Beware the Bladderwort, my son!

Bladderworts feed on insects

Bladderworts use an intricate mechanism to feed on insects. And they’re not the only carnivorous plants in the Purbeck wetland heaths.

The innocent looking Bladderwort plant might not have ‘the jaws that bite and the claws that catch’ of Lewis Carroll’s fearsome Jabberwocky but don’t be taken in by its sweet little yellow flowers for an instant - it can trap an insect in one ten thousandth of a second.  

Study Utricularia under a powerful microscope and you will be treated to one of the most complicated mechanisms for catching prey in the natural world. When an unsuspecting invertebrate unsuspectingly alights on its ‘trigger’, it activates an underwater process that sends air from one part of the plant to another, sucking the doomed creature in. 

Plants feed on insects

Bladderworts aren’t the only carnivorous plants in Purbeck’s extraordinary wetland heaths. The Sundew family, often described as ‘living flypaper’, use glandular hairs on their leaves to generate sticky traps powerful enough to stop butterflies and dragonflies in their tracks. The ingenious Drosera wrap themselves around the victim to slowly enjoy the feast. Self-pollinating Butterworts, more prolific on northern moors, grow here too – look out for single pale flowers radiating from an olive-green star. 

Intrigued? Then head, with a good set of eyes, for Godlingston Heath or Heartland Moor, two wetland hotspots for all three of these plant families. Top of the tick list really ought to be the Godlingston Sundew, a hybrid species that was first discovered here. This rarity produces such a profusion of closely tangled red leaves that you even stand a fighting chance of spotting one from a distance.

Vital role played by peat

Ecologist David Brown from the National Trust says: “Mire communities are hugely important habitats so we need to know every detail of life here. The bog mosses, or Sphagna to give them their scientific name, support a vast array of wildlife, but when they die, they only partially decompose in the cold, acidic water. The result is the formation of peat, and as layers of peat build up, they become one of the best solutions we have for locking up carbon.”
Historically, heathland was grazed by livestock but 20th century farming methods unfortunately reversed that. A detailed study carried out in Purbeck more than a decade ago showed that in the absence of wandering cattle, the invasive Purple Moor Grass had taken over many of its mires, smothering the important stuff. 

The Trust responded by, among other things, buying its own herd of Red Devons. And after years of working with other landowners, a local grazier and a few ponies, results are good. 

" Nothing happens overnight and you can’t accelerate natural processes but we resurveyed the wetlands last year and there has been real progress. The unwanted grasses are in check, the mosses are growing and the carnivorous plants are thriving."
- David Brown, Ecologist

Additional facts: 

  • Peat bogs are high in acidity and therefore good at preserving things for thousands of years. Precious manuscripts, human bodies and historically important artefacts have all been discovered in peat bogs in the UK
  • Sundews were used as cough medicine in the 12th century 
  • There are 220 species of Bladderworts, 194 of Sundews and 80 of Butterworts 
  • Sundews have a lifespan of up to 50 years 
  • The bladderwort is 100 times faster than the Venus Flytrap at catching its prey
  • The Industrial Revolution, powered by coal, killed off great swathes of Britain’s precious peat bogs  
  • Britain’s bogs are so damaged, they are estimated to emit as much carbon per year as the entire British transportation system; likewise, if they were restored, they would sequester as much carbon again.