Tortula cernua (Huebener) Lindb. Flamingo moss POTTIACEAE SYNONYMY: Desmatodon cernuus (Huebener) Bruch & Schimp.

Status: Bryophyte Red Data Book – Endangered (2001) English Nature Species Recovery Programme

Current GB status (www.jncc.gov.uk) - UK BAP Priority Species Endangered (2008) Status in Europe: Rare Lead Partner: Plantlife International

UK Biodiversity Action Plan: These are the current BAP targets following the 2001 Targets Review: T1 - Maintain the range of this species in Britain and enhance its total population size T2 - Regenerate colonies of this species from a possible spore-bank at least three suitable sites by 2010. T3 - Establish by 2005 ex situ stocks of this species to safeguard extant populations. T4 - If regeneration from spore banks fails, assess by 2010 the feasibility and desirability of undertaking translocations to suitable habitat at three sites. Progress on targets as reported in the UKBAP 2002 and 2005 reporting rounds can be viewed on the BARS (Biodiversity Action Reporting System) website: http://www.ukbap- reporting.org.uk/status/species_habitat_nat_status.asp?C=1&X=%7BA704A9B1%2D6A09%2D49DA %2DBF0A%2DA8A126228AA7%7D The full Action Plan for Tortula cernua (UK Biodiversity Group 1999) can be viewed on the following web page: http://www.ukbap.org.uk/UKPlans.aspx?ID=260 UKBAP species actions are currently under review following the recent revision of UKBAP species (2007). The current UK list of Priority Species can be viewed on the following web page: http://www.ukbap.org.uk/PrioritySpecies.aspx?group=6 Contents

1 Morphology, Identification, Taxonomy & Genetics 1.1 Morphology & identification 1.2 Taxonomic & genetic considerations 2 Distribution & Current Status 2.1 World 2.2 Europe 2.3 2.3.1 2.3.2 Northern Ireland 2.3.3 Scotland 2.3.4 Wales 3 Ecology & Habitat Requirements 3.1 Communities & vegetation 3.2 Dispersal & strategy 3.3 Habitat requirements in the UK - conclusion 4 Threats 5 Management Implications 6 Ex situ Conservation 7 Recommendations for Future Work 8 References 9 Acknowledgements 10 Contacts 11 Links 1 Morphology, Identification, Taxonomy & Genetics

1.1 MORPHOLOGY & IDENTIFICATION

Description Tortula cernua is a small green acrocarp with a drooping or horizontal capsule on a long wavy seta, looking slightly like a flamingo's neck and head. The gametophyte is similar to many other species of Pottiaceae, being short, unbranched and green, with rather broad, mucronate leaves. Microscopically, the leaves are recurved, denticulate above, and bordered with cells that are longer and narrower and more pellucid than most of the lamina cells. The sporophyte consists of a shortly oval capsule on a long, wavy seta. The spores, at 36-40 µm, are large in comparison with most related species. Colonies sometimes cover large areas of disturbed calcareous ground. However, microscopic features are necessary to distinguish it when sterile. No other British species of Tortula has bordered and clearly denticulate leaves. However, these characters are shared with species of the genus Hennediella, but these have broader leaves and erect capsules. In practice T. cernua is readily identified in the field because it is usually produces abundant sporophytes.

According to Blockeel (2000), "…in practice, T. cernua can be recognised reliably and without difficulty in the field if sporophytes are present. The short acrocarpous growth form, mucronate leaves and strongly curved capsule on an erect seta are distinctive. Dicranella varia, which grows in similar habitats to T. cernua and has a curved capsule, is easily distinguished by its linear- lanceolate, secund leaves. Sterile shoots cannot be identified with certainty in the field, as they resemble other species of Pottiaceae."

According to Crum & Anderson (1981), distinctive features of T. cernua include "…horizontal (or drooping) capsules…" and a "…distinctive leaf structure - leaves oblong, abruptly pointed, with margins revolute and yellowish-bordered and upper cells hexagonal to rhomboidal (and at least sometimes adorned by C- shaped papillae)...".

Figure 1 - Tortula cernua (flamingo moss) at Lindrick Common (Photograph by Nick Hodgetts)

Figure 2 - Tortula cernua (flamingo moss) at Lindrick Common (Photograph by Nick Hodgetts)

1.2 TAXONOMIC & GENETIC CONSIDERATIONS

The specific status of Tortula cernua appears to be taxonomically uncontroversial, at least at present.

2 Distribution & Current Status

2.1 WORLD

Tortula cernua is a circumpolar species known from the High Arctic in Svalbard, Ellesmere Island and northern Greenland, south to montane areas of northern, central and eastern Europe, central Asia and New Mexico (Hill et al. 1992). It is apparently frequent in northern Newfoundland.

