Tenerife: Visit to Las Canadas National Park

One of the most dramatic and rewarding experiences in Tenerife is a visit to Las Canadas National Park. This wonderful area is designated as a World Heritage Site. The whole park is a caldera that consists of the remains of a super volcano that collapsed nearly two hundred thousand years ago. Today, we think of the massive volcanic cone of Teide as being impressive; it is the highest mountain in Spain, but it is nothing compared to the original volcano that stood on this site.

A visit to Las Canadas National Park from Puerto de la Cruz starts with a drive through a large amount of suburbia. However, this can be interesting for the botanist. On a wall beside a suburban road, we found the Canarian endemic member of the stonecrop family, Aichryson parlatorei in excellent flower. Entering the edges of Aguamanza, and before reaching the pine forest, on the roadside verge were fine examples of the beautiful, purple flowered endemic Pericallis echinata and on the same verge was the endemic figwort, Scrophularia smithii.

Aichryson parlatorei

Pericallis echinata

On leaving the suburbs, the terrain begins to rise up towards the caldera through a zone of Canarian Pine Forest. The species of pine making up the woodland is Pinus canariensis and is endemic to the Canary Islands. Especially on Tenerife, it produces large areas of forest. Amongst other things, this habitat is home to the delightful and endemic Blue Chaffinch. As lichens are a group that I am particularly interested in, I was delighted to see a range of species that would never grow on pine in Britain, but are doing exceptionally well on the trees here. Species included the hairlike Alectoria sarmentosa and Usnea articulata which were surprisingly difficult to separate when growing together in Tenerife. Perhaps the greatest surprises were great cabbage-like bushes of Common Lungwort Lobaria pulmonaria and the delightful, bright yellow lichen Teloschistes flavicans. This latter is particularly rare in Britain, and is particularly pollution sensitive.

Canary Island Pine Forest
(Photograph: Amanda Davey)

Lobaria pulmonaria

Teloschistes flavicans – photographed on the Anaga Ridge

At lower levels, the flowering plant flora of the woodland is not rich, but as it opens out higher up, the verges especially support a wide range of species. These include the almost white endemic Sideritis oroteneriffae which seems to be restricted to a particular altitude zone in the higher part of the forest. Sideritis is another of those genera that has many endemic relatives in the Canary islands. Also seen here are Aeonium sedifolium and areas where the beautiful, if introduced, Californian Poppy makes a striking show. Another rather scarce little plant from this zone is Helianthemum juliae. The distinctive black triangular shapes at the base of the petals help to distinguish it from other rock roses. It grows amongst its much taller relative Cistus symphytifolius with its large pink flowers. In this same area, the close relative of Cistus symphytifolius occurs, but is rare and differs only slightly. This is Cistus osbeckifolius, a species that I looked out for hard, but failed to find.

Sideritis oroteneriffae

Aeonium spathulatum

Helianthemum juliae

Cistus symphytifolius

Once out into the open and arid countryside of Las Canadas Country Park, the main features are the dotted, bushy clumps of species such as the white Spartocytisus supranubius, the yellow Tolpis webbii and Adenocarpus viscosus. The white flowered Argyranthemum teneriffae is abundant, especially by the road, as is the scabious relative Pterocephalus lasiospermus. These are the main components of much of the flora of Las Canadas.

Teide

Road through Las Canadas
(Photograph: Amanda Davey)

Las Canadas Vegetation
(Photograph: Amanda Davey)

Argyranthemum  teneriffae

Pterocephalus lasiospermus

Spartocytisus supranubius

It is on approaching the base of Teide and the Parador that the most dramatic species of the area becomes such a feature. This is the endemic bugloss Echium wildpretii that is virtually restricted to Las Canadas in the world. Outside Las Canadas, and entering it from the south, it can be encountered just above Viraflor where Lotus bertelotii can be seen so well. Close to the base of Teide is the real home of Echium wildpretii, where its tall spikes can dominate the arid volcanic landscape.

Echium wildpretii
(Photograph: Amanda Davey)

One species I had particularly hoped to find is the endemic Viola cheiranthifolia. This delightful little plant grows amongst stones on the slopes of Mount Teide itself. Although I was given directions to a relatively low altitude spot where it was supposed to be, even scanning with binoculars I failed to find it. I had also hoped perhaps to see it in one of the gardens I visited, but this plant eluded me. Perhaps May is the wrong time of year for it.

