Links of interest for

Wales : Skomer


The majority of the Welsh islands are now managed primarily for their conservation interest. Most of the larger Pembrokeshire islands, with the exception of Caldey, were declared Sites of Special Scientific Interest (SSSI) in 1954, and in North Wales, all the larger islands, with the exception of the St. Tudwal’s Islands, were declared SSSIs in 1957, whilst the island of Flat Holm in the Severn Estuary was declared an SSSI in 1972. Most were notified because of their important seabird populations, but in many cases their maritime vegetation was also considered an important factor and several of the larger islands qualify as SSSI on botanical grounds alone. Skomer and Bardsey have since been declared National Nature Reserves (NNRs), and several islands have non-statutory designations – Cardigan, Skomer and Skokholm, represent Wildlife Trust Reserves, and Ramsey, Grassholm and the Skerries are all Royal Society for the Protection of Birds (RSPB) Reserves.

For the purposes of this case study we are concentrating on Skomer. For such a small island – one and a half miles long and one mile wide – Skomer is a real big hitter. An NNR since 1959, it is also a SSSI; was designated a European Special Protection Area (SPA) for its breeding seabirds in 1982; is listed in the Geological Conservation Review and lies in the Pembrokeshire Marine Special Area of Conservation (SAC). The surrounding seas, including much of the area around the Marloes peninsula, were designated as a Marine Nature Reserve (MNR) in 1990 to become Wales’ first and only conservation area of this kind. Further, in 2009, it was announced Skomer would be the first marine site in Wales to be protected by new assembly government powers. It will become a Marine Conservation Zone aimed at preserving important habitats and species and eventually replenishing fish stocks. Finally, the remains of prehistoric houses, as well as a stone circle and standing stone, have resulted in much of this tiny speck of rock off the Pembrokeshire coast also being scheduled as an Ancient Monument.

Skomer  is managed by the Wildlife Trust of South and West Wales under a lease from the owners, the Countryside Council for Wales, and is open to visitors from April to October. The island is also an ideal place for field trips for both formal and informal learning opportunities with a range of educational resources, facilities and support available for teachers, school pupils and students. The warden and assistant warden live on the island for nine months of the year, looking after visitors, surveying and monitoring wildlife populations, and maintaining the island’s accommodation, information and research centre, office and library.

Renewable Energy & Eco Housing

Until 2005 the only electricity on the island came from two small petrol driven generators, all lighting and cooking was powered by bottled gas and there was very limited water available in the few buildings and certainly no showers. All this changed in 2008 with a major renovation project that won the Wildlife Trust a RICS Wales sustainability award. The aims of the £3.5 million Skomer Island Heritage Experience Project were to conserve and enhance the heritage of the island and improve the quality of the visitor experience through the provision of better interpretation and accommodation facilities.

Lockley Lodge on the mainland is the gateway to the island and space within the original building was limited. The larger and much improved lodge now has interactive interpretation showing how the island has inspired people over the years. Live pictures are now beamed through to Lockley Lodge from Skomer thus providing an alternative experience to actually travelling to the island when weather prevents sailing and for those with limited mobility. A nearby old Coastguard Lookout was also restored and is ideal for setting Skomer into the geographical context of her sister islands of Skokholm, Grassholm and Ramsey.

At the heart of the island itself lies the old farmhouse complex, once a thriving agricultural unit which supported a number of families. These derelict buildings provided the perfect opportunity to meet the accommodation requirements of the assistant wardens, volunteers, researchers and overnight guests who wish to watch the night-time spectacle of the hundreds of thousands of Manx shearwaters returning to their burrows. To this end, the farmhouse buildings were renovated and restored sympathetically and in line with guidance from Cadw, the Welsh Assembly Government’s historic environment division. The old farmhouse was made safe, capped and kept as a managed ruin. An internal roof was put on in two of the rooms that can now be used for shelter. One also has picnic tables and interpretation panels about the past and future of the island.

The Project also rebuilt the assistant warden’s and the volunteers’ accommodation, greatly improving facilities. A visitor centre was also provided at the end of the Old Barn taking the opportunity to significantly enhance the quality of interpretation provided to ensure the visitor experience is maximised. In addition, the separate accommodation for the warden was no longer fit for its purpose, so the old building was demolished and replaced by an island office situated in the same location overlooking the two landing points. Also within this new building are the library, a laboratory and study rooms for researchers.

