23155_Peltigera:ascophyllum leaflet 17/11/08 10:38 Page 3 BACK FROM THE BRINK MANAGEMENT SERIES BACK FROM THE BRINK MANAGEMENT SERIES The ecology and management of Ear-lobed Dog-lichen (Peltigera lepidophora) and other lichens of rocky river edges ) by John Douglass Design: rjpdesign.co.uk Print: crownlitho.co.uk Peltigera lepidophora ) and Ideal habitat for Ear-lobed Dog-lichen ( Peltigera lepidophora 3 Front cover image: Ear-lobed Dog-lichen ( 23155_Peltigera:ascophyllum leaflet 17/11/08 10:38 Page 2 BACK FROM THE BRINK MANAGEMENT SERIES Peltigera lephidophora © Stephen Sharnoff This leaflet reveals more about the elusive Ear-lobed Dog-lichen (Peltigera lepidophora) and other species of lichens that grow along rocky rivers. What to do if you find them, and how you can help them to thrive. Plantlife is the UK’s leading charity working to Plantlife Scotland protect wild plants and their habitats. The charity Balallan House has 10,000 members and owns 23 nature reserves. Allan Park In 2008, Plantlife is ‘Lead Partner’ for 77 species Stirling under the UK Government’s Biodiversity Action FK8 2QG Plan. Conservation of these species is delivered Tel. 01786 478509 through the charity’s Back from the Brink species recovery programme, which is jointly funded by www.plantlife.org.uk Countryside Council for Wales, Natural England, [email protected] Scottish Natural Heritage, charitable trusts, companies and individuals. It involves its members as volunteers (Flora Guardians) in delivering many aspects of this work. Plantlife’s head office is in Salisbury, Wiltshire, and the charity has national offices in Wales and Scotland. 23155_Peltigera:ascophyllum leaflet 17/11/08 10:38 Page 1 BACK FROM THE BRINK MANAGEMENT SERIES What are lichens? important. Some of the richest sites contain Lichens are curious dual organisms. They are basic rocks (such as mildly calcareous often thought of as plants but in fact they are sedimentary rocks like sandstones and a tight association between an alga or mudstones) or igneous rocks (such as basalts cyanobacteria (photobiont) and a fungus and andesites). Lichens of limestone rivers (mycobiont). Lichens gain their nutrients from are very different from those found on highly the photobiont, which captures the sun's silicaceous river rocks such as quartzite and energy through photosynthesis. The fungus granite. protects the photobiont from drying and from the harmful effects of the sun’s rays. This The Ear-lobed Dog-lichen (Peltigera means that lichens can inhabit some of the lepidophora) is extremely rare in most inhospitable places on earth. Scotland. The Ear-lobed Dog-lichen is one of Britain’s The main body of a lichen is known as the rarest lichens. First recorded for Britain in thallus. Lichens reproduce using fruiting 1971, to date it has still been recorded only bodies, known as apothecia, or by means of on a single rocky outcrop in a river gorge in fragmentation of the lichen itself in special Perthshire. peg-like structures (isidia) or powdery structures (soralia). Dog-lichens (Peltigera lichens) ● Peltigera species are leafy (foliose) lichens Lichens of rocky river edges and have a distinctly different upper and Scotland, with its wet climate, great variety lower surface. The upper surface is of rock types and glacial history has some of sometimes smooth and shiny or matt and Europe’s best developed river communities minutely hairy. The lower surface always of plants, fungi and lichens. River rocks has root-like structures, known as rhizines, provide important habitats for lichens. and often has pale or dark veining. There are over 80 restricted to this habitat ● They are among the largest and fastest alone including seven British Red Data Book growing of all the lichens and may grow up species. Lichen communities are best to 2 to 3 centimetres per year. developed in the upper to middle stretches ● Dog-lichens are also known as Dog-tooth of rivers, whereas eutrophication and heavy lichens as their root-like rhizines resemble silting reduces lichen diversity in the lower canine fangs. These rhizines are found in alluvial stretches. Fast water flow in the other lichens but they are rarely as higher reaches can cause heavy scouring of pronounced as in the Dog-tooth lichens. In rocks, making them unstable habitats. Lichens medieval times Peltigeras were thought to occur in bands depending on how well they be a good remedy for dog bites. are adapted to submergence. The richest ● They sometimes produce red-brown or sites are rocky stretches that are not too black fruiting bodies. These are spore- deeply shaded by bank-side vegetation, and bearing apothecia, which are saddle where there are large areas of exposed rock shaped, flattened or oval. The apothecia are outcrops and boulders. Rock type is produced on the ends of the lobes. 