In the past, there were gardens surrounding the Park Visitor Centre, where a number of the endemic species of Las Canadas could be seen. This included the rare Cheirolophus teydis with its pale yellow flowers. Cheirolophus is another important genus with several Canarian endemic species, and most are rather rare, and restricted in range. I have only ever seen this one in flower in September and October. This time I could not even see it in seed.

Cheirolophus teydis

Another blue flowered endemic with a very restricted range is Nepeta teydea. My experience is that it is restricted to a small area to the south west of Teide itself where it is easy to see on the roadside verge. Also growing in this area is the ordinary, but endemic Arrhenatherum calderae, a relative of our very common false oat grass. This one, however is extremely restricted in occurrence.

Nepeta teydea

Arrhenatherum calderae

No visit to Las Canadas would be complete without a chance to marvel at its volcanic splendour. At 3718 metres (12198 feet) Mount Teide is a high, and impressive mountain. At this altitude, it frequently retains snow on its upper reaches well into May. It is possible to ascend the mountain by cable car. More often than not, the view, although majestic, is a sea of white cloud far below, out of which emerge other members of the Canarian archipelago. Beneath the summit can be seen Teide’s Nostrils. These are the result of an eruption that was witnessed by Columbus as he sailed past Tenerife in the 16th century. The last eruption took place in 1909, and during one eighteenth-century eruption, the harbour of a fishing village (Garachico) on the north coast was dramatically filled with larva.

Teide’s Nostrils

Landscape dominated by volcanic lava
(Photograph: Amanda Davey)

Solidified lava flow near the base of Mount Teide

Banded volcanic ash near the edge of Las Canadas National Park

La Palma rising above surrounding cloud

Two features of particular importance are the dramatic lava flow that can be seen from the road close to the base of Mount Teide. A convenient car park allows the visitor to enjoy fine views of it. On leaving Las Canadas on one of the major access roads that heads to La Laguna, the road passes by a spectacular series of layers of ash ranging from white to almost black. Once again, there is a convenient car park here, and in suitable weather, which is frequent, the island of La Palma to the west can be seen rising from the surrounding cloud bank. One feature of Canarian weather seems to be that the Anaga Ridge, and Puerto de la Cruz are frequently smothered in cloud while Las Canadas National Park rises majestically above it.

More on the Exciting New Lichens in Sussex

Teloschistes chrysophthalmus - the Tangerine

Mark Jackson who lives in Southampton should be crowned the Teloschistes chrysophthalmus King. Recently, I received an e-mail from him saying that he had found eight bushes with Teloschistes to the north east of Brighton, and another two not too far from where he originally found it. Inspired by this news, I went over to have a look at areas between Birling Gap and Beachy Head where there were masses of thorn bushes in open country that seemed ideal. I was utterly convinced I would be successful, but in the event, I failed to find any. Having never ever actually seen Teloschistes chrysophthalmus without being shown it, I resolved to go and have a look at one of Mark’s sites for which I had very accurate grid references. In spite of this, it took me some time to find his two bushes with it on.

Exciting New Lichens in Sussex – our Sequal

The Teloschistes chrysophthalmus habitat in Sussex weald

The morning was one of the brightest spring days of the year so far. Since January 3rd, my wife Amanda has been taking a photograph of exactly the same view of a field near where we live. Since being shown Teloschistes chrysophthalmus just north of Brighton, we have been keeping our eyes open for it. This morning, having taken her photograph, Amanda was struck by the assemblage of lichens, including the golden Xanthoria species that seem to be associated with Teloschistes chrysophthalmus  growing on a blackthorn bush nearby. She went over to give the bush a casual look.

After perhaps half a minute, the air went blue.

“Sod it!” She cried.

“What’s the matter.” I replied, furrowing my brow in concern.

“Come and see!” she said.

“I’m not sure I want to see something that’s not too pleasant,” I added.

The twig with Teloschistes chrysophthalmus

“You’ll like this,” she replied enthusiastically. I walked over to where she was standing, and she pointed to a very small, very fertile orange coloured lichen. Indeed, the fruits seemed to be raised on definite branches, and I could see what I thought were eye-lash like cilia surrounding the fruit. It looked very promising. Amanda dashed inside to get my hand lens and camera. Moments later, I was able to confirm our suspicions with my hand lens.

The new Teloschistes chrysophthalmus

The lichen was very small, but I was in no doubt whatsoever that this was indeed the beautiful Golden-eyed Lichen Teloschistes chrysophthalmus and the second record of it for East Sussex and one of the mounting number of sightings in southern England since October last year.

