantly evolving system.
Flanking Scotland’s rivers and lochs, these woodlands were shaped by beavers, creating fresh coppice growth, new wetlands and backwaters, raising the water table and toppling insect-laden trees into and alongside the river. The decaying timber provided food and sanctuary for more invertebrates, as well as casting dappled shade across the river’s surface.
Spent salmon, exhausted after an epic journey from freshwater to sea and back again, fed brown bears, wolves, eagles, ospreys and otters, before the precious marine nutrients found in their carcasses, were taken up by the soil nourishing fresh plant and tree growth.
In other parts of the world, the connectivity between river, forest and ocean, and the bountiful runs of salmon that still persist, creates a living, breathing, working system. Here in Scotland, just 3% of our native forest remains, clinging on in isolated, lonely fragments and despite their reputation for beauty and drama, the glens through which our rivers run, are often bare and treeless, reflecting the centuries of ecological decline that we have come to accept as normal.
How do you think Scotland’s river catchments can be restored? What changes need to take place?
Fundamentally, we need to perceive and manage river catchments as a complete ecological system and not as a series of individual species and habitats. No species exists in isolation and again, the health of our rivers is dependent on the health of the surrounding landscape.
More immediately, many of Scotland’s rivers are getting warmer, some approaching the lethal limit for young salmon, so these fish are crying out for the trees that once shaded and nourished them. The roots of trees like alder and willow, which can live in the water, protect fish from the sun and provide hidey-holes during high flow events. Tree roots help stabilise riverbanks and woody structures like fallen trees in the river, create deep pools and riffles providing salmon with the structurally diverse riverbeds they favour. A lack of overhanging trees also reduces insect numbers which in turn, means less food falling from branches into the mouths of hungry fish.
For people inspired by your work, how would you suggest they get involved?
We normally recommend 3 actions:
WILD YOUR SPACE: It’s easy to imagine rewilding at a landscape scale but this is a journey that offers space for everyone. Parks, gardens and public spaces can all make a valuable contribution to a landscape rich in nature and passionate individuals and communities are already working together to create more space for bats, bees and butterflies. Everyone can get involved.
MAKE SOME NOISE: Rewilding is as much a change in mindset as it is a physical change to the land or sea, so it’s good to talk. Most people don’t realise that Scotland has become a nature-depleted nation. Talk to family, friends and work colleagues about the potential of a rewilded Scotland for nature, climate and people. Encourage them to join our Big Picture community.
PUT YOUR MONEY TO WORK: There are many ways to invest in rewilding. You can support businesses such as local farms that are working to restore wildlife, or nature tourism operators who donate part of their revenues to rewilding. And of course, you can help make more rewilding happen by supporting organisations like SCOTLAND: The Big Picture.
A number of previously locally extinct mammals in the Sturt National Park, New South Wales, are now thriving in their feral-free zones, and researchers are amazed by how quickly they have repopulated. With the exclusion of feral cats from enclosures, mulgaras, bilbies and Shark Bay bandicoots have all seen population increases since their translocations. There are also plans to reintroduce another species this year, the golden bandicoot. While this is promising news, ANU ecologist professor David Lindenmayer stated that, while the feral-free zones are helping to conserve animals, both state and federal governments need to do more, including increasing funding and ensuring collaboration between scientists, conservation groups and politicians.
A new report from IPPC warns that many of the impacts of global warming are now “irreversible”. Four months on from COP26, this is the second of three reviews from the world’s foremost body of climate researchers, and looks at the causes, impacts and solutions of climate change. It shows that climate change is impacting humans and other species far worse than previously indicated, with more than 40% of the world’s population “highly vulnerable” to climate. However, authors of the report say that there is still a small amount of time left to avoid the very worst.
Countryside Management Association (CMA) is the largest organisation in England, Wales and Northern Ireland that supports the work of conservation, access and recreation professionals in the natural greenspace and countryside sector. They also have close ties to the Scottish Countryside Rangers Association (SCRA), Scotland’s own association.
Through networking, training and continuing professional development, CMA supports and champions the development of staff, students and volunteers that are involved in the management, interpretation and public enjoyment of natural greenspaces and the countryside. They promote the value and importance of these areas and their management to the general public, government and other organisations, while also providing organisations who are involved in management with helpful and relevant information.
