Summary – Talk – Limestone Country

On 9th January 2020 a number of people braved the seasonal weather to assemble in the Dark Island Hotel to hear Robin Sutton’s talk about the Yorkshire Dales. We were treated to a full range of seasons, but on a breezy January night it was good to see a lot of pictures of the dales and their wildlife in summery weather.

            Robin worked in the Dales at Malham Tarn Field Studies Centre for fourteen years, giving him a good opportunity to explore the area and record many aspects of its habitats and species in different seasons. He noted the importance of regularly recording common things, allowing observation of changes over time.

            The Yorkshire Dales lie between the Pennine hills that form the watershed between east and west in northern England, so some rivers flow into the North Sea and some eventually into the Irish Sea. The dales are glacial valleys: the typical U shape with flat bottom and steep sides, cut into the hills which are composed of alternate layers of hard sandstone and limestone, the sandstone on top of the peaks and the layers of limestone increasing in thickness on the lower slopes and valley bottoms. The highest ‘Three Peaks’ are well known: Whernside [possibly  named from the use of sandstone for querns], Ingleborough [the fort of the Angles] and Pen y Ghent [Hill of the Wind]. The limestone has horizontal bedding planes formed as the sediment was laid down, and vertical breaks or joints; while the stone itself is impermeable, water can travel along these joints. In some areas there are expanses of limestone with an uneven but overall bare  level surface broken into segments or  ‘clints’ by deep clefts or ‘grikes’ which follow lines of joints, forming a ‘limestone pavement’. In the clefts, with shelter from winds and grazing animals, vegetation grows, including woodland species; if stock were excluded soils would gradually develop and the whole area become a woodland.

            Robin took us on a circular ramble in the Malham Tarn area, showing different types of vegetation and some typical and some unique species on the way. For instance, Malham Tarn is home to a flightless caddis fly which occurs nowhere else in Britain, but is also known from Estonia! Plants occurring in the area include Bloody Cranesbill, Rock Rose, Birds Foot Trefoil which supports the Common Blue Butterfly, Early Purple Orchids [some of which are white] which attracts queen bees although the orchids produce no nectar. In early summer a lot of the flowers are yellow: Ladies’ Bedstraw, Yellow Rattle, Cowslips; and later in summer blue is more dominanat: Harebell, Small Scabious and Devil’s Bit Scabious and Hard heads, attracting Painted Ladies, Red Admirals and Dark Green Fritillaries, Chequered Skipper and Brown Argus among other things.

            The area has a range of soils from the calcareous on the limestone to more acid where there are areas of boulder clay formed during the glacial period and some acid peaty areas. In the limestone areas there are ‘shake holes’ which have formed when water running down joints in the rock has eroded the rock under the surface until a cavity is formed and at some point the uppermost rock with the topsoil drops down; these can be a hazard to visitors.

            As water is diverted from the surface down sink holes to channels under the rock, dry valleys form, but in very heavy rain the underground channels can be filled and the valleys run again with surface streams. At some time in the past the cliff at Malham Cove was formed, but water very rarely comes over it now: Robin did not see water falling there during his years living there but was told that during Storm Desmond in 2015 so much rain fell that water did come over, forming the highest waterfall in Britain. There are dark areas on the rock face looking like soot. When Charles Kingsley visited the area and saw this it may have inspired elements of his ‘Water Babies’.

            Peaty areas are formed where water loving plants grow in wet areas and gradually accumulate a growth of peaty material which as it rises above the water table supports such plants Lesser Clubmoss, Cotton Grass and Cross leaved Heath, the very pretty Grass of Parnassus and the Birds Eye Primrose which grows only in the north of England.

            There are also areas of woodland with Ash, and expanses of Wild Garlic, Bluebells, Red Campion, and Sweet Cicely, which was brought by the Romans who chewed the stems.

            In Malham Tarn itself there used to be crayfish, which may have been eradicated by a crayfish disease, as there are none now apart from in a very small area of the tarn, close to an area of yew, giving rise to the theory that chemicals from the yew, leaching into the water, may provide some protection to the crayfish in that area of water.