Exciting New Lichens in Sussex

Sussex Teloschistes chrysophthalmus

On Boxing Day 2012, I enjoyed some most exciting natural history. On 23rd of December, I received an e-mail informing me that the lichen Teloschistes chrysophthalmus had been found on two hawthorn bushes to the north of Brighton. The finder, Mark Jackson had recently just got interested in lichens, and asked me about the status of Teloschistes chrysophthalmus in East Sussex. The answer is simple, it is the first recent record for Sussex, there being three early 19th Century records from Shoreham, near Brighton and also near Lewes. On 23rd of December my knowledge of the current history of Teloschistes chrysophthalmus was as follows:

·    In 1994, it had been discovered at Slapton Ley, but the bush on which it grew was cleared as part of conservation scrub clearance.
·    Next, it was found on a hawthorn bush on the shores of the Drift Reservoir in Cornwall, but when the water level rose and submerged the bush, its only known modern site was once again lost.
·    More recently it was found on a branch fallen from an apple tree in Herefordshire.

Not a very promising situation for its continued survival, but shortly after that, it was found in County Cork and as far as I know, that site is still extant. It also occurs on Guernsey on two bushes where I saw it recently. In Jersey however, it was last seen in an orchard back in 1966. A recent trip to the site confirmed that all the apple trees had gone.

On Boxing Day I met up with Mark Jackson and he showed me the two bushes each with just one Teloschistes chrysophthalmus. We had a good look round at other trees, but found no more. However, on our way back to the car, Mark found a minute, pink lichenicolous fungus growing on a twig. I photographed it, and sent off the photograph to the experts. It is Illosporiopsis christiansenii and new to Sussex. Mark is lucky in having an excellent eye for lichens, as well as a great enthusiasm for them.

Woodland Continuity

Common Lungwort - Lobaria pulmonaria

It was Francis Rose who, way back in 1974, first recognised the value of lichens in assessing ecological continuity in woodland. A list of seventy species was compiled by the British Lichen Society which were found to be most closely associated with ecological continuity and lack of disturbance. This list was used to arrive at the New Index of Ecological Continuity (NIEC). Added to this, a list of rarer, bonus species could be used to calculate a second index. These indices work well for much of Britain, however further indices were formulated for areas where other lichens were found to indicate continuity. Where the large and showy common lungwort Lobaria pulmonaria works well as an indicator throughout much of England, it is a common species in Western Scotland, and its presence there cannot be used as an indicator of continuity. For upland England and Wales, as well as in Western Scotland, the Eu-Oceanic Calcifuge Woodland Index is used. Further indices are used in Scotland and Western Ireland.

Heterodermia japonica growing amongst a form of
Hypnum cupressiforme

It was noticed while undertaking a survey in Eastern Cornwall in a nature reserve known to consist of ancient woodland, that the nationally scarce lichen Heterodermia japonica occurring on a beech branch was fertile, and supported a number of small, disc like fruits or apothecia. A day or two later, there was a depression in the lichen where the fruits had been. It seemed most probable that a slug had browsed them off. Some six months later, the site was revisited, and small daughter colonies of the lichen were found up to six feet away from the parent lichen. If, as seems probably the main vector for spreading the spores of ancient woodland indicator lichens is the digestive system of slugs, then distribution is going to be very slow indeed. No slug will ever take the trouble to cross a major road simply to spread a particular species of lichen.  Slugs are also ideal as vectors as the spores are conveniently attached to the substrate in their slime trail. It would be interesting to experiment by collecting slugs from known ancient woodland sites and introduce them to more recent sites to see if indicators of continuity became established.

Francis Rose, and Richard Hornby of the then Nature Conservancy Council, made a list of higher plants reckoned to be associated with ancient woodland. While the clear felling of a wood totally removes the corticolous lichen flora, higher plants are more robust, and are therefore useful in assessing ancient woodland sites. It is most important to remember that the higher plant list consists of common species, and that it is the total of species present that is significant. The absence of rarer species lacks significance just as does the presence of one or two of the common indicators. Higher plant indicators are all photosynthetic, and therefore need adequate light levels. In many ancient woodlands, due to the current lack of grazing, the ancient woodland flora is confined to rides, or to the roadside banks of the edge of woods.


The British Bryological Society have also made a list of mosses and liverworts most closely associated with woodland continuity that works well and I understand that in the insect world, similar lists of beetles and hoverflies have been made. It would be most interesting to know if there are correlations between all ancient woodland indicator lists.