Last year, the CMA ran a photo competition celebrating the work of professionals in the field and shared inspirational photos of staff and volunteers undertaking work to protect, enhance and interpret these important areas. Participants were encouraged to submit images of work involving anything from habitat management, estate work, and wildlife survey and monitoring to leading events and school visits, and engaging with visitors and volunteers. The competition ran from May 2021 to 7th January 2022. We teamed up with CMA to offer some fantastic prizes: a £100 voucher for first prize and £50 vouchers for two runners-up.
Results
Winner: Robert Ballard
The winning entry was taken by Robert Ballard, a ranger at Stover Country Park near Newton Abbot in Devon. His black and white image is a portrait of several volunteers undertaking some pond maintenance. Ponds and lakes are important habitats, supporting a wide range of species. Maintaining and enhancing them has a number of ecological benefits, including increasing wildlife diversity, improving water quality, reducing pond edge or lake shoreline erosion and creating better habitats for aquatic species.
First runner up: Jo Maddox
First runner up was Jo Maddox’s image of conservation work with a city background. CMA liked this image as they are currently seeking to promote and represent greater diversity in their membership, and to highlight urban greenspace management in particular. Urban green spaces, such as gardens, parks and woodlands, provide a vital habitat for wildlife, as well as numerous benefits to people living in urban areas. The management of these areas can help to improve and maintain ecosystem health and biodiversity.
Second runner up: Aam Hersey
Second runner up was Aam Hersey’s socially distanced hedge workers, which CMA thought was of the moment. Hedgerows are dynamic and invaluable habitats, providing food, shelter and breeding sites for species such as yellowhammers, great tits and dunnocks. Hedgerows are made up of a wide range of flora groups, often thought as different layers, including the shrub layer, tree layer, base, margin and ditch. Woody species like hawthorn, blackthorn and hazel make up the tree layer. Smaller woody species, shrubs and climbers, for example bramble, honeysuckle and ivy, are part of the shrub layer, which can also include young trees. The base, margin or ditch parts of a hedgerow can be bare ground, grass or be occupied by wildflowers such as herb robert, wood sage and red campion or thick herbaceous vegetation like cow parsley and common hogweed. Each of these components can support different wildlife, therefore hedgerow management is vital to maintain and promote this biodiversity.
Countryside Management Association
For more information on Countryside Management Assocation, please visit https://countrysidemanagement.org.uk/. Here you will find information on membership, training and events.
Tree surgeons in Barcombe save endangered bird’s habitat. The company tasked with trimming treetops at Barcombe’s disused railway station in East Sussex worked with Barcombe Community Wildlife Group to help maintain the important breeding ground for endangered nightingales. The tree surgeons enhanced the habitat for nightingales and the insects they feed upon along the 33,000-volt 3km route, while still maintaining the power network. The trees and surrounding vegetation were recycled into woodchip mulch to use in the soil, and wood stacks were also made for the area to encourage wildlife.
Grey wolves have had their federal protections restored across much of the US. In 2020, the U.S Fish and Wildlife Service (USFWS) decided to delist wolves from the Endangered Species Act. However, it was suggested by wolf advocates that the USFWS failed to show that wolf populations could be sustainably managed by states in the Midwest and parts of the West without federal protection. A US District Judge stated that the USFWS had not considered species-wide recovery and instead focused on individual recovered populations, such as in the Northern Rockies. Thus, he ruled to immediately restore federal protection to wolves in the Midwest and parts of the West.
Paignton Zoo is freezing the DNA of endangered animals in hopes to save them from extinction. In a project called “Noah’s Ark of DNA”, the zoo has frozen samples from 82 species, including mouse deer, Humboldt penguins and panther chameleons, with the aim of collecting samples from hundreds of the world’s 40,000 endangered species. This is one of several DNA preservation projects in the UK, acting as a potential safeguard for many species.
A study has found that air pollution makes it tough for pollinators to stop and smell the flowers. Researchers have found that common, ground-level air pollutants react with floral scents, leading to reduced pollination. The presence of nitrogen oxides and ozone resulted in up to 90% fewer flower visits, as well as one-third less pollination than in a smog-free field. The concentrations of pollutants used in the study were less than half the average levels of air pollutants considered safe under US law.