            Robin had all sorts of intriguing little facts about the area, plants and animals, which added to the interest of his talk. His illustrations were excellent.

            The next talk will be: Geese, Peat and Malt Whisky: Islay by Martyn Jamieson on 13th February at the Dark Island Hotel, 7.30pm

Dawn at snowy Malham Tarn ©Robin Sutton
Plants of Malham Tarn ©Robin Sutton

Summary – Talk – The Croft Woodland Project

On Thursday 12th December 2019 a good number of people assembled in the Dark Island Hotel to hear a talk by Viv Halcrow, the Woodland Trust’s Croft Woodland Project Officer for the Western Isles.

The Project started in 2016 in all the crofting counties, and in the Outer Hebrides is funded by the Point and Sandwick Trust, with support from Scottish Forestry and the Scottish Crofters’ Federation. Funding for the scheme is now secure until 2026.

Viv provides advice and practical help, including getting funding for planting schemes. The Outer Hebrides has seen the greatest number of enquiries, with at least 450 since the project began, resulting in more than 90 schemes started, of varying size. By April 2020 just over 100,000 trees should have been planted in over 31 hectares.

Viv went on to list the main reasons for planting trees: to shelter buildings, gardens, livestock or crops; to improve soil by raising deep nutrients nearer the surface and depositing leaf litter; to add variety to the landscape; to provide habitats and food for wildlife; for fuel; and for craft purposes, particularly willow.

Locations need careful consideration; trees won’t grow on deep peat [planting should not be attempted anyway as peat stores carbon] and should not be planted on machair; in between, they will do best when they have some shelter from the immediate topography, and a good depth of reasonably fertile soil (at least a foot – or 30 centimetres).  Water pipes, electricity cables both underground and overhead should be avoided, and sites designated for particular natural features or archaeological remains may not be suitable for planting.

Native species are most appropriate, and ideally of local provenance or as near as possible: grey willow, eared willow, downy birch and alder; and other local species are aspen, hazel, hawthorn, bird cherry, sessile oak and rowan. Non-native trees that will grow are sycamore, which is resistant to salt, other types of willow, lodgepole pine and Sitka spruce. Shrubs with waxy leaves that are resistant to drying in strong winds are escallonia and olearia, which can be grown for shelter round plantations.

Some tree nurseries are now getting under way in Lewis at Leurbost and near Shawbost, and one in the Bays of Harris, growing trees from locally collected seed.

Planting involves design of the scheme, neighbour consultation, fencing (including deer fencing in many places) ground preparation and fertilising. Once the trees are planted they may need protecting against rabbits and, in Uist, voles. Planting at a high density with seedlings just 1 or 1½ metres apart is recommended, and the grants support this density. Ideally a scoop of soil is removed and turned over to provide a low mound with no other plants around the newly planted tree, so no competition for light and nutrients.

Maintenance is essential: weeding, and/or mulching around the trees; replacing trees that fail, topping up fertiliser, repairing fencing if necessary, and checking for browsing damage, including by caterpillars which can defoliate the trees. Mulches should be organic material that will gradually decompose and add to the soil; cardboard, paper and sheep wool are all suitable materials. If there is a long dry spell ideally the trees should be watered if possible; mulches help to retain the moisture in the soil as well as discouraging weed growth.

There are grants available:

  • MORE woods provides a 60% grant for a minimum of 300 native trees, under a twelve year agreement, but this does not include money for labour, fertiliser or fencing.
  • The SRDP Forestry Grant Scheme provides £3600 per hectare for between ¼ and 3 hectares of planting, with an additional allowance for fencing, tree guards or netting, gates and a management grant for five years. This is under a twenty year contract. A CAGS shelterbelt grant is available for fencing and shelterbelts for horticultural businesses or for shelter of livestock.

More information can be found on the Point and Sandwick Trust website where you can see a map of schemes already planted, (one of the largest in Uist being in Grimsay with over 5,000 trees), the Woodland Trust website, or ‘Facebook’ under ‘Western Isles Trees on the Croft’ or get in touch with Viv by e-mail:

House and young woods, Harris

Summary – Talk – The Raptors of Uist and Barra

On Thursday 14th November 2019 the usual room in the Dark Island Hotel used for Curracag talks was filled to capacity for Andrew Stevenson’s talk on our local raptors, a talk organised by Martyn Jamieson for Curracag, but open to anyone interested.