2.2 EUROPE

Nyholm (1975) describes it as occurring in "scattered localities along the coast from Sör-Tröndelag to Finmark" in Norway, and in North, West, East and Central Europe. Manuscript distribution notes compiled by the European Committee for the Conservation of Bryophytes (pers. comm.) list T. cernua as occurring in Finland, Iceland, Norway, Russia, Svalbard, Sweden, Belgium, Britain, Austria, the former Czechoslovakia, Germany, Switzerland, Hungary, Poland, Yugoslavia and Italy. It is classified by Hill & Preston (1998) and Hill et al. (2007) as Circumpolar Boreal-montane.

2.3 UNITED KINGDOM

Overview In Britain Tortula cernua has a distribution centred on the Magnesian Limestone of South , North Nottinghamshire and north-east Derbyshire. Recorded from about 20 sites to date in the United Kingdom (all in northern England), recent records for T. cernua are restricted to a small number of post-industrial sites in the Worksop and areas. Blockeel (2000) reviewed the status of T. cernua in Britain, and Howes (2000) summarised its status in Yorkshire. Since then, known populations have been monitored regularly (Hodgetts & Blockeel 2002; Hodgetts 2003, 2004, 2005, 2006a, 2006b), and Headley (2004) has made more detailed ecological investigations. T. cernua is listed as Endangered in the British Red Data Book for mosses and liverworts (Church et al. 2001), and in the updated 2005 bryophyte Red List (www.jncc.gov.uk).

Figure 4 - British distribution of Tortula cernua

Open circles: pre-1980. Closed circles: 1980-2005

Record of T. cernua are listed in Table 1.

