The weekly photo challenge this week really got my underwater brain going. I have had so many ideas bouncing around in my head that I just couldn’t resist giving a second perspective on being ‘on the move’. So I bring you….the sea cucumber!
My first take on the theme was schooling bigeye trevally. They are big and fast, seeking safety by whirling together in big numbers. Which is in stark contrast to the slow and solitary sea cucumber. Despite its name it is not a vegetable, and yes, it does actually move! Although sea cucumber life is definitely life in the slow lane. They are detritus feeders, found on the seabed. And to the uninitiated, the easiest way to tell top from tail is to look for the tell-tale waste trail found just behind the sea cucumber as he slowly (oh, so slowly!) inches along to find his next meal, leaving the remains of his last one behind. Not the most glamorous of marine life!
With speed not an option, sea cucumbers have developed a bizarre evolutionary defence mechanism. When stressed, over-heated, or under attack they eviscerate their internal organs, often accompanying that with a squirt of toxic chemical solution for good measure. Fooling your predator into enabling your not-so-speedy getaway by offering them an easy meal and then intoxicating them, thus slowing down their pursuit. An interesting defence mechanism if ever there was one! And it may have worked very successfully for sea cucumbers for hundreds of years. But it seems that for sea cucumber populations today, that particular party-trick is no match for rising consumer demand for sea cucumber, and their subsequent over-fishing.
In Asia there is a huge market for sea cucumber, worth a staggering £35 million. Sea cucumber is valued as both a delicacy at the dining table and for its reputed medicinal properties in traditional medicine. They are also a hot favourite currently in cancer research. But the pressure on some species of sea cucumber is really beginning to show. The IUCN Red List, which evaluates the conservation status of plants and animal species around the world, currently records 16 species as threatened.
I see shelves and shelves of sea cucumber for sale in shops and airports all over South East Asia. I used to see shark fins for sale on all the same shelves. Thankfully, with the growing awareness of the damage done by the shark fin trade I am seeing less shark fins on shelves. But that just leaves more room for the sea cucumbers. I find it so frustrating that we seem hell-bent on pushing our oceans and the species within them to the very brink before realising our mistake and trying to scrabble back from the precipice.
Although they may not be as beautiful or attention grabbing as a shimmering cloud of reef fish, or as thrillingly majestic as a shark cruising through the blue, they are still a vital part of our ocean ecosystems. As bottom feeders they are key members of the cleaning crew of the oceans, recycling nutrients on the reef and preventing ocean acidification.
I’d like to think that global awareness will kick in before we lose sea cucumbers altogether from our oceans. But with my pragmatic head on, I recognise that it’s probably unlikely. I’m sadden by the reality of our consumerist and conservationist apathy. They may not be the coolest kid on the block, but the oceans – and our planet – really would not be the same without them. And if they do have the cancer fighting powers that scientists are investigating, then they deserve our attention as a resource which we should be looking to protect. Before we lose them.