Hampshire is a large and diverse county with a wide range of typical lowland habitats, including semi-natural woodland, chalk grassland, heathland, acid grassland, saltmarsh and coastal shingle. Some of these are reasonably rich in bryophytes, but the bryoflora of the county is greatly boosted by the New Forest, an extensive area of traditionally managed woodland, heathland and mire in the south-west of the county (wholly within VC11). Nevertheless, Hampshire’s climate is relatively warm and dry, so many species of cooler and wetter climates and are absent (even a few which occur further east in Sussex). Currently, at least 495 recognisable taxa have been reliably recorded at one time or another, comprising 3 hornworts, 121 liverworts and 371 mosses. Excluding subspecies and varieties, the total of about 487 species amounts to 46% of the British flora of 1069 species, as covered by the 2014 Atlas of British & Irish Bryophytes.
Although certain hotspots in the New Forest are relatively well-recorded bryologically, Hampshire as a whole has been rather poorly recorded in the past. Most of our bryological knowledge of South Hampshire (VC11) is based on the records of liverwort specialist Jean Paton, dating mainly from 1957-1960 when she was working at Southampton University. She also collated the records available at the time to produce the first bryophyte Flora for the vice-county, published in 1961. In North Hampshire (VC12) most past recording work was carried out by E.C. (Ted) Wallace and later by Alan Crundwell in the 1980s. After a long gap the late Rod Stern undertook a more systematic survey of VC11 between 2000 and 2008, assisted by Francis Rose and Howard Matcham. A BBS national recording meeting was held in Hampshire in 1956, and the New Forest was also visited during the Dorset meetings held in 1930 and 1977. See the links below for further details. Other contributions have come from professional habitat surveyors, especially New Forest-based Neil Sanderson, and from organised meetings of the Southern and Wessex regional bryophyte recording groups. John Norton, the current VC Recorder, has mainly covered the Gosport area in recent years and looked at some of the chalk downland sites.
The bryophyte flora of the county was published in the Flora of Hampshire (1996), written by Crundwell and Rose. Stern published the Atlas of the Bryophytes of South Hampshire in 2010, which mapped records on a 5 x 5km basis. His book also includes a facsimile copy of Paton’s Flora. A large body of data including herbarium records, Francis Rose’s notebook records and some of the records from local meetings still remain to be checked and input into the BBS database. Hampshire distribution maps have been compiled at 10km resolution on the Hampshire and Isle of Wight Bryophytes website but only serve to illustrate the large gaps in recording (or data compilation) historically. They do not yet include records made after March 2016.
The internationally important ancient old-growth woodlands, acid bogs and calcareous mires of the New Forest support many local and rare species at a county scale and nationally. Several species which occur are more at home in the wetter west and north of Britain and are sometimes well outside their main British range here. The New Forest supports the largest population of the Nationally Rare and GB Red List Endangered moss Zygodon forsteri, an epiphyte on old Beech trees. It also has significant populations in a Britain and Ireland context of several threatened/declining species, including the liverworts Pallavicinia lyellii and Fossombronia foveolata and the mosses Dicranum spurium and Hypnum imponens.
Away from the New Forest the most important habitat in the county is the Chalk, on which there are at least three quite different communities, including one on warm, exposed substrates with Fissidens dubius, Weissia spp. and Abietinella abietina and another on cooler, higher altitude, often north-facing grassland, nicknamed the
southern hepatic mat by Francis Rose, notable for the calcicole liverwort Scapania aspera. This mainly occurs at Butser Hill in VC11. Disused chalk quarries and old limestone buildings provide further niches for calcareous species, including the Nationally Rare and GB Red List Endangered liverwort Cephaloziella baumgartneri, at Netley Abbey on the south coast, east of Southampton (VC11). The Nationally Scarce moss Gymnostomum viridulum has also been recorded at this site, and more recently at Micheldever Spoilheaps (VC12).
Other recent noteworthy discoveries in the county include communities of Mediterranean liverworts on campsites in the New Forest, with Riccia crystallina and Sphaerocarpos spp. The Nationally Scarce ephemeral moss Bryum gemmilucens was also found in this habitat. In VC12 the predominantly western moss Pohlia bulbifera was found at Hogmoor Inclosure, a sandy heathland site, and the moss Sanionia uncinata was discovered new to the vice-county in willow carr at the same site (a very local species in southern Britain, though commoner in the north). Recently (in 2020) a population of the declining, GB Red List Vulnerable and S41 moss Tortula wilsonii was discovered by a coastal lagoon in Gosport (VC11). This may be the most easterly extant population in England (the only other Hampshire record was from the coast east of Lymington in 1974 and there are old historical records from Sussex and Kent). In addition to the liverworts mentioned above, other formerly rare bryophytes with Mediterranean tendencies are believed to be on the increase in the county, including Dialytrichia saxicola, recorded from three sites in VC11 in the last few years and Sematophyllum substrumulosum recorded from both VC11 and VC12. The ephemeral moss Acaulon mediterraneum was collected and later confirmed from a site in Fareham (VC11) in 2019 and may also occur in coastal areas in Gosport. This taxon may have been overlooked or be on the increase in southern Britain.
John Norton, October 2020