Barnacle Lichen - Thelotrema lepadinum

One of the difficulties of using lichens, and to a lesser extent bryophytes as indicators of ecological continuity is their sensitivity to air pollution. Throughout most of Central and South-eastern England until some thirty years ago, acid rain and industrial pollution all but destroyed the lichen flora totally, and with it the information it could give. It is lucky that the Barnacle Lichen, Thelotrema lepadinum, which is a most useful indicator, is relatively tolerant of sulphur dioxide in the atmosphere, and it has been found, as would be expected due to the ecological continuity of the sites, in both Epping Forest and Hatfield Park. Even low lichen indices of continuity in these areas can be treated as significant.

Most of the early work that related lichen richness with ecological continuity took place in the deciduous woodlands of England, Wales and North-western Scotland. In Central and Eastern Scotland there are pine forests of great ecological importance and continuity. The lichen flora associated with these trees is very different, as are the habitats they provide. Dr Brian Coppins, the foremost Scottish lichenologist, is known to say that the only good pine tree [for lichens] is a dead pine tree. He points out that a pine provides habitat for lichens for a longer period as a standing dead tree than it does when alive. While coppice woodlands with hazel or hornbeam in England can be important for lichens, and the coppice poles can support a rich flora, this is nothing compared with the incredible richness found in a few very important and ancient hazel woodlands in western Scotland and in the Hebrides.

A further index using lichens is also used, but these days only occasionally. This is the Revised Index of Ecological Continuity (RIEC). In this case thirty species are used, and by multiplying the number of species by 5, a figure for the index is found as a percentage. A score of 100% is reckoned to equate to a wood with perfect ecological continuity. However scores higher than a hundred are possible such as Glen Shira in Scotland with a score of 130%. Using the New Index of Ecological Continuity, a total of thirty or more species that includes bonus species is thought to indicate a wood of high conservation value. Parham Park which is arguably the best example of ancient woodland in Sussex has a total of 27 NIEC species added to which should be 3 bonus species bringing a total score of 30. In other parts of Britain, much higher totals are found.

Francis Rose was never keen to indicate the meaning that should be given to higher plant indicator totals. However, he told me he was of the opinion that a score below twenty species indicated a wood of low conservation interest. Similarly a score of twenty bryophytes indicate conservation value, though this is reduced to fifteen throughout South-eastern England.

Hoverfly - Calliprobola speciosa

Beetle - Helops caeruleus

Some groups of insects also contain species that are good as indicators of ecological continuity. Two groups certainly spring to mind which are  hoverflies and beetles. Two illustrated here are the rare New Forest hoverfly Calliprobola speciosa which could be used, as could the beetle Helops caeruleus. There are many more hoverflies and beetles that could be used as indicators of ecological continuity.

This account has been to do with ancient woodland with continuous canopy cover. This type of woodland is not rich in butterflies. For butterfly richness, it is the woodland rides and their floristic richness that are important.  Woods such as Bernwood in Oxfordshire are soft wood plantations, but the richness of the rides make them outstanding for insects such as butterflies. Beautiful bluebell woods are not examples of woodland with long continuity, but are none the less very important. Similarly, it is coppiced woodland that generally provides habitat for greatest flowering plant biodiversity. It is a balance that is required as well as the importance that is given to woodland with a long history.

Collections and Ecology

One of my earliest memories, from when I was about 6 or 7 years old, is of finding a strange insect, which fascinated me. At the time, we lived in the depths of Norfolk, and wildlife was my main pastime. My father suggested we should take my find to the Castle Museum in Norwich. I was shown into an office where that great naturalist Ted Ellis was in charge of natural history. He looked at my offering, and identified it as the nymph of a species of shield bug.

Death’s Head Hawkmoth, a preserved specimen

Death’s Head Hawkmoth, the caterpillar

He then showed me a cabinet drawer in which rank upon rank of similar insects were displayed with military precision. It just happened that he had some death’s head hawkmoth caterpillars feeding on a potato plant close by. Already I was aware of hawkmoths, and of the rarity and iconic status of the death’s head hawkmoth.  In all, I probably spent twenty minutes in that room, but the experience had been one of the most influential twenty minutes of my life. A few years later, the family was staying in London, and my father said he was going to give me a very special surprise. He did not tell me what it was till we got there. He took me to the South Kensington Natural History Museum where I was awe struck by the variety and majesty of so much natural history.

Another early memory was of rolling back faded grey cloth coverings to reveal the insect collections beneath at Ipswich Museum.