An array of photovoltaic panels to generate electricity was installed behind the farm buildings and also on the roof, along with solar panels for hot water. Additional solar panels are on the roof of the visitors’ accommodation. There is a battery bank to store electricity enabling the island to have electric lighting and run other electrical appliances. There are also three small wind turbines that generate electricity when day lengths and the power of the sun are less. In the winter when there is no one in residence and no other calls on the power system, small, low energy, warming devices in many of the rooms use any excess energy produced to maintain the temperature in the buildings above that of the outside, keeping the buildings free from damp.

All construction works on the island were completed to the highest standards. To ensure that none of these works jeopardised the conservation work being carried out and did not disturb the delicate ecology on the island, all the building materials were quarantined and had to be baited against rats prior to being moved by barge to the island thus eliminating the risk of pest species being brought to the island. Although the restoration of the buildings aimed to produce robust, energy efficient buildings with a small eco-footprint, the use of traditional materials was incorporated wherever possible.

Waste Minimisation & Recycling

There is very careful management of all waste on the island. All materials that can be composted are, and there are special bins in all the kitchens. Equally, all combustible materials are separated out and burnt on the island in tightly controlled conditions. All other waste materials like tins, glass, plastics etc are removed and returned to the mainland for recycling.

Water Management & Security

Having electricity on the island enables the easy pumping and movement of water to and around the buildings. Previously a header tank was supplied by water drawn from a spring by wind pump. There are plentiful supplies of water on Skomer from a number of springs but these sometimes run dry, or cannot meet the daily extraction rate, so storage of water is important. At the old farmhouse water is pumped from North Pond to a header tank on the knoll behind the complex, which then feeds by gravity a large tank in the garden. Cold water is then treated and supplied to tanks in the buildings with some being heated by the solar panels before being pumped back into the complex. There are no baths on the island but there is enough water to supply kitchen and bathroom sinks, showers and flushing toilets in all the residential buildings. Once used the wastewater drains away from the complex and is collected and put through a simple sealed treatment system. Here any solid materials are broken down and eventually, following settlement and biological treatment, clean water is returned back into the island’s soils.

Prior to the renovation project, one of the major uses of water on the island was the public toilets. With up to 250 people a day this resulted in many gallons of water simply being flushed away. New composting toilets have now been installed at the end of the Old Barn and this means that even with the new facilities for the residential visitors, the island is saving water overall. These toilets work on a self contained system by which waste breaks down naturally through microbial action, helped by the addition of small amounts of sawdust or wood shavings and biological activator. A positive airflow down through the system means that there are no bad smells, but it is important to keep the toilet lids down when not in use. At the end of the season the compost can be dug out and used to enhance the soil in small vegetable gardens maintained by island staff and volunteers.

Extensive Agriculture & Organic Food Production

The history of the Welsh islands was early influenced by the development of Neolithic culture in Britain. During this period man turned from being a hunter gatherer to a pastoralist and started to open up areas for agriculture at the expense of native wildwood. The period may have had its beginnings as far back as 6000 years BP and no doubt coincides with the removal of woodland from several of the near shore Welsh islands. In fact, there is evidence to suggest that some form of agricultural management may have been practiced on Skomer ever since it became an island, around 12,000 BP.

The main settlement of Skomer can be dated to between 5000 and 2000 BP, and evidence and remains from this period, known as the Iron Age, can be seen all around the island. The remains of huts, fields and cairns (possibly burial cairns) on Skomer are some of the most complete and untouched remains of this period in the whole of Europe, and their extent indicates an Iron Age farming community of up to 200 people. It is known that barley and primitive wheats such as emmer and spelt were cultivated in some of the ancient field systems and the grasslands grazed by cattle, goats and primitive sheep. The latter are thought to have had much in common with modern Dexter and Soay sheep.

Following the Iron Age settlers there is no clear history of habitation until the Middle Ages, when in the 13th century rabbits were introduced to the island. Rabbits were brought by the Normans and were a valuable source of food and fur, their skins being as important as their meat. Many islands were used as Warrens (places where rabbits were kept) at that time, as the rabbits could not escape and equally they could easily be protected from poachers. Initially, they were vital to the people who lived or farmed on Skomer, with Conies (the early name for rabbits) being a major export from the island to local markets. They have become even more important recently as the main grazing animal on the island, maintaining the short vegetation and plant diversity. It seems likely that the early Warreners had a simple homestead in the centre of the island, probably where the old farmhouse complex is today.