1 23155_Peltigera:ascophyllum leaflet 17/11/08 10:38 Page 2 BACK FROM THE BRINK MANAGEMENT SERIES ● Peltigeras are often relatively rapid 0.5 millimetres in diameter and occur on the colonisers. upper surface of the lobes. The under- ● Nineteen species of Dog-lichen occur in surface is whitish with distinct, pale, grey-fawn Britain, all of which are found in Scotland. veins and small un-branched rhizines. This is an ephemeral species and its abundance and More about the Ear-lobed Dog- apparent health may be seasonal. It is lichen (Peltigera lepidophora) thought that the species is best developed Peltigera lepidophora is bluish grey when wet, during the autumn, winter and spring months brownish grey when dry and can grow up to and is less apparent in summer. six centimetres in diameter with lobes to one centimetre wide. The lobes are concave or Conservation protection status of ear-shaped with inrolled margins, which are Peltigera lepidophora frequently torn or eroded. Small scale-like ● Legal status: Schedule 8 of the Wildlife and outgrowths, called isidia, are approximately Countryside Act 1981. ᮢ Peltigera lepidophora habitat showing its position among grasses near the top of the outcrop © John Douglass 2 23155_Peltigera:ascophyllum leaflet 17/11/08 10:38 Page 3 ● Red Data Book Category: Critically Endangered, Nationally rare. ● UK BAP (Biodiversity Action Plan) priority species. Habitat and distribution of Peltigera lepidophora in Britain The only known British site where this lichen is found is a calcareous sandstone conglomerate outcrop along a steep, wooded gorge in Perthshire. Winter and spring water levels are very high and the site is liable to inundation from the river, whilst in summer months the outcrop is subjected to long dry spells. The outcrop contains deposited silt, providing some nutrient enrichment. Colonies of bryophytes and annuals occur here with occasional crustose and Dog-lichens. It is relatively well-lit, due to its position on the north side of the river, but is sheltered by steep wooded slopes on either side. The lowest occurring colonies of this lichen occur in a zone where the more submerged-tolerant species of bryophytes occur. World distribution and habitat of Peltigera lepidophora Peltigera lepidophora is frequent in Scandinavia, local in central and eastern Europe, and rare in western Europe. It has also been recorded in Peltigera lepidophora showing the plate-like Hawaii, North America, South America and isidia on top of the lobes © John Douglass New Zealand. Its European habitat is on the ground on slightly calcareous substrata, sometimes over bryophytes, and often with some nutrient enrichment. It occurs across some of the northern and central states of North America on exposed soil, road cuts and trail banks usually in open, dry habitats. In New Zealand it has been found at 1800 metres on calcareous soil. 3 23155_Peltigera:ascophyllum leaflet 17/11/08 10:39 Page 4 BACK FROM THE BRINK MANAGEMENT SERIES Peltigera didactyla showing the circular soralia (powdery reproductive structures) © John Douglass Other dog-lichen species which Peltigera membranacea is very common and may be confused with the Ear-lobed forms wide radiating patches up to 40cm Dog-lichen across. The lobes are up to 3cm wide, are grey when dry and brown when wet, and have Peltigera didactyla has powdery granules in a felt-like, ridged upper surface. The lower distinct circular patches, called soredia, that surface is whitish with pale, raised veins and form on the lobe surface. dispersed bottle-brush like rhizines. Peltigera praetextata is generally larger, with Peltigera britannica is occasional to rare, and lobes up to 3cm in size and has small lobe-like coloured bright green when wet and pale isidia mostly clustered along the lobe margins brownish-grey when dry. The lower surface or along the edges of splits on the upper has indistinct veins and the upper surface has surface of the lobes. small, dark, button-like cephalodia. These are structures containing a cyanobacterial photobiont, which is a different photobiont to that of the thallus, or main body of the lichen. Peltigera hymenina is very common, forming large patches up to 20cm across with matt or shiny grey or brown lobes up to 2cm wide. The lower surface is cream or light brown with flat veins and pale simple rhizines. ᮤ Peltigera praetextata showing the plate like isidia, which mainly develop along the edges of the lobes © John Douglass 4 23155_Peltigera:ascophyllum leaflet 17/11/08 10:39 Page 5 BACK FROM THE BRINK MANAGEMENT SERIES Peltigera mambranacea showing the fang-like rhizines (root-like structures) © John Douglass Peltigera horizontalis has a blue-grey upper surface, often tinged brown and with glossy lobes. The lower surface is pale at the edges but darker towards the centre. The apothecia (orange/brown spore producing bodies) are horizontal to the lobes. ᮣ Peltigera hymenina showing the apothecia (orange-brown spore producing structures) © Paul Whelan ᮢ Peltigera horizontalis showing the apothecia ᮢ Peltigera britannica showing the dark, flat (orange-brown spore producing structures) which cephalodia on the green lobes.