Andrew started by telling us modestly that his talk was based on the work of the Uist Raptor Study Group, one of 13 raptor study groups which cover Scotland, and of which he has been an active  member for a number of years. Even for the most dedicated groups, keeping track of a range of birds with a small membership in some of the challenging terrain we have, especially on the east side of Uist, is very difficult.

He described briefly the range of habitats available to raptors: the extensive hill and moorland, loch systems, machair, offshore islands and cliff, providing a wide range of food sources from various sizes of birds, mammals and carrion. Of the smaller mammals, woodmice, rats and rabbits are present in most of the islands, but field voles are not known in Barra or some of the offshore islands, and though hares were introduced to North Uist in the last century they have not survived, so the range is limited. Likewise, the range of predators is more limited than on the mainland, as we have no foxes or pine martens.

Other factors that affect some of the birds (and their prey) are weather; wet and windy springs and summer can affect nesting birds; and muirburn, when carried out outside the legally permitted  season and not controlled. Human interference is limited.

Andrew then took us through a list of our resident raptors, with comments on each.

Golden Eagle, for which there are about 25 ranges in Uist, taking as prey birds such as red grouse, ducks, sometimes fulmars, geese, and also rats and rabbits; one pair seem to specialise in taking gannets. Recently some eaglets have been found dead or dying from an unknown cause, but not a lack of food sources. Our golden eagles are slightly different from the mainland population; there seems to be very little if any exchange across the Minch.

White-tailed Eagle, which now has 11 ranges in Uist, the result of expansion since their re-introduction to Scotland in the 1970s and 1980s. They take wildfowl, grouse, and herons, and even hedgehog and octopus have been known to feature in the diet!

Uist supports between 40 and 50 breeding female Hen Harriers, a big improvement on the 10 to 15 pairs known in the 1980s, nesting on moorland and foraging over considerable distances, sometimes as much as 11 kilometres. They are not present in Barra as there are no field voles, one of the main prey items. They have recently colonised Lewis despite the absence of voles, feeding mainly on small birds.

Similarly, Short-eared Owls only breed in Uist; between  about 60 and 90 pairs, with a long breeding season, the earliest chicks fledging in mid May while some appear in August. Short-eared owl populations are declining internationally; ours fluctuate although the Uist vole populations don’t seem to crash as they do in other places.

Long-eared Owls breed rarely in North and South Uist, possibly about 10 pairs, but are difficult to find and study as they are nocturnal owls, unlike the short-eared owls which fly during the day and are often seen from the road.

There may be about 95 to 100 pairs of Buzzards, which are mainly on the west side, and will be familiar to most.

Peregrines are limited: in 2002 there were 19 ranges, but now there seem to be fewer, paralleling a decline on the mainland. Prey: waders, seabirds and rock doves are not in short supply.

There are probably 20 to 30 pairs of Merlin, taking passerines and small waders.

And a similar number of Kestrel, living mainly on the east side on Uist. These too are declining nationally.

Sparrowhawk is a recent colonist, arriving about 2001. 10 pairs take advantage of the conifer plantations that are a comparatively recent habitat in Uist, and even sometimes gardens.

Andrew bestowed honorary raptor status on the Raven, which is widespread, 70 to 90 pairs frequenting quarries, trees, disused buildings, mainly in remote areas. A large non-breeding population use different roost sites. Pellet analysis in 1997 showed that their food was mainly rabbit, birds and small mammals.

Though large raptors may take smaller ones: eagles will eat everything; buzzards take short eared owl and hen harrier chicks, but smaller raptors don’t necessarily avoid the larger ones, being, apparently, more concerned about their own food availability.

Andrew also mentioned species that visit occasionally such as snowy owls and honey buzzards.