Table 1 - Records of Tortula cernua – historical and extant

Locality County Vice- Grid ref. Alt. Date Recorder Notes count y Woodend, Nottinghamshi 56 SK58 - 01/09/19 J. Brown - Shireoaks re 46 Steetley Derbyshire 57 SK57 - August Unknown Steetley Wood 1946 Steetley Derbyshire 57 SK546789 60 2000 Tom >60 fertile Blockeel shoots Steetley Derbyshire 57 SK546789 60 20/12/20 Nick >10,000 fertile 01 Hodgetts shoots: hundreds of thousands of sterile shoots Steetley Derbyshire 57 SK546789 60 06/12/20 Nick >10,000 fertile 02 Hodgetts shoots: hundreds of thousands of sterile shoots Steetley Derbyshire 57 SK546789 60 08/09/20 Nick >10,000 fertile 03 Hodgetts, shoots Jenny Duckworth, Alistair Headley Steetley Derbyshire 57 SK546789 60 08/12/20 Nick No fertile shoots 03 Hodgetts but hundreds of thousands of sterile shoots. Steetley Derbyshire 57 SK546789 60 01/12/20 Nick >10,000 fertile 04 Hodgetts shoots: hundreds of thousands of sterile shoots. Steetley Derbyshire 57 SK546789 60 16/11/20 Nick >10,000 fertile 05 Hodgetts shoots: hundreds of thousands of sterile shoots. Steetley Derbyshire 57 SK546789 60 December Nick ca. 15,000 2006 Hodgetts fertile shoots: hundreds of thousands of sterile shoots. Plumley lime Cheshire 58 SJ7075 - 23/10/19BBS - beds 66 recorder Anston Quarry South-west 63 SK520823 - 2001 Tom ca. 130 fertile Yorkshire Blockeel plants. None found in Jan 2004, when the trench the plants occurred in had largely been filled in and covered with a track. The site was more or less destroyed by infilling with soil in Nov. 2004. Brancliffe Lime South-west 63 SK541816 70 2000 Tom >400 fertile Works Yorkshire Blockeel shoots Brancliffe Lime South-west 63 SK541816 70 06/12/20Nick >400 fertile Works Yorkshire 01 Hodgetts shoots; thousands of sterile shoots Brancliffe Lime South-west 63 SK541816 70 06/12/20Nick >400 fertile Works Yorkshire 02 Hodgetts shoots; thousands of sterile shoots Brancliffe Lime South-west 63 SK541816 70 08/12/20Nick ca. 100 fertile Works Yorkshire 03 Hodgetts shoots; thousands of sterile shoots. Brancliffe Lime South-west 63 SK541816 70 01/12/20Nick ca. 4000 fertile Works Yorkshire 04 Hodgetts shoots; thousands of sterile shoots. Brancliffe Lime South-west 63 SK541816 70 16/11/20Nick ca. 1100 fertile Works Yorkshire 05 Hodgetts shoots; thousands of sterile shoots. Brancliffe Lime South-west 63 SK541816 70 1/12/200Nick ca. 900 fertile Works Yorkshire 6 Hodgetts shoots; thousands of sterile shoots. Lindrick Common South-west 63 SK58 - 29/01/19 Unknown - Yorkshire 47 Lindrick Common South-west 63 SK554827 60 2000 Tom >400 fertile Yorkshire Blockeel plants Lindrick Common South-west 63 SK554827 60 21/11/20 Nick ca. 150 fertile Yorkshire 01 Hodgetts plants Lindrick Common South-west 63 SK554827 60 16/12/20 Nick ca. 50 fertile Yorkshire 02 Hodgetts plants Lindrick Common South-west 63 SK554827 60 08/09/20 Nick Several dozen Yorkshire 03 Hodgetts, fertile plants. Jenny Duckworth, Alistair Headley Lindrick Common South-west 63 SK554827 60 08/12/20 Nick No fertile Yorkshire 03 Hodgetts plants, though still gametophytes present. Lindrick Common South-west 63 SK554827 60 01/12/20 Nick ca. 1000 fertile Yorkshire 04 Hodgetts plants. Lindrick Common South-west 63 SK554827 60 16/11/20 Nick ca. 50 fertile Yorkshire 05 Hodgetts shoots. Lindrick Common South-west 63 SK554827 60 1/12/200 Nick 13 fertile Yorkshire 6 Hodgetts shoots; several dozen sterile shoots. Maltby, nr. South-west 63 SK59 - 1970 Tom - Yorkshire Blockeel Rivelin, Bell Hagg South-west 63 SK38 - 1880 A. Carr - Yorkshire Roche Abbey South-west 63 SK58 - 1970 Tom - Yorkshire Blockeel South-west South-west 63 SE50 - 1970 Tom Presumably in Yorkshire Yorkshire Blockeel Levitt Hagg area. Sprotborough, South-west 63 SE50 - May 1929 D.A. Jones, - banks of R. Don, Yorkshire F.E. Milsom nr. Sprotborough, South-west 63 SK59 - January C.A. - , nr. Yorkshire 1910 Cheetham Sprotborough, South-west 63 SK5299 50 2000 Tom > 150 fruiting Conisbrough, nr. Yorkshire Blockeel plants Sprotborough, South-west 63 SK5299 50 09/12/20Nick ca. 2000 fertile Conisbrough Yorkshire 02 Hodgetts shoots Viaduct Sprotborough, South-west 63 SK5299 50 18/12/20Nick ca. 2000 fertile Conisbrough Yorkshire 03 Hodgetts shoots Viaduct Sprotborough, South-west 63 SK5299 50 24/11/20Nick ca. 3500 fertile Conisbrough Yorkshire 04 Hodgetts shoots. Viaduct Sprotborough, South-west 63 SK523994 50 14/12/20Nick 3 fertile shoots; Conisbrough Yorkshire 05 Hodgetts scattered sterile Viaduct shoots Sprotborough, South-west 63 SK523994 50 8/12/200Nick ca. 500 fertile Conisbrough Yorkshire 6 Hodgetts shoots; > 1000 Viaduct sterile shoots Sprotborough, South-west 63 SK526993 50 2001 Tom ca. 100 fertile Conisbrough, Yorkshire Blockeel plants. Nearcliff Sprotborough, South-west 63 SK528099 50 2004 L. Hill, B. New population Conisbrough, Yorkshire 69 Davies & R. Nearcliff Hoskin Sprotborough, South-west 