Vitrealis : Early Spider Orchids on the Purbeck cliffs

Tuesday 16 April 2024

Early Spider Orchid Orchis sphegodes - Purbeck, Dorset

The Early Spider Orchid, symbol of the Dorset Wildlife Trust (although they seem to favour the generic Wildlife Trust Badger these days), is one of the star plant species of Dorset's beautiful Purbeck coast - a chunk of limestone jutting out into the English Channel between Swanage and Weymouth. My destination today was Dancing Ledge, a popular spot where (with a bit of scrambling) you can reach a small swimming pond cut into a rocky ledge just above the waves.

Purbeck Cliffs at Dancing Ledge, Dorset (near orchid site)

I should come clean - I had travelled to Dancing Ledge to look for Puffins, which are just about maintaining a breeding foothold in Dorset here. Typically, none were around. But the Early Spider Orchids more than compensated. They have a patchy distribution in the UK (see map from the National Biodiversity Network here), and are largely restricted to calcareous soils in Dorset, Sussex, Kent and the Brecks of East Anglia. In the UK, Early Spider Orchid is classed as 'nationally scarce', and is protected under the Wildlife and Countryside Act 1981. Fortunately, there were plenty around on the grassy slopes above Dancing Ledge: I saw at least a hundred spikes, many of which are right next to the steps that descend from Spyway Barn to meet the coast path. (If it was rarer, I wouldn't be doing a blog about it!) Nevertheless, I was careful to check that I wasn't flattening any when I took these photos. Late April is peak Early Spider Orchid viewing season down here; most will have gone over by late May.

Early Spider Orchid spike Orchis sphegodes - Purbeck, Dorset

The flowers are meant to resemble a spider, but to me they have more the look of a furry bumblebee albeit with a lilac 'H' mark on a darker background. They are in fact pollinated by bees, but by mining bees (Andrena species) rather than bumblebees. Early Spider Orchids look very much like the closely related Bee Orchid Ophrys apifera (same genus), although that has pink 'wings' (strictly outer tepals) rather than light green.

For the sake of comparison, here is a photo of a Bee Orchid (below) from Powerstock Common, Dorset, taken in June 2015. Bee Orchids flower much later than Early Spider Orchids (June to July), and have a widespread distribution across the UK.

Bee Orchid Ophrys apifera - Powerstock Common Dorset (June 2015)

There is also a Late Spider Orchid Ophrys fuciflora, which has a wider central lobe and pink (not green) tepals. As the name suggests, it flowers later than its early cousin (June to July). However, it is extremely rare in the UK, being restricted to east Kent. I have never seen one, but there are some nice images on a blog post by Martin Peacock (link here).

I'll leave you with a last look at another Early Spider Orchid spike from Dancing Ledge.