Invasive non-native species cost the UK approximately £122 million per year and are a huge driver of biodiversity decline worldwide. There are a surprising number of non-native reptile and amphibian species in the UK, from non-breeding released pet terrapins to established populations of midwife toads, although the impact of some of these species on our native wildlife is not yet fully understood.
The first part of the 2022 Herpetofauna Workers Meeting included a number of talks that discussed the latest research on introduced reptile and amphibian species in the UK, including the Aesculapian Snake in Wales and the Alpine Newt in Northern Ireland. We were pleased to be able to attend and take part in this event again this year, and below is summary of some of the fascinating talks from what was an interesting and informative afternoon.
The Aesculapian Snake
The Aesculapian Snake Zamenis longissimus is a non-venomous species found across southern and central Europe, with relic populations in northern Europe. Although not native to the UK, there are two known introduced populations, one on the grounds of the Welsh Mountain Zoo in Colwyn Bay, Wales, and another along Regents Canal in London. There is also a possible third population in Bridgend in South Wales, but this is unconfirmed as of yet. Tom Major from the University of Bangor is using radio telemetry to study the population at Colwyn Bay to understand how this species is surviving, and he has gained some incredible insights into the ecology of the Aesculapian Snake over the past year.
While tracking nine adult individuals he found that on average the snakes travel the distance of approximately three and a half rugby pitches, and tend to visit one particular place where they stay for roughly four days before setting off again. This seemed to be anywhere that was warm and dry, from a chapel roof to a compost heap. By the end of the tracking period four individuals were still alive. Buzzards, stoats and cars were the reasons behind a few of the deaths, but one interesting cause was cannibalism – one tracked snake was recorded being eaten by another tracked individual, the first known occurrence of this behaviour in this species.
Turtle Tally
Reptiles and amphibians are becoming increasingly popular pets, but a lack of knowledge of their complicated care requirements or an unexpected change in an owner’s circumstances, amongst other reasons, can lead to the intentional release of these exotic animals into the wild. In order to gain an understanding of the distribution and impact of released pet terrapins in the UK in particular, Turtle Tally UK is a nationwide citizen science project that calls for the general public to submit their own terrapin sightings and photos. During her talk, Turtle Tally project lead Suzie Simpson shared some of the findings since the project began in 2019. Each year since has seen an increase in the number of sightings submitted, and hotspots have become apparent in London, Cardiff, Swansea and Liverpool. Yellow-bellied and Red-eared Slider were amongst the most frequently recorded species, and generally only one individual was recorded per sighting.
Red-Eared Slider by Jim, the Photographer via Flickr
When they are out of water, terrapins are usually spotted on logs, rocks and even litter – any raised platform in a water body that they can use for basking. This also includes the nests of waterbirds, but so far there has been no evidence that these terrapins show signs of aggression to waterbirds, or that they predate on chicks. Some species, such as snappers and soft shells, would be more of a concern, however, and the Turtle Tally UK project aims to continue to collect data to further our understanding about the impacts of released pet terrapins on native wildlife. Egg laying has been observed on occasion, but due to the UK’s cooler climate, reproduction is very rarely successful. However climate change could result in more suitable conditions for breeding in the future.
The Alpine Newt in Northern Ireland
The Smooth Newt is Ireland’s only native species of newt and, with its distinctive orange belly and spotted pattern, it is easily recognisable. In September 2020, a strange looking newt was found in Northern Ireland during a bat survey. With a similarly orange belly, but without the spotted markings on its underside and darker in colour, this particular individual did not match the description of a Smooth Newt. It was soon confirmed that this was an Alpine Newt, a species found in Europe but not native to the UK. The discovery of this species is a particular concern as the Alpine Newt is a known vector of chytrid fungus. Rob Gondola, Ryan Boyle and Éinne Ó Cathasaigh provided an update of the consequent Alpine Newt surveys that took place during the following summer in 2021. Thankfully, all the swabs that were taken to test for diseases have come back negative, and they were able to determine the presence of two established populations. Further surveys and testing are hoped to continue in 2022.
There were a number of other talks throughout the conference, from the ongoing study of midwife toads in the UK (another non-native species that was introduced over 100 years ago) to the impact of climate change on UK herpetofauna. This was an enlightening and fascinating afternoon and we look forward to Part 2 of the 2022 Herpetofauna Workers Meeting later on in the year. The date and location of the event will be confirmed at a future date, but any details will be made available on the ARC or ARG UK website. A recording of Part 1 will also be made available – keep an eye on the ARC website for further details.
