Last week Tim and Helen at SBC Parks department spent two days out on Scarborough’s North Bay surveying a site fondly called ‘the orchid terrace’. As its name implies, this steep grassy slope above and behind the North Bay beach huts, Scarborough is a local hotspot for orchids of several species, and a beautiful setting for a coastal meadow, just within hailing distance of the families and school parties squealing and splashing in the gentle lapping waves on the beach, yet apparently inaccessible, its lower edge shored up by the retaining wall built behind the row of beach huts on the North Bay promenade.
The name orchid terrace is pretty apt. Pyramidal Orchid (Anacamptis pyramidalis), the most abundant species of the three species present numbered almost four thousand flowering spikes, around 600 Common Spotted Orchid (Dactylorhiza fuchsii) and 100 Bee Orchids (Ophrys apifera) in flower. a sum total of approaching 4000 flower spikes of three different orchid species were counted this year within a fenced area which notionally defines the site. The survey area, perhaps a quarter of a hectare, by no means encompasses all of the extent of orchid-bearing grassland habitats on the North Bay but the summer count from the fenced terrace, a total of eighty transects of approximately two metres width, has become a valuable data set on the variable fortunes of the orchid population. It has been surveyed annually for the past nine years or so by local amateur botanist and geologist Peter Robinson. (There are tell-tale transect numbers painted on the fence posts of the lower boundary, corresponding to green twine markers on the top fence line.) Peter’s counts have shown remarkable variability in the counts from year to year and species to species, and now that the data set and time frame is large enough he is contemplating publication of his study so far in a journal such as British Wildlife.
This year, Peter was very much looking forward to the count again and to having some assistance from younger-legged people. Alas in the optimum week (when all three species are in flower) he was unwell so Helen and I undertook the count following his instructions. His counting method divides the entire area into transect strips 2m wide up and down the slope. Stringing out the transect boundaries and then counting calls for a great many return journeys up and down the steep slope. Peter worked out that last year his full distance climbed was equivalent to climbing a Scottish Munro, (3000 ft mountain) and so takes considerable stamina. Certainly after carrying out half of the transect counts on day one, albeit split between two of us the calf muscles were feeling it!
We were fortunate on the second survey day to have some help from Lin Hawthorne (one of Tim’s twitter friends, @Haggewoods, should you like to follow her, and I’d recommend you do), who came across to Scarborough to appreciate the orchid site (and sight) and we got a good system going to mark out and count three transects at a time. Our peak in a single transect was 124 pyramids, although eclipsed by the strip just below the lower fence. This is counted as transect number 90 and takes the prize for the greatest abundance of orchids, with 66 Bee, 118 Common and a whopping 1170 pyramids in this precipitous strip of stony scree soil perched above the rooves of the beach huts.
Next year when we put out a call for volunteers to help with the count in June or July – this year was a couple of weeks later flowering – you will know what site I’m referring to. Perhaps you will consider coming out with a packed lunch to help us count. We also need to do some winter management, to strim and rake off the vegetation which is getting rank in places and risks swamping the orchids. There are some gorse bushes establishing too which need to be removed if the grassland is to stay in good condition for its botanical riches. There may next year be a call to conduct a more detailed vegetation survey of the flora growing in association with the orchids, which has not be studied since the first year of the count and may reveal some interesting dynamics on the site.