The tide did now its flood-mark gain,
And girdled in the Saint’s domain:
For with the flow and ebb, its style
Varies from continent to isle;
Dry shood o'er sands, twice every day,
The pilgrims to the shrine find way;
Twice every day the waves efface
Of staves and sandelled feet the trace.
So wrote Sir Walter Scott (clearly an observant geomorphologist) in his epic poem, Marmion, published in 1808. When I say “epic” this is a slight understatement: the work runs to 200 pages in its modern paperback form. The story is one of the greatest disasters in Scottish history, the battle of Flodden Field (1513), where an English army inflicted heavy losses on the Scots, killing King James IV and most of his nobles. The Saint is Saint Cuthbert, his domain Lindisfarne, or Holy Island, off the coast of Northumberland in northeast England, and its style “varies from continent to isle” as a result of being cut off “twice every day” from the mainland by the tides. The island is holy as a result of its monastery, founded in the 7th century AD by Saint Aidan – Saint Cuthbert was a later abbot of the monastery.
Being subject to the whims of waves and tides, the island is surrounded by swirling sand banks and is itself largely made up of sand and dunes, as can be seen in the google earth image above, and this superb aerial view:
Lindisfarne arose as my topic this week after my attention was caught by a headline in the Guardian newspaper last Thursday that read “Dunes, drains, and ditches: Britain’s 10 most important wildlife sites revealed.” Natural England, the country’s major conservation body, had published its list of the most important refuges for our rarest species, all of them designated Sites of Special Scientific Interest (SSSIs). I was, of course, delighted to find that sand hosts one of them – the dunes of Lindisfarne. The species in question is a helleborine, the common name for a number of orchids; but the dunes of Lindisfarne host not just any old helleborine, but Epipactis sancta. As the description by Natural England notes:
Lindisfarne helleborine – Epipactis sancta
Originally thought to be dune helleborine until genetic testing revealed it was sufficiently different to be ranked separately. Only found on Holy Island, where its 300 plants make it a rarer species in the world than the panda, this endemic orchid can grow to 2ft tall and has up to 30 flowers.
Only 300 plants and rarer than the panda…. I believe that the photo at the head of this post is of Epipactis sancta, and not the common or garden Epipactis paustris, or Epipactis dunensis – it comes from The Wildflower Society, and they should know – but I must admit that they all look rather similar to me. The Society describes the helliborines of Lindisfarne as follows (the delightfully named snook is the sandy area where the causeway from the mainland meets the island):
The dune slacks of the Snook held hundreds of Epipactis palustris (Marsh Helleborine) which is actually a fairly common Helleborine in this sort of habitat but arguably the most beautiful of all. The flowers of this Helleborine will often open so you can see the structures and colours inside…
The local rarity, another somewhat duller looking Helleborine, was for many decades known to us all as Epipactis dunensis. The taxonomists revisited the Helleborine scene some years ago and relegated it to a mere variety of narrow lipped orchid: Epipactis leptochile var dunensis. This is how it is currently named in many botanical books.
There was much rubbing out and muttering amongst WFS list compilers in those dark days because adding varieties ("varz") is the special province of only elite Parnassian cohorts who claim to have seen more than 2,000 species…
In 2002 genetic work by Squirrell et al. confirmed that Epipactis dunenis at Lindisfarne was indeed sufficiently different from other similar looking Helleborines to be given species rank and therefore a name of its own. This new name seems to be accepted by practising field botanists although it doesn't yet appear on the BSBI lists as Epipactis sancta.
It was duly sanctified as the Lindisfarne Helleborine (Epipactis sancta) although it is not known whether there was an appropriate holy watering ceremony directed by the Archbishop of York. It has the additional special status of being English Endemic species.
Having noted all that about distinct genetic differences, if you were to present Epipactis dunensis alongside Epipactis sancta in a herbarium my guess is that only a few of our enthusiasts would be able to tell which was which.
A few years later, as so often happens with taxonomists, the Dune Helleborine gained promotion back to the Premier League with its old name Epipactis dunensis. All those people who had seen it and then rubbed it off their lists now added it back not knowing whether laugh, cry or wait for the next change.
So, regardless of the hand-wringing and angst of argumentative botanists, the fact remains that the sands of Lindisfarne are a refuge for one of Britain’s rarest species – a matter of some satisfaction to your humble correspondent.
And I should avoid wandering off on a totally unrelated thread, but it’s worth noting that the monastery on the island is also famous for being the origin of the Lindisfarne Gospels, some of the most exquisite examples of illuminated manuscripts from the Christian tradition. They now reside in the British Library, having been saved from the savage raids of the dastardly Vikings:
[Header image of Lindisfarne dunes by Nigel Chadwick, is licensed for reuse under the Creative Commons Attribution-ShareAlike 2.0 license. Aerial view of the island from http://www.ness-st.co.uk/holyisland.html and Northumberland Coast AONB]
Lovely how the curves in the illumination resemble the curves of the sandbars, which have a suggestion of Von Karman vortices.
Posted by: Richard Bready | March 20, 2011 at 09:49 AM