River pollution is a significant issue in the UK; many rivers are contaminated with sewage, agricultural and road run-off, microplastics and litter. One council is now attempting to protect one river from this by looking to grant it the ‘Freedom of the City’, usually granted to people and organisations to recognise their contributions to a city. Norwich City Council hopes that this honorary title, in combination with other new measures, such as developing planning policies to protect biodiversity, will protect River Wensum from pollution and invasive species. The council will also be asking Anglian Water for evidence on what is being done to prevent sewage spills.
A new leafhopper has been discovered on a student field trip to Kibale National Park, in west Uganda. Dr Alvin Helden of Anglia Ruskin University, Cambridge named the insect Phlogis kibalensis and said it’s from an “incredibly rare” group of leafhoppers, whose “biology remains almost completely unknown”. The last recorded sighting of a species from the Phlogis genus was in the Central African Republic more than 50 years ago, in 1969.
After the devastating bushfires between 2019 and 2020, some koala populations in Australia were on the brink of extinction. Now, the Australian federal government has committed a further $50 million for the next four years to aid koala population recovery, bringing the total federal investment to $74 million since 2019. This funding will also go towards habitat and health protection projects and extending the national koala monitoring program.
A new species of angel shark (Squatina mapama) has been identified in the Central American Caribbean. Angel sharks are flat-bodied, bottom-dwelling species that resemble stingrays. The species was identified through genetic analysis, as it’s a cryptic shark species: they’re morphologically indistinguishable from one or more other Squatina species. S. mapama, whose suggested common name is the ‘small-crested angel shark’, is the fourth new Squatina species to be identified in the last decade.
Foulness Point saltmarsh by Jeremy Halls via Flickr
Saltmarsh, the next habitat in our NHBS Introduction to Habitats series, is an area of the extreme upper shore of sheltered coasts that is inundated with seawater periodically during high tides. However, saltmarshes can also occur further inland, such as along tidal rivers. These habitats are usually angiosperm-dominated areas of vegetation that can develop on a variety of sediment types, including sand and mudflats. They often display striking vegetation zonation patterns across elevational gradients, relating to the degree or frequency of immersion in seawater. This means that, usually, more salt-tolerant species (halophytes) will be found lower down the shore on the seaward side, while less tolerant species would be more likely situated further up on the landward side. These zones are broadly referred to as low marsh and high marsh, but can be further split into an initial intertidal sand- or mudflat, a pioneer zone, lower marsh, middle marsh and the upper marsh zone. These most tolerant species are usually the pioneer species, growing in mud- or sandflats – this marks the beginning of ecological succession in saltmarshes; these plants stabillise the substrate, and add oxygen and other nutrients to the saltmarsh, allowing other plants to establish.
This is a generally well-studied habitat, which is fully classified by the UK National Vegetation Classifications, with 26 types defined. Saltmarshes are made up of a network of creeks and pans (pools), creating sections of land and water. These creeks are developed by the growth of pioneer plant species that grow on raised areas. This concentrates any water flow into channels, which deepen to form creeks as the saltmarsh develops. These areas can be very productive habitats, as the muddy channels can contain sediment rich in decaying matter, supporting a wide diversity of species such as crabs, shrimps and snails, providing food for wading birds and other predators.
What species can you find here?
Flora
Saltmarsh grass (Puccinellia sp.)
Reflexed Saltmarsh-grass – Puccinellia distans subsp. distans by Gertjan van Noord via Flickr
Puccinellia, also known as saltgrass, is a genus of grass that grows in wet environments, often in saline conditions. Some of the saltmarsh grasses within this genus, such as common saltmarsh-grass (Puccinellia maritima), can dominate saltmarsh plant communities, creating dense tufts of hummocks. They can also often be found in pioneer communities, such as in recently disturbed or forming areas of saltmarsh. Some species can grow to quite a height, some between 60cm and 80cm, and provide a refuge for many different animal species.
This flowering plant, also known as herbaceous seepweed, is a yellow-green shrub with succulent leaves and green flowers. It grows in aquatic, terrestrial and wetland habitats, but is mainly found in salt marshes and along seashores, reaching up to about 35cm in height. It’s an important habitat-building species, as it captures mud and other sediment, and stabilises the saltmarsh.
