Originally published September 2012
Hello everyone! I hope you all survived the endurance test that we Brits like to refer to as Summertime. Our woodland walks transformed from the kind of mud-ridden pathways Her Majesty’s Marines are forced to slide around by sadistic Sergeant Majors to the sun-baked, rock-hard tracks usually found on Greek islands, and back again, with startling rapidity! Despite our decidedly homocentric aversion to inclement weather, we had only to look around to see how our fauna and flora flourished during those extended periods of non-stop Summer rain. The trees practically glowed with green vitality, the feathered folk were out in abundance ‘tween showers and the number of foxes, badgers, rabbits and deer on the lanes at night was certainly indicative that Ma Nature’s regime was going to plan. Our rather soggy start to the season also meant that Quarry Wood is now looking stunning with an unusually full, though overgrown, pond as it’s centrepiece. The Dragons and Damsels are still ‘hawking and darting’ over the water like bejewelled Will O’ the Wisps and the magnificent fronds of the wild fernery are reflected on the surface to produce a decidedly Dali-esque vista; and not a melting clock in sight!
Whilst we are still in holiday mode, let us have an end-of-Summer show of hands. What image does the name Crustacean conjure up? The culinary inclined may dream of Lobster Bisque, Dressed Crab or even a prawn Cocktail, whilst Aquatic ecologists will picture vast swarms of Krill being hoovered up by huge Baleen Whales. How many people would think of the most successful terrestrial Crustacean boasting more names than the Scarlet Pimpernel? I refer to the ubiquitous Woodlouse of the Order Isopoda (from Greek, iso– same and poda-foot).
Currently, up to forty-six species of Woodlouse are present in Britain though the number of native species varies between thirty-two and thirty-five depending on which criteria you use. Marine ancestors of this familiar little bug can be found in the fossil record as far back as the Carboniferous Period (around 300 million years ago). However it appears that they only ventured onto land a mere 50 million years ago. This was obviously a beneficial move for the creatures as the number of known woodlouse species globally is just under 4,000. The sea shore, being a kind of half-way house, is still inhabited by numerous not-so-distant relatives of the terrestrial species, such as the Sea Slater (Ligia oceanica). This relatively short evolutionary step from aquatic life may well be the cause of the main problem Woodlice face on land, that is to maintain their fluid balance. Unlike most insects they do not have a waterproof cuticle and dehydration is a constant threat. They appear to have overcome the problem through a series of behavioural responses. The greater the humidity, the slower a Woodlouse will move. They also move away from light and generally rest in damp, dark and confined spaces in order to minimise water loss by evaporation.
As with many Crustaceans Woodlice grow throughout their lives and need to shed their armour-plated exoskeleton periodically. Uniquely (as far as we know) in the animal kingdom they shed it in two stages. The rear half is shed several days before the front half, thus cutting down on the time when the bug is at it’s most vulnerable to predators. These are many and varied, from spiders, centipedes and beetles to owls, toads and shrews. As in the case for Earthworms, numerous Woodlouse-based recipes abound so as to keep the Survivalists sector happy. In fact a gentleman by the name of Vincent Holtz produced an interesting book titled Why not eat insects? as long ago as 1885, in which he argues the case for throwing together a tasty Woodlouse Sauce!
I have been carrying out research on various plants and animals for many years now and I have come across a phenomenum that I can only attribute to one lady, Enid Blyton. Not a penchant for wearing pointy hats with bells on the end but rather the widespread practice of categorising the most prestigious, unusual or common species in a given group as the ‘Famous Five’. So we can now look up the Famous Five African game animals, the Famous Five species of Wrasse in UK waters and yes, the Famous Five species of Woodlouse native to Britain. These being Philoscia muscorum (common in grass and hedgerows), Trichoniscus pusillus (just common!), Oniscus asellus (found in damp, rotting wood), Porcellio scaber (unusually for a woodlouse prefers dry walls and gardens) and the well known Pill Bug (Armadillidium vulgare). The Latin name of the latter species gives us a clue as to to how it defends itself; just like it’s South American namesake it can roll up into a pill-shaped ball. Not only do they resemble pills in appearance but were commonly prescribed in popular medicine for indigestion and other gastric complaints!
Like most of the animals of the leaf litter and dead wood, Woodlice play an important part in breaking down dead plant material and recycling nutrients. In addition to consuming leaf litter, fungi, algae and carrion these armoured bugs are not averse to cannabilism when needs must. They also consume their own faeces in order to obtain every nutritional scrap the second time around. Woodlouse cracker anyone?
The association with food is evident in their common names around the country. These include Cheese Bug and Cheese Log in Kent and Berkshire respectively. In the west country they are associated with pigs. Chucky Pig, Sow Bug and Gramersow are just a few of the monikers this remarkable little denizen of our woodlands, fields and homes is known by. Whatever your choice of name, take a stroll in the woods and spare a thought for the fourteen legged, armour-plated louse who stepped out of the sea and into our lives!
Be gone foul Slater, get thee hence! Goodbye!
I banish you forevermore, forever from my sight.
Dare not leave your homes by day, restrict yourselves to night.
And if I see you wearing colour, anything but grey,
I swear to God almighty, you will not survive the day.
Paul Hughes 2010
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Image 1: Bichito Bolita sobre Hoja by Gustavo Fernando Duran, used under Creative Commons License 2.0 / Image 2: Woodlice by Woodlouse, used under CC2.0 / Image 3: Big pillbug-3 by Susannah Anderson, used under CC2.0