Summary – Talk – Highland Naturalists

Curracag – the Outer Hebrides Natural History Society – held their first indoor meeting of 2019 in the Dark Island Hotel on 8 January. The speaker was John Love who has been a member since the Society’s inception. Based in South Uist, John was formerly an Area Officer for Uist, Barra and St Kilda with Scottish Natural Heritage, also a former Chairman of Curracag and, for several past issues, editor of their journal Hebridean Naturalist. Appropriately his talk was about Highland Naturalists, tending to focus on the Hebrides with a selection of home-grown individuals and a few other notable characters.

The Hebrides has long been a fertile stamping ground for naturalists from home and ‘abroad’ and John began his talk with Skyeman Martin Martin, a tutor to the Macleods of Dunvegan who visited the remote archipelago of St Kilda back in 1697. His popular book on the voyage was soon followed up with another on subsequent visits to many other Hebridean islands, both Inner and Outer. One has to bear in mind that his travels took place only five years before the Massacre of Glencoe and also before the ill-fated Jacobite Rebellions. Martin wrote how these islands had never before been ‘described till now by any Man who was a Native of the Country’. Indeed he went on to lament how ‘foreigners sailing through the Western Isles have been tempted from the sight of so many hills that seem to be covered all over with heath and faced with high rocks, to imagine the inhabitants, as well as their places of residence, as barbarous; to this opinion their habits, as well as their language, have contributed.’

Being a native Gaelic speaker he was able to glean from his fellow islanders a wealth of folklore, natural history, traditions, customs, cures and remedies that would otherwise now be forgotten. ‘In the course of my Travells,’ he went on, ‘anything that was remarkable fell under my Observations’ . . . ‘the field of Nature is large, and much of it wants still to be cultivated.’

After the ’45, travel through the Highlands and Islands became easier and even the elderly Dr Samuel Johnson was able to journey extensively in 1772. An eminent naturalist of the 19th century was William MacGillivray. Born in Aberdeen but raised in Northton, Harris, MacGillivray later walked all the way to attend university semesters in Aberdeen. He claimed ‘the solitude of nature was my school’ and how he had ‘reaped most advantage from solitary travelling.’ He even walked all the way to London to visit its Natural History Museum and went on to become a museum curator himself first in Edinburgh then assuming the Chair of Natural History back in Aberdeen. MacGillivray wrote many scholarly books and was well known for leading his students ‘to take to the fields and the woods, the mountains and shores, there to examine for themselves the rich profusion of nature.’ Indeed, it was said, he frequently walked ‘the most active of them into a state of limp helplessness’.

John Love himself gained his degree in natural history at Aberdeen where he first encountered the name and exploits of William MacGillivray. William was also an accomplished artist and many of his fine bird paintings are now in the Natural History Museum.

Our speaker went on to highlight other distinguished naturalists who shared a profound interest in the Highlands such as JA Harvie-Brown, Seton Gordon, Robert Atkinson, Frank Fraser Darling and J Morton Boyd – all greatly influencing him as a youngster. On joining the Inverness Bird Club in 1959, he was to meet Seton Gordon himself, Morton Boyd – who would later become his boss in NCC/SNH, George Waterston and Lea MacNally – all eagle enthusiasts. George was then Scottish Director of the RSPB who inspired John to volunteer at the Loch Garten Osprey hide in the summers of 1963/64. Lea MacNally was a stalker/naturalist in Fort Augustus who went on to take some wonderful photos and write several books about Highland wildlife.

Seton Gordon

From his schooldays John was mentored by two birdwatchers in particular. Dr Maeve Rusk was an ophthalmic surgeon at Raigmore Hospital who held regular clinics in the Hebrides. She was president of the local Bird Club, took John on her monthly duck counts and taught him how to mist-net and ring birds. The Club secretary was Inverness Police Inspector James MacGeoch, a keen photographer and island enthusiast. At the time MacGeoch was Honorary Warden for North Rona and Sulaisgeir National Nature Reserve and had recorded on film the famous Gannet or Guga hunt by the men of Ness. Sadly Jimmy died soon after retiring from the police but Maeve died in 2011 aged 93. Recently, with the MacGeoch family and his friend Dr Finlay Macleod from Ness in Lewis, John was able to see MacGeoch’s classic photographs of the guga hunt published by Acair. North Rona was to feature prominently in John’s island experiences, ringing Leach’s Petrels, one of which was retrapped there no less than 30 years later. From his time in Rum John became good friends with Dr John Lorne Campbell, the eminent Gaelic scholar and folklorist from Argyll; it is less well known that he was a passionate lepidopterist and planted many trees to create wildlife habitat on the Isle of Canna which he bought in 1938.