The Natural History Museum, Dublin

More recently, I saw similar collections in Dublin’s Natural History Museum. The Biological Museum in Dublin has become a museum in itself showing the history of natural history in museums. As such I believe it is fantastically important. Museums where youngsters could go and explore quantities of specimens, and learn so much from them is largely a thing of the past. Today, museums all too often are teaching displays fulfilling a role, which is probably just as well covered by the internet. Museum collections are no longer valued as they used to be, and no photograph or diagram will ever give the information that a preserved specimen can give. For many years, I worked as a biological curator in a regional museum, and was taught that the specimen was the most important aspect of the work of a museum. My first professional experience was in the 1970s at Leicester Museum. At Leicester, the collections were beautifully conserved, catalogued and displayed. The public, and especially keen youngsters were encouraged to come and use the collections in order to learn their way around the complex relationships within difficult insect groups. The collections were used like a reference library.

Four full time taxidermists worked to increase the collection of birds and mammals. Throughout Leicestershire, members of the public kept their eyes open for road casualties, and it was with these that the collections were enlarged. Oh yes, the days of what’s hit is history and what’s missed is mystery were very much a thing of the past. However, the collections continued to increase in size and importance. While I was there, an aquatic warbler killed by accident, possibly by a cat, was added to the collections. No one can be an effective ecological consultant without a working knowledge of the fauna and flora in the sites to be studied, and the specimens housed in museums are a goldmine for anyone learning their way around the complexities of Britain’s wildlife.

Looking at Wildlife Species Worldwide. Tying it in.

It was 1990. The darkness was just beginning to brighten outside. My window was open, and a pleasant, cool breeze redolent with tropical perfumes tantalised my nostrils. It must have been about half past five in the morning, though my body probably registered as much later as I had passed through several time zones in the previous twenty four hours. This was the start of my first day ever in Costa Rica and I was in a hotel room in the capital, San José. A bird began to twitter starting the dawn chorus.

“That has to be a species I have never seen before,” I told myself and in a flash, I was out of bed, and dressed. Soon I was out in the streets that surrounded the hotel. They contained suburban houses with fine gardens ablaze with Bougainvillea and other tropical flowers.

Eyelash Viper - Costa Rica

I tracked down approaching the source of the song of that first bird of the day. It was a Rufous-collared Sparrow, a species that would fill the niche of the house sparrow, if house sparrows were not probably the most cosmopolitan of all birds. I had just made the acquaintance of the Rufous-collared Sparrow or Rufie as they are called by birders in tropical America, when a dark flash passed me like an arrow. Soon, it was stationary, hovering close to the flowers of a Bougainvillea, its wings a greenish blur. This was my first hummingbird. It had an orange brown tail and went onto my lists as a Rufous-tailed Hummingbird. Soon, I was enjoying a tiny owl. This was a Ferruginous Pigmy Owl sitting on a telegraph wire.  Two American warblers joined in, and these were Tennessee and Yellow Warblers. I saw fifteen new birds before breakfast and one of the most amazing was a Blue-crowned Motmot that swung its amazing tail feathers backwards and forwards like the pendulum of a clock.

Inspiration through Ecology

Simon Davey studying lichens in Jersey

Life on Earth is a near infinite mix of species with complex inter relationships. It is quite incredible how every group of animals and plants has evolved in a way that also gives the naturalist a perfect avenue of study and development of knowledge. Take birds, for instance. An embryo birder would have little difficulty in distinguishing a robin, a blue tit and a blackbird in the garden. As his experience develops, challenges such as leaf warblers and waders present themselves to give a puzzle equal to any Times crossword.

Lichenologists in a Dutch churchyard

Personally, one of my greatest interests is in lichens. I suppose many would be put off lichens believing them to be far too complicated to get into. However, the ecological value of lichens makes them a challenge that is so worthwhile. Anyone with experience of suburban areas, and with even the slightest observation of the natural world, cannot fail to have noticed the scrambled egg like crusts growing on asbestos garage roofs, walls, or the enriched dog-pee zone at the base of trees in urban parks.

Xanthoria parietina

This is the lichen Xanthoria parietina. With something like 1800 species in Britain, lichens present a challenge that could keep any naturalist inspired and occupied for a lifetime. As with birds, some are easily identified, while the identification procedures to name others require a series of complex processes involving chemicals, high power microscopes and the accurate measurement of structures such as spores.  Lichens are probably the fussiest group about the environment in which they can survive. The presence or absence of many allows an ecologist to make a rapid initial evaluation of the health and ecological importance of a site. It is well known that lichens cannot tolerate acid rain. It was probably lichens that caused environmentalists to take seriously the problems, to us all, of industrial air pollution more than anything else. A few groups of species, and especially lichens, beetles and hoverflies indicate by their presence or absence the ecological continuity and lack of negative disturbance in the places in which they live.