Also known as Tripolium pannonicum, Aster pannonicus or seashore aster, this flowering plant is mainly confined to saltmarshes and estuaries, although it’s occasionally found on cliffs and inland salt works. Sea asters are a short-lived species that can form dense patches. They’re also known as Michaelmas daisies, as their late flowering period is between July and October. Thus, they’re an important source of nectar for several late butterfly species, such as the red admiral.
There are several different species with the common name sea purslane, but this species is a greyish-green shrub found in salt marshes and coastal dunes, usually flooded at high tide. They’re evergreen and contain important nutrients such as zinc and iron. This species can also be used as a bioindicator and biomonitor for mercury contamination in saltmarshes, as it accumulates in the roots and (at lower levels) in the leaves.
This species also has several botanical and common synonyms, including Obione portulacoides, Atriplex portulacoides, purslane orach and lesser shrubby orach.
Fauna
Saltmarshes are important breeding grounds for birds, such as waders and waterfowl, and feeding grounds for overwintering or migrant birds, including wheatear (Oenanthe oenanthe), redstart (Phoenicurus phoenicurus) and goldcrest (Regulus regulus). They also provide nursery sites for many fish species and support a large number of invertebrates.
The variety of habitats and conditions within saltmarshes supports a diverse range of invertebrates, including the saltmarsh plume moth. This distinctive species is found in saltmarshes in the south and east of England, with its larvae feeding on species such as sea-lavender (Limonium vulgare) and rock sea-lavender (Limonium binervosum). They feed on the underside of the leaves, hibernating close to the base of the plant until it can restart feeding in spring. Invertebrate species can be used as indicator species for the level of grazing a saltmarsh has undergone. For example, Agdistis bennetii is an indicator species for ungrazed saltmarshes, as they show a significant preference for these areas and are, therefore, more likely to be found in higher numbers than in grazed areas. This is most likely due to the larvae’s reliance on only Limonium species as food plants, which may be reduced or removed with grazing.
Three-spined stickleback by Gilles San Martin via Flickr
The three-spined stickleback is a small predatory fish that inhabits fresh, salt and brackish water and is very tolerant of changes in salinity. With a preference for slow-moving water with areas of vegetation, it can often be found in ponds, lakes, ditches and marshes. These fish have a brown back with silverish sides and belly. As their name suggests, they have three spines on their back. Males develop bright green flanks and a red throat and belly during spring (as pictured). They hunt invertebrates, including worms, crustaceans, insect larvae and small snails. They’re also prey for several species, including larger fish, such as trout, pike and perch, and birds, such as herons and kingfishers. Eggs, fry and juveniles are also prey for macroinvertebrates, such as dragonfly naiads.
Shore crabs are found along all shores of Britain and Ireland and inhabit a wide variety of shoreline habitats, from the intertidal zome down to a depth of 60m. They’re especially abundant in salt marshes and estuaries, feeding on algae, plants, arthropods, annelids (worms), molluscs and carrion. They’re also prey for some predatory fish and birds, including gulls, cormorants and certain duck species. Herbivory by certain crab species is thought to be impacting saltmarshes in certain areas. For example, bank die-offs of cordgrass species (Spartina spp.) in the saltmarshes of Cape Cod, Massachusetts has been attributed to the native purple marsh crab (Sesarma reticulatum), as dense populations are leading to intense grazing. Other crabs, however, such as the tunnelling mud crab (Helice crassa) found in New Zealand, are thought to be ecosystem engineers, as their burrows help to transport dissolved oxygen into the surrounding anoxic sediments, helping to promote nitrogen cycling bacteria.
Ragworm (Hediste diversicolor)
Ragworm by Dr Mary Gillham Archive Project via Flickr
Polychaete worms, also known as bristle worms, are a class of annelid worms that are generally found in marine environments. These species have pairs of fleshy protrusions on each segment of their body, resembling legs. Ragworms live in burrows and are widespread and common, often found in coastal or estuarine intertidal zones. They’re a key food source for many species of birds and fish, such as pied avocet (Recurvirostra avosetta), curlew (Numenius arquata), bar-tailed godwit (Limosa lapponica), grey plover (Pluvialis squatarola), common sole (Solea solea) and European plaice (Pleuronectes platessa). These polychaetes have also been found to have deleterious effects on saltmarsh establishment, as well as seagrass meadows. This is thought to be due to ragworms pulling the leaves of cordgrass (Spartina anglica) into their burrows to feed while their burrowing activities is thought to reduce establishment rates due to its disturbance of the substrate.