In 1975 John became involved in the White-tailed Sea Eagle Reintroduction Project on the Isle of Rum – championed by Morton Boyd, encouraged by Roy Dennis and George Waterston, and assisted throughout by a host of others. Shetlander Bobby Tulloch typically provided John with a couple of amusing anecdotes in his talk. As did Professor George Dunnet from Caithness who, as lecturer at Aberdeen University, initiated a long-term study of fulmars in Orkney. John showed a photo of George handling the first fulmar he ringed there in 1951 and then another taken in 1986 as he held the very same bird – it looked exactly the same but George had not weathered quite so well!

George Dunnet with the same fulmar in 1951 and 1986

John could not end his talk without mentioning Murdo MacRury from South Uist who became the first Nature Conservancy warden at Loch Druidibeg. Also two redoubtable naturalists (and columnists in the local Press), Peter and Andrew Currie. There are many others of course it was clear at the end of the evening that not only have the Highlands, and the Hebrides in particular, attracted many fine naturalists over the centuries but they have also generated many of their own. John just felt fortunate to have encountered a few of them in his own lifetime.

Summary – Talk – Nature’s Recyclers: from Dumbledore to Dung Roundheads

Nature’s Recyclers: from Dumbledore to Dung Roundheads

Christine Johnson gave a talk for Curracag on 13th December 2018 in the Dark Island hotel; it was organised by Martyn Jamieson.

Christine started with a diagram to show the importance of ‘Nature’s Recyclers’; in both terrestrial and marine environments there is a huge range of plants, from tiny plankton to huge, old trees. These take in from their surroundings water, air and various minerals, and through the power of sunlight digest them and form further plant material. Over time ephemeral parts of plants and eventually the whole plant will die, if it hasn’t been eaten: various animals from tiny larvae to elephants, consume different types of or parts of plants; then, in due course some of these ‘Primary Consumers’ are themselves eaten by carnivores – the ‘Secondary Consumers’, and they in their turn may be eaten by other carnivores: the ‘Tertiary Consumers’.

All these life forms consuming inevitably produce waste, and indeed in time die themselves, leading to masses of dead plant material, dung, droppings, faeces, and carcasses.

Where does it all go? Why are we not wading through a morass of waste products? – which, in a temperate woodland would amount to 5 tonnes of plant and animal material per hectare.

Although this is waste to the producers, it contains useful elements which can support a huge range of organisms: up to a thousand species per square metre, e.g. bacteria, fungi, and small invertebrates such as nematodes and larger worms, springtails and woodlice.

Christine then concentrated on the fungi, explaining that the part we see above ground is the fruiting body – which may drop spores [the ‘toadstool’ type], or catapult them over a distance [like puffballs]. The part in the growing medium – underground or embedded in leaf litter or wood – is a network of very thin tubes [hyphae] which collect and digest the material for growth; this network can extend over huge distances, in Siberia, for instance, over hundreds of square miles. Only fungi can digest cellulose. There are very small ones which grow on leaves and conifer needles; once they have started the process of breaking down leaf litter other large types move in, and may appear to be growing from the soil rather than reduced plant material. Fruiting bodies on the edges of some of these networks produce ‘fairy rings’. Some fungi grow on dead wood, the hyphae extending into the wood and softening it; when timber falls, other fungi may move in. Some opportunistic fungi will grow on processed timber such as pallets and chipboard.

Not all fungi are processing dead material; some cause problems in live plants, such as root rot in conifers; the oyster mushroom grows on standing trees and derives its nutrition from trapping and digesting nematodes.

While animal scavengers generally deal with the soft parts of other animals, fungi will grow on hard remains such as hair, feathers and bones, eventually digesting them.