The now renovated farmhouse dates from about 1840. The slightly thicker soils in this part of the island, and access to water from North Valley enabled a range of crops to be grown, and large fields were established around the farm with long straight stonewall boundaries. There are records of the farm supporting three families at one stage with cows and sheep grazing the island, as well as horses to help with the heavy work. Cereals were grown and hay crops taken, it would have been a hive of activity at harvest time. Farming was largely abandoned after the outbreak of the First World War in 1914, with a slight revival in the 1930s but then all agriculture on Skomer finally ended in 1950. In 1959 the island was bought for the nation by the Nature Conservancy (the government agency that became the Countryside Council for Wales) and declared one of the country’s first NNRs.


Skomer is reached by boat from Martin’s Haven, a small cove two miles on from Marloes village, which is 12 miles south west of the county town of Haverfordwest. The boat, the Dale Princess, runs between Good Friday or 1 April (whichever is the earlier) to 31 October each year. The 20-minute journey through the tidal currents of Jack Sound can be choppy, with northerly winds and bad weather meaning cancelled crossings – sometimes for days at a time. In good conditions the boat leaves at 10am, 11am and 12am six days a week, returning from 3pm onwards. Visitor numbers are capped at 250 a day, and dogs are forbidden.

Sustainable Tourism & Niche Marketing

As well as day-trippers Skomer also attracts those wishing to become volunteer wardens. Members of the public with an interest in wildlife fill six weekly positions during peak season, and four during September and October. It is an ideal and rewarding holiday for those who like to mix a little nature conservation work with their relaxation. The volunteer wardens’ main duty is to help with the day visitors, manning telescopes and providing information, but if the weather keeps the boat on the mainland there is still plenty to do. Bracken clearance is vital to prevent the network of meandering paths from becoming choked with the dense fern banks that carpet the island.

Conservation work depends on the time of year, but includes performing bird, cetacean and vegetation studies, whether counting whales from a cliff-top, or assessing vegetation growth in an area from which rabbits have been excluded. Other tasks include repairing boardwalks and bird hides, painting buildings, library cataloguing and helping out in the warden’s office. Volunteers get the run of Skomer after visiting hours. Certain research or conservation areas aren’t open to the public, but an interest in a particular facet of conservation work can be accommodated. Areas such as The Neck – an almost-island connected to Skomer by a narrow isthmus – are the perfect place to help the seal researchers check for newborn pups. There is now a Skomer blog  written by the people living and working on the island as well as Facebook group  and Twitter page.

Biodiversity & Protected Areas

There seems little doubt that most of the larger Welsh islands had some form of woodland vegetation when they became separated from the mainland. Supporting evidence comes from the fact that oak woodland/scrub still persists on some isolated stacks off the Pembrokeshire coast, pollen analysis on Bardsey has shown that prior to man’s activities the island supported various tree species including oak, birch, alder, hazel etc, and the presence of certain plants including some fungus species on Skokholm are regarded as evidence of a relic field layer of previous woodland. Moreover, the name Skokholm is believed to mean “wooded island” given to it by Scandinavian invaders in the 9th century. However, this suggests that if Skokholm was conspicuous for its woodland, at that time, then most of the other Welsh islands were probably devoid of woodland. This is certainly understood to be true for Skomer that was probably cleared of its trees during the Neolithic period. Today, it is well known that trees will survive on the Welsh islands. Caldey supports an extensive area of woodland, including sycamore and there has been a small conifer plantation, mainly composed of sitka spruce, on Bardsey since 1973. Elder has been established on Puffin Island since at least 1889 and it is now thought to be one of the largest elder forests in the UK.