This small, spiral-shelled snail is found along the British and Irish coastline. It is typically found in muddy sand, estuaries and saltmarshes, although it also occurs in lagoons and seagrass beds. Also referred to as Peringia ulvae or the laver spire shell, this species is most common in the upper half of the intertidal zone, feeding on detritus, microflora and seaweeds. They can be quite abundant across saltmarshes, therefore providing a major food source for multiple predators, including flatfish, such as common dab (Limanda limanda), and overwintering waterfowl, such as shelducks (Tadorna tadorna).
Overwintering birds
Bar-tailed godwit (Limosa lapponica) by Laurie Boyle via Flickr
Saltmarshes are key habitats for many ducks, geese and waders, including the bar-tailed godwit (Limosa lapponica). While some non-breeding individuals can be seen in the UK in summer, the highest numbers generally occur between November and February. They use their long bills and legs to pick their way through estuaries, mudflats, sandy shores, saltmarshes and other wetland habitats, mainly eating worms, shellfish, marine snails and shrimps. For more information on the other birds that utilise these habitats, check out our identification guides on UK ducks, geese and waders.
Several mammal and reptile species also utilise saltmarshes, such as Sika deer, adders, otters and stoats. Check out our identification guides for UK Deer, Reptile and Mustelid species for more detailed information about these.
Threats
The main threats to multiple coastal habitats are erosion, pollution, climate change and development. Sea level rise, combined with development, can cause a coastal squeeze – where saltmarsh habitats are unable to ‘move’ in response to changing tide levels, therefore they’re ‘squeezed’ between the rising sea and developed areas, such as where coastal defences have been built. Many coastal habitats are low-lying and are therefore vulnerable to flooding and are where flood defences are most likely to be placed. Aside from contributing to the coastal squeeze, this changes the relationship between the land and the sea, impeding natural inundation and sediment supply and the dynamics necessary to maintain the saltmarsh habitats.
Erosion from wave action, adverse weather, disturbance, farming and grazing can lead to a reduction in stabilising plants and the rich substrate to be washed away. This reduces the habitats ability to support its diverse wildlife and reduces its suitability as a breeding ground for birds. However, carefully managed, low-intensity grazing can maintain saltmarshes, as it increases vegetation patchiness, reduces succession by woody species and, therefore, increases biodiversity.
Development, such as urban development, ports, harbours and land-claim for agriculture and industry, can threaten these habitats, although this is far less common now. Other threats include pollution, through run-off, litter, oil, heavy metals, air pollution and plastic pollution; invasive species, such as Spartina anglica (cordgrass), which can outcompete native plant species and dominate habitats; and overfishing, which can reduce top predators, leading to a collapse in saltmarsh ecosystems.
Hopes for the future
Protecting the remaining saltmarsh habitats, as well as restoring and creating new habitat areas, is an important part of conserving and increasing our biodiversity. Conservation often involves livestock grazing, site management, conservation designations, strict development planning policies, scientifically informed fishing quotas and public campaigns for litter picking, personal responsibility and reducing foot traffic on degraded areas. Restoration efforts usually focus on removing sea defences to restore the natural tidal influences such as inundation, removing invasive species and planting pioneer species to aid the return of natural saltmarsh communities. However, habitat restoration is a difficult and expensive process, and it can take many years to establish. They also may not always be successful, therefore the monitoring and study of saltmarshes are often a key part of restoration projects.
Areas of significance
Barnaby’s Sands and Burrows Marsh Nature Reserve, in Lancashire, which contains an extensive area of ungrazed saltmarsh.
Welwick Saltmarsh, East Riding of Yorkshire, is a sizable area of saltmarsh habitat on the bank of the River Humber, which hosts thousands of wading birds, as well as raptors and owls.
South Efford Marsh, a nature reserve in Devon, includes a patchwork of saltmarshes and grazing fields next to the River Avon.
Rye Harbour Nature Reserve, East Sussex, consists of a mosaic of coastal habitats including saltmarshes, shingle ridges, scrub and woodland.