Dung consists of partly digested plant material, mainly cellulose, and there are fungi that grow on dung and break it down. As these deposits are often scattered, to ensure that some spores may reach a hospitable site, they are scattered over the grazing area and ingested by the animals, then emerge already within a good growing medium. In the UK alone, there are about 400 species of fungi living on dung.

Christine’s talk was well illustrated with pictures of some of the amazing range of fungi, from large and robust ones to tiny delicate ones, some of them microscopic. It was a fascinating introduction to a small number of an extraordinary range of species and their very important function in the environment.

Summary – Talk – The Amazing Three-spined Sticklebacks of North Uist

On Thursday 8th Novemeber 2018 a small group assembled in the Dark Island Hotel to hear Carl Smith speaking on ‘North Uist – the Scottish Galapagos: a hotspot of stickleback biodiversity’, a talk organised by Martyn Jamieson for Curracag, but open to anyone interested.

Those of us with any familiarity with North Uist are well aware of the numerous lochs scattered across the island in the range of local habitats: moorland and peat bog, machair and the blacklands, and the lagoons in which the salinity can vary from almost marine to practically freshwater, depending on rainfall, tides and spray. Few of us will have realised that these support an extraordinary range of forms of the three-spined stickleback – and that the Queen Charlotte Islands off the west coast of Canada are the only other area in the world known to have a similar diversity of sticklebacks, though there is no suggestion that there is any connection between the two populations – they have developed their differences independently.

Carl Smith, a reader at the University of St Andrews, has been studying sticklebacks for twenty–five years, including ten years in North Uist.

Our sticklebacks will have arrived in the islands only after the last glaciation which covered the islands so 15,000 years ago or less. Probably marine sticklebacks were stranded in freshwater systems or entered them as sea levels changed after the glaciers melted.

Marine three-spined sticklebacks are nearly 3” [7cm] long, have three spines on their backs, bony plates on the sides of the body and fins in the pelvic area with spines that can be locked in place, so small but well protected. In the lochs of North Uist the same fish takes various forms, from something very close to a marine type to a much smaller creature about half the size of the marine form, with no spines, no bony plates and no pelvic fins or spines. There are intermediate forms with varying sizes of spines, areas of plates and pelvic fins or not. One gene controls the differences in the plate formation.

The semi-saline lochs have fish close to the marine type; the machair loch fish range between those with medium protection and those with little, and the peatland lochs contain a range of fish with some plates to those that are completely defenceless and small. Low levels of calcium in these lochs may partially explain the lack of bony features, though other kinds of fish manage to extract enough calcium from their environment to grow normally.

Trout, together with birds and eels, are great predators of three-spined sticklebacks; trying to assess predator levels in lochs led to Carl Smith and his teams fishing a range of lochs with special flies made to look like three-spined sticklebacks, and the conclusion that predator numbers did not explain the presence of small defenceless fish. At present he is working on another explanation as to why there should be so many different forms of these fish.

How does North Uist compare with the Galapagos? One species of finch arrived there about 5 million years ago and over time their descendants have adapted to the different habitats and food sources on the islands in the archipelago, and developed into different forms now recognised as fourteen distinct species. It looks as though the North Uist sticklebacks might be undergoing the same process, but much more rapidly. Whether the tiny defenceless form found in some lochs can really be regarded as the same species as the stoutly armour-plated and spined fish in the sea and lagoons is debateable – but there are all the forms in between.

Dr Smith kindly answered numerous questions and there was some interesting discussion following his fascinating talk. One point of some concern is that other researchers are interested in the North Uist sticklebacks and specimens are in demand. The numbers of the different types in the different lochs are unknown, so whether they might be endangered by over collecting is also unknown. In some lochs there may also be a detrimental effect from, for instance, run-off from application of agricultural fertilisers on the adjacent ground or close to feeder streams, or the presence of fish farms with associated nutrients and build up of fish faeces.

So far the lochs of Benbecula and South Uist seem not to have attracted the same attention; perhaps they also support a diversity of three-spined sticklebacks.

Dr Smith has contributed a paper to the latest volume of the ‘Hebridean Naturalist’, available through the Curracag website, so anyone seeking an authoritative account should look there!