In the 1950s, when most of the Welsh islands were declared SSSIs, they often supported extensive areas of rich maritime grasslands and heathlands. The grasslands produced displays of spring colours with the blues of spring squill and pinks and reds of sea thrift and red campion. In autumn, the maritime heaths produced intricate mosaics of yellows and purples, and it was assumed that these vegetation types were self-sustaining and only needed protection from human influence to remain in perpetuity. It was only later discovered that many of them did not represent stable climax communities, but were actually the culmination of many centuries of agricultural management. Important elements of this management included the harvesting of rabbits, bracken and gorse. The cessation of these traditional agricultural practices led to rabbit and bracken infestation on several islands that in turn caused the loss of maritime heathlands and grasslands. The problem was further exacerbated by a massive increase in the seagull population. In addition, several important seabird colonies have been threatened by rats, which were inadvertently introduced to some islands, and in the case of Ramsey, by feral cats. Much conservation management has therefore been directed towards addressing these problems and current strategies for most of the larger island reserves are geared up to restore and thereafter maintain all habitats at their optimum condition and distribution for native species diversity.
The impact of rabbit grazing on the Welsh islands can be assessed by comparing the rabbit free island of Grassholm with the rabbit infested Skokholm where myxomatosis, due to absence of the flea vector, has not had any impact on reducing the population. On Grassholm, in the areas not colonized by gannets, a species poor, red fescue mattress has developed and the normally common sea thrift is absent, whereas in some of the more exposed areas of Skokholm, sea thrift is the dominant species. Also, under moderate grazing pressure plant species diversity in these coastal grasslands tends to be higher since it prevents dominance by any particular species, especially vigorous, tall growing species, and thus permits diminutive, less dominant species to grow which would normally be shaded out. On the other hand, rabbit grazing in inland areas tends to cause a decrease in species diversity due to the abundance of tall and non-resistant species. On rabbit grazed islands, non-resistant species are mostly confined to the inaccessible cliffs and stacks or permanently marshy areas. In fact, by selectively feeding on certain species, rabbits can radically alter an island’s ecology.

Two gull species, the herring gull and the lesser black-backed gull, have undergone massive increases in their population sizes over the past four decades. This has affected most of the Welsh islands, but it has been particularly damaging on Cardigan, Flat Holm, Skomer and Skokholm. Seagulls and other cliff-top, colonial seabirds such as gannets, puffins, shearwaters and razorbills, can have a major impact on island vegetation. This is mainly due to guano deposition and the physical damage caused by trampling and extracting nest material. Guano is very rich in essential plant nutrients compared with mammalian dung and so causes hypertrophication of contaminated soils. Initially, this may stimulate plant growth, but as the nutrient levels increase the soil may eventually become toxic and eventually inimical to all plant life. However, several halophytic species, such as buck’s horn plantain, sea campion, speared-leaved orache, sea mayweed, sea beet, scurveygrass and common sorrel may display luxuriant growth in moderate concentrations. Seabird or ornithocoprophilus vegetation has, not surprisingly, shown a considerable expansion over the past three decades. On the limestone island of Flat Holm, guano deposition made the soil progressively more suitable for nettle, bracken and finally elder. Likewise, an elder climax or plagio-climax community has developed on Puffin Island that is also composed of limestone. In order to lessen the impact of burgeoning gull numbers, control involving raking, pricking or removal of eggs, has been practiced on Skokholm and Flat Holm.

On Skomer, bracken in some cases was found to be advancing at a rate of 2m per year and its spread in the 35 years leading up to 1986 was, on average equivalent to about 3.2ha per year. There are a few areas where bracken cannot colonise, such as aquatic and waterlogged areas, and places exposed to large amounts of salt spray. However, in parts of Skomer it has been advancing into what appear to be very exposed situations. This seems to be related to the fact that cliff-top salt burn of bracken is dependent on summer storms; winter storms apparently have little or no effect on the buried rhizomes. On the other hand, conditions on Skomer are now thought to be unsuitable for the gametophyte generation. Much of the new bracken is therefore derived from vegetative growth. As bracken advances, it normally eliminates the original vegetation due to shading and possible changes in the soil chemistry. As a result, for a short period, bracken becomes mono-dominant. Subsequently, other species gain a foothold beneath the canopy and a relatively stable community develops.