63 SK526993 50 26/01/20Nick ca. 50 fertile Conisbrough, Yorkshire 04 Hodgetts shoots, ca. 100 Nearcliff sterile shoots. Sprotborough, South-west 63 SK526993 50 24/11/20Nick ca. 300 fertile Conisbrough, Yorkshire 04 Hodgetts shoots; ca. 1000 Nearcliff sterile shoots. Sprotborough, South-west 63 SK528099 50 30/01/20 Tom >300 fertile Conisbrough, Yorkshire 69 05 Blockeel shoots. Nearcliff Sprotborough, South-west 63 SK526993 50 14/12/20Nick ca. 200 fertile Conisbrough, Yorkshire 05 Hodgetts shoots; ca. 1000 Nearcliff sterile shoots Sprotborough, South-west 63 SK526993 50 8/12/200Nick ca. 100 fertile Conisbrough, Yorkshire 6 Hodgetts shoots; 500- Nearcliff 1000 sterile shoots Sprotborough, South-west 63 SE5300 - 22/05/19YNU - Levitt Hagg Yorkshire 65 recorder Sprotborough, South-west 63 SE537009 50 15/9/199BBS - Levitt Hagg Yorkshire 1 Sprotborough, South-west 63 SE534004 50 2000 Tom Levitt Hagg Levitt Hagg Yorkshire Blockeel (trackside). (trackside) >200,000 shoots Sprotborough, South-west 63 SE534004 50 09/12/20Nick Levitt Hagg Levitt Hagg Yorkshire 02 Hodgetts (trackside). ca. (trackside) 20-25,000 fertile shoots Sprotborough, South-west 63 SE534004 50 18/12/20Nick Levitt Hagg Levitt Hagg Yorkshire 03 Hodgetts (trackside). ca. (trackside) 20-25,000 fertile shoots Sprotborough, South-west 63 SE534004 50 24/11/20Nick ca. 20-25,000 Levitt Hagg Yorkshire 04 Hodgetts fertile shoots. (trackside) Sprotborough, South-west 63 SE534004 50 16/11/20 Nick >10,000 fertile Levitt Hagg Yorkshire 05 Hodgetts shoots (trackside) Sprotborough, South-west 63 SE534004 50 DecemberNick ca. 20,000 Levitt Hagg Yorkshire 2006 Hodgetts fertile shoots (trackside) Sprotborough, South-west 63 SE536007 50 2000 Tom Levitt Hagg Levitt Hagg Yorkshire Blockeel (tunnel). (tunnel) >500,000 shoots Sprotborough, South-west 63 SE536007 50 09/12/20Nick Levitt Hag Levitt Hagg Yorkshire 02 Hodgetts (tunnel). (tunnel) >10,000 fertile shoots Sprotborough, South-west 63 SE536007 50 18/12/20Nick Levitt Hag Levitt Hagg Yorkshire 03 Hodgetts (tunnel). (tunnel) >10,000 fertile shoots. Sprotborough, South-west 63 SE536007 50 24/11/20Nick ca. 2,000 fertile Levitt Hagg Yorkshire 04 Hodgetts shoots. (tunnel) Sprotborough, South-west 63 SE536007 50 16/11/20Nick >5,000 fertile Levitt Hagg Yorkshire 05 Hodgetts shoots (tunnel) Sprotborough, South-west 63 SE536007 50 DecemberNick ca. 1000 fertile Levitt Hagg Yorkshire 2006 Hodgetts shoots (tunnel) Sprotborough, South-west 63 SE538009 50 13/05/20Tom Millions of Levitt Hagg (cliff) Yorkshire 04 Blockeel shoots, nearly all without capsules. Sprotborough, South-west 63 SE538010 50 24/11/20Nick ca. 800,000 Levitt Hagg (cliff) Yorkshire 04 Hodgetts fertile shoots; ca. 4,000,000 sterile shoots. Sprotborough, South-west 63 SE538010 50 16/11/20Nick ca. 10,000 Levitt Hagg (cliff) Yorkshire 05 Hodgetts fertile shoots; ca. 4,000,000 sterile shoots. Sprotborough, South-west 63 SE538010 50 DecemberNick >100,000 fertile Levitt Hagg (cliff) Yorkshire 2006 Hodgetts shoots; ca. 4,000,000 sterile shoots Sprotborough, nr. South-west 63 SE50 - 01/05/19 T.C. "Conisbrough- Yorkshire 09 Thrupp Doncaster." Sprotborough, nr. South-west 63 SE50 - 04/05/19 T.C. "Conisbrough- Yorkshire 09 Thrupp Doncaster." Sprotborough, nr. South-west 63 SE50 - 04/05/19 W. Ingham - Yorkshire 09 Sprotborough, nr. South-west 63 SE50 - November T.C. - Yorkshire 1909 Thrupp Sprotborough, nr. South-west 63 SE50 - 08/11/19 W. - Yorkshire 13 Bellerby, J. Mennell Sprotborough, nr. South-west 63 SE50 - 17/11/19 A. - Yorkshire 28 Thompson Sprotborough, nr. South-west 63 SE50 - Septembe F.E. Milsom - Yorkshire r 1929 Aberford, nr. Mid-west 64 SE43 - 09/11/19 G. Webster - Yorkshire 00 Aberford, nr. Mid-west 64 SE43 - 03/12/19 G. Webster - Yorkshire 00 Aberford, nr. Mid-west 64 SE43 - November G. Webster - Yorkshire 1901 Aberford, nr. Mid-west 64 SE43 - 05/08/19 W.H. - Yorkshire 15 Burrell Aberford, nr. Mid-west 64 SE43 - 05/09/19 W.H. - Yorkshire 15 Burrell Aberford, nr. Mid-west 64 SE43 - 10/11/19 C.A. - Yorkshire 23 Cheetham Aberford, nr. Mid-west 64 SE43 - August D.A. Jones, - Yorkshire 1929 H.H. Knight Aberford, nr. Mid-west 64 SE43 - 16/10/19 W.H. - Yorkshire 29 Burrell Borwick-in-Elmet Mid-west 64 SE43 - 17/11/19 Unknown - Yorkshire 00 Fairburn, nr. Mid-west 64 SE42 - 16/06/19 YNU - Pontefract Yorkshire 34 recorder Garforth Mid-west 64 SE43 - February C.A. - Yorkshire 1918 Cheetham, W.H. Burrell Garforth Mid-west 64 SE43 - April 1933 F.E. - Yorkshire Milsom, W.H. Burrell Mid-west Mid-west 64 SE43 - 20/05/19 YNU - Yorkshire Yorkshire 36 recorder Newthorpe Mid-west 64 SE43 - 27/06/19 W.H. - Quarry Yorkshire 39 Burrell Parlington Mid-west 64 SE43 - 13/09/19 E.F. Noel - Yorkshire 18 Pontefract, nr. Mid-west 64 SE42 - June 1934 F.E. "Newton." Yorkshire Milsom, W.H. Burrell Tadcaster, Mid-west 64 SE44 - 29/11/19 E.C. - Smaws Quarry Yorkshire 48 Wallace

