Sundews

Drosera rotundifolia

Round-leaved Sundew

Cycling in the dark in Storm Brendan yesterday I was treated to a show of exquisite beauty. As the wind backed rain swept through the torch beam each drop was highlighted as an illuminated golden oval. The rain formed parallel lines twisting and writhing in the wind with golden droplets and scintillating bursts of red green and blue. It was better than a fireworks display and as the photons hit the retinas they reminded me of Arachnocampa luminosa, the cave dwelling fungus gnat in New Zealand, the larvae of which, trail mucilaginous strands each carrying bioluminescent sticky ‘pearls’ to attract and trap insect prey. They are beautiful but deadly.

In Rannoch our equivalent is the sundew. It grows in boggy places where nitrogen is hard to get because denitrifying bacteria have squandered the nitrates. Sundews seek their nitrogen from another source - the small invertebrates that they enmesh in sticky globules at the ends of tiny drumsticks. The ‘drumsticks’ curl over in response to touch (Thigmonasty) and the creature is dead within fifteen minutes but may take days to digest with enzymes. The assassin bug is able to resist any toxins and has evolved to be able to feed on the trapped insects.

Moulin a Vardie is a prime location for sundew but it is widely distributed throughout the Rannoch area.

There are three British species of Sundew - Great Sundew, Oval Leaved Sundew and Round Leaved Sundew. The latter is the most common.

Creative Commons - credit sarkan47

(14th January 2020)