Bracken is now considered to be a problem on all the larger of the Welsh island reserves and major efforts to control the species have been carried out on Flat Holm, Skomer and Skokholm. Indeed, efforts to control bracken on Skokholm can be traced back to at least 1937. The methods vary from cutting with hand-scythes, followed by raking and burning, to the use of forage harvesters and spraying with the herbicide asulox. On Skomer lesser black-backed gulls often nest in small clearings in bracken that they tend to gradually open up, and it has been suggested that they are playing a major role in preventing its spread. Bracken is seen as a species that should be controlled but not eliminated, especially on Skomer where it also forms the principle habitat of the Skomer vole. Other semi-natural habitats on Skomer, such as the inland, sub-maritime grasslands are also deemed important, whereas on Bardsey traditional agricultural habitats such as haymeadows and semi-improved pastures are also regarded as essential.

Rats are omnivorous opportunists that will readily feed on the eggs and chicks of ground nesting birds, and will also kill adult birds. Their activities have severely affected, or possibly even eliminated, certain colonies of seabirds and their control is now seen as a major priority on a number of islands including Puffin and Ramsey. The RSPB, using baited poison, has significantly reduced the rat population on Ramsey, and on Cadigan the Dyfed Wildlife Trust has successfully eliminated them altogether. In addition to rats, Ramsey also has a population of feral cats. These have been preying on both young and adult seabirds including shearwaters, and so the RSBP has been making strenuous efforts to remove them from the island using a live capture technique.

For many years the seabirds on Skomer have been watched by biologists but these studies typically focus on a relatively small number of ringed birds to try to gain an impression how many of them survive from year to year. However, guillemots on the island are at the forefront of a new project. Computers watching the birds are recording key behaviour such as how long they spend at the breeding colony. Researchers hope to gather detailed information about changing behaviours and spot key trends. Seabirds such as guillemots are an indicator species that can give ‘early warnings’ of habitat degradation or other environmental problems. A monitoring system is being created that films nesting birds and then analyses images to work out what the birds are doing, how long they spend at the colony caring for young and how long foraging. Other seabirds on Skomer are now also being studied using the latest technology. Some of the burrows from an estimated 120,000 breeding pairs of Manx shearwaters have been fitted with a tube incorporating an ID tag reader and a weighing scale to find out the weight of fish the birds catch and bring back to their burrow for their young. A local wireless network has been set up to collect data from the different units.

Unlike the rest of the UK, the number of puffins on Skomer has soared in recent years - leaving conservationists baffled. The island currently (2009) has a puffin population of more than 13,500 - up from 10,000 the previous year. Contrastingly, on the Isle of May in Scotland, the largest breeding colony in Britain, numbers fell from 70,000 in 2003 to 41,000 in 2008. On the Farne Islands numbers also dropped by around a third, from 56,000 to 36,000, during the same period. However, scientists do not know why numbers are decreasing. Possible reasons include climate change, that is causing the birds' main food source sandeels to move north to cooler waters. Pollution can also affect numbers and competition from other species such as gulls. In an effort to find out the reason, scientists fitted global positioning system (GPS) technology to a leg ring on some puffins in the Farne Islands this summer to work out where the birds go to feed in the winter, how they get there and how long they stay in different areas. The devices will also provide information on diving behaviour, such as how often they dive and how deep and sea temperatures. When the data is collected from returning puffins the following year it will provide clues to the kind of feeding grounds the birds have been to and therefore the threats they are exposed to.

Grey Seals studies on Skomer began in the mid 1960’s, with the colony being closely monitored since 1973, one of the longest Grey Seal studies in the world. Marking showed that young Grey Seals from the Pembrokeshire colonies are great wanderers they can during their young lives, reach north into Liverpool Bay, south to Devon and Cornwall, to Brittany and even the north coast of Spain, while others crossed to Ireland even as far as Galway Bay on the west coast.

The Skomer Marine Nature Reserve is one of only three marine nature reserves in the UK. The CCW MNR staff team, based at Martin’s Haven monitor the seas around Skomer using many techniques, including diving and underwater photography. Both short term and long term changes and trends can be picked up in this way, and the work on the site is very important in helping us understand the marine environment better, and particularly the impacts of climate change on our seas. For example, further research into local sandeel distribution might help reveal why puffin numbers on Skomer have increased compared to the drops in population recorded at other UK colonies.  

In addition to their biological importance, the Welsh islands also have considerable geological, archaeological and cultural significance. It was with all these different concerns in mind that the Welsh Islands Conference was held in November 1995 to bring together as many people as possible with a long-term interest in the conservation of these islands. The conference proved to be a major success and provided the first step towards developing a more integrated approach to the management of these important islands.