2.3.1 ENGLAND

The distribution of Tortula cernua in England is centred on the Magnesian Limestone of and North-east Derbyshire, and this is the only area in Britain where the species has been recorded recently (since 1990). In addition there are old records from Nottinghamshire, Mid-west Yorkshire and Cheshire. It is possible that T. cernua occurs elsewhere in northern England, but it is a very habitat-specific species.

Nottinghamshire T. cernua was recorded at Woodend, Shireoaks in 1946, but has not been found in Nottinghamshire since then, in spite of searching (Hodgetts & Blockeel 2001).

Derbyshire The only site for T. cernua is Steetley, a disused quarry complex south of Worksop, where it was discovered in 1946 and still occurs in quantity. This is one of the most important sites for T. cernua, with a regular occurrence of tens of thousands of fertile shoots and an estimated hundreds of thousands of sterile shoots. However, the ecology of T. cernua is such that it moves around to some extent within the site according to conditions. The population has shifted significantly over the six years of monitoring, but has not spread to elsewhere in the site, as far as is known.

Cheshire Plumley lime beds, where T. cernua was recorded in 1966, was visited by Tom Blockeel in 2000 (Blockeel 2000) and by Nick Hodgetts in 2001 (Hodgetts & Blockeel 2002), but it could not be refound. There seems little doubt that T. cernua no longer occurs at this site. Hodgetts visited several other potentially suitable Cheshire sites nearby in 2001, but T. cernua was not found at any (Hodgetts & Blockeel 2002).

South-west Yorkshire All the current sites for T. cernua except Steetley are in South-west Yorkshire. The three sites at Levitt Hagg constitute the most important area for the moss, with the trackside site regularly producing large numbers of plants, both fertile and sterile, the tunnel site performing irregularly over the years, and the recently discovered cliff site with millions of plants, though production of sporophytes changes from year to year. The two sites at Conisbrough support fewer plants: the Conisbrough Viaduct population was thought to be declining seriously in 2005, but increased again in 2006. One population at Conisbrough Nearcliff is small but has fluctuated rather little over the last few years. A new population nearby was discovered in 2004. Brancliffe Lime Works regularly produces thousands of shoots, though sporophytes fluctuate from year to year. Of the other sites, there are some old records from sites where T. cernua has not been seen for many years, and the population at Anston Quarry was apparently destroyed soon after it was discovered by spoil dumping. The record from Rivelin, Bell Hagg was probably an ephemeral occurrence on dumped lime spoil in an area that is generally geologically unsuitable.

Mid-west Yorkshire T. cernua has been recorded from several sites in VC64, but has not been seen at any of them since 1948.

Co. Durham A number of sites on the Magnesian Limestone in Co. Durham were visited speculatively in 2001 (Hodgetts & Blockeel 2002), but no T. cernua was seen. It has therefore never been recorded from Co. Durham.

2.3.2 NORTHERN IRELAND

Not recorded.

2.3.3 SCOTLAND

Not recorded

2.3.4 WALES

Not recorded.

3 Ecology & Habitat Requirements

T. cernua is very specialised in its habitat requirements in Britain, apparently being confined to disturbed, open skeletal soils over Magnesian Limestone, such as those found in quarries. The following accounts are given of its ecology:

Britain: "A ruderal of highly calcareous soil, characteristically on lime-waste and quarry-spoil. It usually occurs at the foot of spoil-heaps, by paths and in quarry-hollows, in sites which provide some protection from desiccation. Most of the localities are in or near Magnesian limestone quarries, but at one former site it occurred on lime deposited from water pumped from a colliery. There is also an old record from Millstone Grit moorland, perhaps originating from imported lime. Funaria hygrometrica and Leptobryum pyriforme have often been noted as associates. Lowland" (Hill et al. 1992).

Hungary: "...on the bank of a lake on shady alkaline soil in the Kiskunság National Park, a saline-alkaline area which is the westernmost representative of the Eurasian steppe zone" (Papp & Rajkzy 2000, reported by Blockeel 2000).

Austria: "...calcareous rock and mortared walls, with a clear preference for the latter, with several reports of abundant occurrence on walls in the vicinity of lime kilns; chiefly montane, and ascends to 2240 m altitude" (Grims 1999, reported by Blockeel 2000).

Scandinavia: "...± calcareous substrates, in rock crevices from lowlands to high up in mountains, in arctic mostly near the sea, sometimes on shores" (Nyholm 1989, reported by Blockeel 2000). It was recently discovered in southern Sweden (Västmanland) on calcareous clay/sand at a place where remains from limestone quarries in the area are deposited (Blockeel 2000).

Greenland: "...in salt marshes along salt lakes but also in sites along the sea. The kind of salinity may not be the same in these sites. Its distribution is strongly continental, i.e. inland in central West Greenland but less restricted in the High Arctic (cold desert). Sporophytes are extremely frequent" (Gert Steen Mogensen, pers. comm. reported by Blockeel 2000).