Fingringhoe Wick, Essex, is a Site of Special Scientific Interest that hosts up to 200 species of birds and 350 species of flowering plants.
West Williamston, is a reserve in Wales made up of tidal creeks, saltmarsh, muddy shores, limestone rock outcrops and woodland. This site is frequented by a large number of waders and waterfowl, including little grebe, shelduck and curlew, as well as other birds such as tawny owl and wren.
Solway Firth is mostly tidal rivers, estuaries, mud and sand flats and lagoons, but there are also salt marshes, salt pastures and steppes. The saltmarshes of Solway Firth stretch along the coast of north Cumbria as well as crossing the border into Scotland. Over 70% of Scottish saltmarshes are within SSSIs.
Loss of animal biodiversity is impacting the survivability of some plants. Species that rely on animal-facilitated dispersal are unable to keep up with climate change as they cannot disperse their seeds far enough to shift their geographic ranges, due to the decline in biodiversity of birds and mammals. Published in Science, a new study has shown that 60% fewer seeds are being dispersed far enough to reach newly suitable habitats, with North America, Europe, South America and Australia the most affected.
Norway has blown up a dam that blocked the Tromsa River for more than 100 years to free up migratory routes for fish. The dam has not been used for over 50 years and the river, which feeds into Norway’s biggest lake, will allow fish in the area to thrive, including grayling, Alpine bullhead and common minnows. Prior to this, the fish were only able to live and spawn in 950 metres of the river. Now that the dam has been removed, these species will be able to swim 10km upriver.
A new study suggests that the sixth mass extinction is currently underway. The planet has undergone five major extinction events but, according to the study published in Biological Reviews, the current one is entirely caused by human activities. Since the year 1500, between 7.5% and 13% of 2 million known species could have already been lost, with drastically increasing rates of species extinctions and declining abundances. However, a bias towards evaluating birds and mammals and an under-reporting of other fauna such as invertebrates may be leading to many denials that the current rate of species die-offs amounts to a mass extinction.
Rewilding has remained very much in vogue over the past 12 months: a wealth of new initiatives and enterprises have emerged, ‘celebrity rewilders’ have made headlines and, most significantly, Defra has announced recently that one part of the new, restructured farm-subsidy system in England will incentivise a switch from agriculture to nature restoration on large landholdings. With momentum only set to build, discussion of the direction of travel, and opportunities and challenges for rewilding remains as important as ever – the ‘Wilding for Conservation’ series, launched in British Wildlife at the start of 2021, aims to provide a forum for that discussion. Here, we revisit the varied topics covered in the series’ first year and look ahead to articles coming up in 2022 and beyond.
Wilding for Conservation, edited by Rob Fuller, began in the February 2021 issue of British Wildlife with an editorial explaining the aims of the series, including to ‘explore the many facets of rewilding as they relate to conservation in Britain’ and ‘bring ideas contained within the expanding scientific and cultural literature to a wider audience, while providing examples of what is happening on the ground in the UK and elsewhere’.
In the May 2021 issue, Jonathan Spencer explored the economics of rewilding, offering a brief history of how industry first maintained, and then later destroyed, high-nature-value habitats, and explaining how the emergence of natural capital approaches and changes to farm subsidies could present new financial opportunities for rewilding enterprises.
In June, Keith Kirby, described European strict forest reserves – protected woodlands left to develop with minimal intervention – and outlined how these might provide lessons for rewilding in British forests.
In the November issue, Hugh Webster reviewed the ability of large carnivores, including wolf and lynx, to regulate populations of other species, and cautioned against building the case for reintroduction of apex predators on their potential ecological benefits, which may fail to materialise.
Wilding for Conservation will continue through 2022 and beyond with articles on a range of topics, including a landscape-history perspective on the limits of rewilding, the reality of passive rewilding in established woodland, the roles of rewilding in carbon storage and mitigating the impacts of climate change on wildlife, case studies on the New Forest and Southern Uplands of Scotland, and much more. And alongside the series, British Wildlife will continue to bring readers the best of natural history and species conservation, and the most important developments in environmental policy.
British Wildlife is a subscription-only magazine which has been published by NHBS since 2016. Annual subscriptions, starting from just £40, can be taken out online, by email (info@britishwildlife.com) or by phone (01803 467166). Individual back issues of British Wildlife are available to buy from the NHBS website.
