The Fairy Shrimp - Just Add Water

I’m used to being disappointed. As a boy I was given a pile of American comics: The Amazing Spider-Man created by the late Stan Lee. Despite Spidey's web-slinging antics I was always more captivated by the inside back cover. There, an advert for 'sea-monkeys' showed a family of bizarre, grinning humanoid creatures which would become your pets and “bring smiles, laughter and fun into your home” if you sent away a fistful of dollars to somewhere called ‘New Jersey’. However the advert informed me that because I lived on the other side of a major ocean this offer did not apply and my childhood therefore remained devoid of the promised “smiles, laughter and fun”. I realise now that an even greater disappointment would have awaited me if I had actually ordered these creatures. In reality, sea-monkeys were simply brine shrimps, tiny crustaceans. not incredible aquatic simians.

Just like those fabled sea-monkeys, Britain’s fairy shrimp are also crustaceans from the order Anostraca. They have transparent bodies, antennae, blobby black eyes on stalks and twenty-two leaf-like legs which propel them, upside down, through water. They’re positively prehistoric-looking and haven’t bothered to evolve much since the Triassic period 200 million years ago. It’s amazing they have survived so long. Unlike other crustaceans, such as crabs and woodlice, fairy shrimp do not have hard exoskeletons. This armour-free existence leaves them vulnerable and they can only survive where nothing will eat them. But where on earth can you find such a habitat on our hostile planet? Safe, predator-free homes don’t just fall out of the sky.

As rain falls, it transforms the ruts, ditches and depressions of our world into puddles and these puddles are a freshwater fresh start for life. The fairy shrimp are the first settlers in this safe new world. But how do they get there? The spooky truth is they have always been there. Like The Amazing Spider-Man. the fairy shrimp have their own superpowers. Their eggs can lie desiccated and dormant in the soil for years, even decades. They are resurrected by water; the Pot Noodles of the animal world. There are legends of 100 year old Anostraca eggs taken from museum shelves, wetted and awakened. One tale even tells of eggs carbon-dated at 10,000 years old being resurrected.

It’s a long, dry wait down there in the earth but, when rain arrives, the pool party starts. Newly formed puddles teem with fairy shrimp but puddles are only temporary accommodation. To adapt, fairy shrimp have a fast life cycle; a race to produce more eggs before their home dries and disappears. Unsurprisingly, fairy shrimp are incredibly rare and hard to find; you’re more likely to encounter some actual fairies. But if you’re out hiking on the South Downs over the New Year and are looking to make a new start in 2019, keep checking those puddles. You may find some other animals trying to make a new start too.