North America: "On rock or soil on or among rocks, probably always in calcareous situations" (Crum & Anderson 1981)..

T. cernua seems to show a clear preference, at least in Europe, for anthropogenic sites. It may have formerly occurred in Britain in semi-natural habitats on the Magnesian Limestone (Blockeel 2000). According to Headley (2004), the reason T. cernua persists at most of its British sites is that due to the nature of the substrate, making very difficult, if not nearly impossible, for larger mosses and vascular plants to grow. This is because the substrate is low in nutrients and very alkaline (around pH 9). There is a reduction in the availability of phosphate at pH values of 9 or more. Furthermore, the low ration of calcium to magnesium interferes with the uptake of potassium as well as resulting in possible magnesium toxicity seen in higher plants.

Headley (2004) also considers that shading by trees may have little or no detrimental effect on the growth of T. cernua, given its ability to persist at well-wooded sites., but concedes that the smothering effect of leaf litter and input of additional nutrients from the decomposing litter may have a detrimental effect. More detailed notes on the ecology and biology of T. cernua can be found in Blockeel (2000) and Headley (2004).

3.1 COMMUNITIES AND VEGETATION

Very little work has been done on bryophyte communities, but T. cernua appears to be part of a rather distinctive bryophyte community of bare soils on Magnesian Limestone. However, because the community is so dynamic it is difficult to define. The most common associates are Didymodon tophaceus and Funaria hygrometrica.

Table 2 - Associates of Tortula cernua

Species Frequency Mosses Barbula convoluta rare Bryum bicolor occasional Bryum pseudotriquetrum rare Calliergonella cuspidata rare Cratoneuron filicinum rare Ctenidium molluscum occasional Dicranella varia frequent Didymodon tophaceus abundant Encalypta streptocarpa rare Funaria hygrometrica frequent/locally abundant Hypnum lacunosum rare Leptobryum pyriforme rare Scleropodium purum rare Trichostomum crispulum occasional

Liverworts Leiocolea badensis frequent Riccardia chamedryfolia rare

Lichen Collema sp. occasional

Vascular plants Briza media rare Carex flacca occasional Festuca ovina occasional Gentianella amarella rare Poa trivialis rare Polygala vulgaris rare Prunella vulgaris rare Rubus fruticosus rare Thymus sp. occasional Trifolium repens rare unidentified grasses occasional

There are other species which occur in bare patches of soil not far from T. cernua colonies, but have not been recorded as close associates - e.g. Aloina aloides, A. rigida, Aneura pinguis, Brachythecium rutabulum, Didymodon fallax, Eurhynchium hians, E. striatum, Leiocolea turbinata, Lophozia perssonii, Microbryum curvicolle, Pellia endiviifolia, Pseudocrossidium hornschuchianum, Rhytidiadelphus squarrosus, Tortella tortuosa.

3.2 DISPERSAL AND STRATEGY

T. cernua is an autoicous, short-lived shuttle species, in the sense of During (1992). That is, the lifespan of an individual colony is probably rather short (a few years at most), and it has a high reproductive effort, producing many capsules with large (36-40 µm) spores to facilitate dispersal over a limited area close to the parent plant, where conditions are likely to be suitable. However, the longevity of individual shoots, and how often a shoot produces a sporophyte, is unknown. According to Crum & Anderson (1981), T. cernua "is self-sterile and for fruiting requires a long photoperiod (16 hours) with low temperatures in the dark cycle". From field observations it appears that T. cernua is a poor competitor, and that it favours growing on skeletal soil where the competition is low. It therefore relies on a regular turnover of soil at sites where it already occurs. It is likely to be able to colonise new sites, at some distance from existing sites, only with difficulty, because of its large spores.

3.3 HABITAT REQUIREMENTS IN THE UK - CONCLUSION

It is clear from the six years of monitoring that have taken place so far that populations of T. cernua are subject to considerable fluctuations. It is clearly very responsive to environmental conditions. Plants apparently appear and disappear regularly (although it is not easy to be sure of this, as non-fertile plants are inconspicuous). Production of sporophytes certainly varies a great deal from year to year, and from season to season - the remarks of Crum & Anderson (1981) on sporophyte production may be relevant here (see above). T. cernua is evidently a species of very new soils and a very poor competitor, so individual populations are necessarily transient. The performance of the total population within its broad area of occurrence - the metapopulation - is the most important factor in monitoring this plant.

As a poor competitor, T. cernua soon becomes overwhelmed by other mosses (notably Didymodon tophaceus on wetter ground) and coarse vascular plant vegetation if environmental conditions change slightly. T. cernua is favoured in conditions of very high alkalinity (ca. pH9), while the growth of other vegetation is inhibited (Headley 2004), but if the pH is lower, then other vegetation can take over. This means that there should be a regular turnover of 'new' soil over Magnesian Limestone, as happens at Levitt Hagg (trackside) due to the steep slope. It is also important that sites do not become too dominated by trees. While it appears that T. cernua can tolerate shade to at least some extent, the effects of leaf litter in smothering the ground and providing additional nutrients are detrimental (Headley 2004).

4 Threats

Table 3 - Summary of the threats to the survival and spread of Tortula cernua in Britain

Threat

Habitat destruction Consolidation of soil, lowering of pH and lack of 'new' soils to colonise at extant sites Competition from colonising vegetation, including trees, shrubs, ivy and coarse herbaceous vegetation

Habitat destruction The sites for T. cernua are potentially vulnerable to destruction through changes in land use such as in-filling and landscaping, as has taken place at Anston Quarry. Disused quarries in a post-industrial landscape such as that which exists in the Sprotbrough area are often regarded as eyesores that need to be 'reclaimed' for such useful functions as making more golf courses. Steetley is another site that could scarcely be considered a beauty spot, although it is of great wildlife interest generally. However, the extreme rarity of T. cernua and its restriction to such sites need to be emphasised in order to protect its populations. Another kind of habitat destruction is taking place at Conisbrough Viaduct, where trail biking is churning up the track so much that it large parts of it are no longer suitable for T. cernua. This disturbance is probably also incorporating large amounts of leaf-litter into the soil, lowering the pH and making it more organic. This, coupled with increasing consolidation of the soil that has not been churned up, and vegetation encroachment, appears to be very detrimental to T. cernua at this site. Also, the burning of a mattress at Conisbrough Viaduct has effectively destroyed some of the habitat.

Consolidation of soil, lowering of pH and lack of 'new' soils to colonise at extant sites It appears that T. cernua gradually declines as soils consolidate, accumulate organic debris and the pH gradually lowers, while other bryophytes and vascular plants increase. This is a natural process, but means that soils may have to be disturbed artificially at some sites to ensure a continuation of habitat. A turnover of soils happens more or less naturally at steeply sloping sites, but takes place less readily on shallower gradients.

Competition from colonising vegetation, including trees, shrubs, ivy and coarse herbaceous vegetation This may occur as a consequence of soil stabilisation and changes in nutrient and pH levels, as described above. A trend towards woodland is a natural colonisation process in many habitats in the absence of disturbance. This can be observed at Steetley, where birch scrub is gradually maturing into woodland, and at Levitt Hagg (tunnel), where secondary woodland is developing on the railway embankment. If allowed to continue unchecked, this will ultimately result in the disappearance of T. cernua colonies, largely because of the accumulation of organic debris on the soil. Ivy growth at Levitt Hagg (trackside) may be a threat to the secondary population. Vegetation encroachment at Conisbrough Viaduct, coupled with excessive disturbance to the track, appears to be eliminating colonies of T. cernua.

5 Management Implications

Some artificial disturbance of soils at some sites will probably be necessary to ensure the survival of T. cernua. An experimental scrape at Lindrick Common appears not to have been successful, however, possibly because the area chosen has too much organic material in the soil, and the pH is too low (Headley 2004). Larger scale management using JCBs may be more effective, judging by the large population that appeared on 'new' soil at Levitt Hagg (cliff). Headley (2004) states, "What in my opinion is needed to maintain populations of flamingo moss at any or all sites is to generate fresh exposures of lime kiln waste and the moss is likely to establish readily from spores".

6 Ex situ Conservation

Living specimens of T. cernua are held in ordinary culture and sterile culture at Kew Gardens as part of the English Nature-funded project on ex situ bryophyte conservation. The species is not yet held in cryostorage however.

7 Recommendations for Future Work

It is suggested therefore that the following recommendations be observed:

 Take whatever action is considered appropriate locally to safeguard extant sites for T. cernua.  If possible, institute remedial management at Conisbrough Viaduct.  Fell trees on embankment at Levitt Hagg (tunnel).  Continue to monitor condition of known populations every few years.  Follow up remarks in Crum & Anderson (1981) on photoperiodism and sporophyte production.  Investigate possibility of taking T. cernua into cryostorage and bulk up ex-situ stocks of T. cernua in case re-introduction is needed at some point in the future.

8 References

Blockeel, T.L. 2000. The status in Britain of the flamingo moss Tortula cernua (Huebener) Lindb. Report for Plantlife (unpublished).

Church, J.M., Hodgetts, N.G., Preston, C.D. & Stewart, N.F. 2001. British Red Data Books. Moses and liverworts. Peterborough, Joint Nature Conservation Committee.

Crum, H.A. & Anderson, L.E. 1981. Mosses of Eastern North America. Volume 1. New York, Columbia University Press.

During, H.J. 1992. Ecological classifications of bryophytes and lichens. In: Bates, J.W. & Farmer, A.M. Bryophytes and lichens in a changing environment. Oxford, Oxford University Press.

Grims, F. 1999. Die Laubmoose Österreichs. Vienna, Österreichische Akademie der Wissenschaften.

Headley, A. 2004. Biological and ecological investigations of the moss Tortula cernua (Huebener) Lindb. (flamingo moss). Report for Plantlife International (unpublished).

Hill, M.O. & Preston, C.D. 1998. The geographical relationships of British and Irish bryophytes. Journal of Bryology 20: 127-226.

Hill, M.O., Preston, C.D., Bosanquet, S.D.S. & Roy, D.B. 2007. BRYOATT. Attributes of British and Irish mosses, liverworts and hornworts. Huntingdon, NERC.

Hill, M.O., Preston, C.D. & Smith, A.J.E. (eds.) 1992. Atlas of the bryophytes of Britain and Ireland. Volume 3 Mosses (except Diplolepideae). Colchester, Harley Books.

Hodgetts, N.G. 2003. Survey & monitoring of flamingo moss (Tortula cernua) in 2002. Report for Plantlife/English Nature (unpublished).

Hodgetts, N.G. 2004. Survey & monitoring of flamingo moss (Tortula cernua) in 2003. Report for Plantlife International/English Nature (unpublished).

Hodgetts, N.G. 2005. Survey & monitoring of flamingo moss (Tortula cernua) in 2004. Report for Plantlife International/English Nature (unpublished).

Hodgetts, N.G. 2006a. Survey & monitoring of flamingo moss (Tortula cernua) in 2005. Report for Plantlife International/English Nature (unpublished).

Hodgetts, N.G. 2006b. Survey & monitoring of flamingo moss (Tortula cernua) in 2006. Report for Plantlife International/English Nature (unpublished). Hodgetts, N.G. & Blockeel, T.L. 2002. Survey and monitoring of flamingo moss (Tortula cernua) (Huebener) Lindb. in 2001. Report number 197. Peterborough, English Nature and London, Plantlife.

Howes, C.A. 2000. The flamingo moss Desmatodon cernuus (Hub.) (sic.) in the southern Magnesian Limestone natural area, with special reference to the Don Gorge, Doncaster. Unpublished draft manuscript for Doncaster Museum & Art Gallery.

Nyholm, E. 1975. Illustrated moss flora of Fennoscandia. II. Musci. Fascicle 2 (2nd edition). Stockholm, Swedish Natural Science Research Council.

Nyholm, E. 1989. Illustrated Flora of Nordic mosses. Fasc. 2. Pottiaceae- Splachnaceae - Schistostegaceae. Copenhagen & Lund, Nordic Bryological Society.

Papp, B. & Rajkzy, M. 2000. Bryophytes of saline-alkali areas of the Danube- Tisza interfluve, Hungary. Lindbergia 25: 134-139.

UK Biodiversity Group 1999. Tranche 2 Action Plans. Volume III – plants and fungi. Peterborough, English Nature.

9 Acknowledgements

David Atkinson (Lafarge Aggregates), John Blackburn (BBS), Tom Blockeel (BBS), Brian Davies (English Nature), Jenny Duckworth (Plantlife International), Matthew Gibson (Railtrack), Michael Green (Network Rail), Alistair Headley (University of Bradford), Deborah Irving (Network Rail), Doug James (Anderton Park), Tim Kohler (EN), Dave Mitchell (EN), Julian Morley (Cheshire County Council), Lesley Nel (Groundwork), Ron Porley (EN), Chris Rowlands, Mike Walton (BBS), Lindrick Golf Club and English Nature's Licensing Service.

10 Contacts

Plantlife International, 14 Nicola Hutchinson – Rollestone Street, Salisbury, [email protected] Wiltshire, SP1 1DX. Tel: k 01722 342730 Nick Hodgetts, [email protected] Nick Hodgetts Botanical Services, 55 Norton Street, Grantham, Lincolnshire, NG31 6BX Dr. Alistair Headley, [email protected] Department of Geographical & Environmental Sciences, University of Bradford, Bradford, West Yorkshire, BD7 1DP

11 Links

 British Bryological Society http://www.britishbryologicalsociety.org.uk/.

Plantlife International’s Back from the Brink (species recovery) programme is supported by: Natural England, Scottish Natural Heritage & the Countryside Council for Wales. Work on Tortula cernua is supported by;

Nick Hodgetts First draft dated 8th December 2008 Glossary acrocarp, adj. acrocarpous: a moss having the archegonia at the tip of a stem - usually easily distinguished by their tuft-like growth, unbranched or little-branched stems and capsules arising from the stem tips. autoicous: with male and female inflorescences on different branches of the same plant. capsule: the spore-containing part of the sporophyte. denticulate: minutely toothed. gametophyte: the vegetative, haploid generation of the bryophyte life cycle. lamina: blade of the leaf. mucronate: coming abruptly to a short point at the leaf apex. papillae: small, rounded protuberances on the outer wall of the cell. pellucid: clear, translucent. revolute: rolled downwards (of leaf margins). secund: pointing in one direction. seta, pl. setae: the stalk bearing the capsule in most mosses and liverworts. sporophyte: the spore-producing, diploid generation of the bryophyte life-cycle.