In this month’s episode, we will focus on a topic which is rarely discussed, but of vital importance for our natural underwater world: noise pollution.
The title “Dare to Listen” is a bold one as the effects of noise pollution threaten the very early beginnings of all life on a coral reef, and noise plays a crucial part in the formation of krill.
We will also illustrate for you in words the sounds of a vibrant, live reef and the deafening silence of a dying one found in the Great Barrier Reef, Australia… so if you dare to listen, read on and explore the value of nature’s choir.
Just like humans, our sea creatures live in a world of sounds and vibrations and, like us, they rely on sound immensely. The ocean, or at least at healthy one, is a symphony of sound, and when scientists dropped hydrophones (waterproof microphones) into the sea, the sound revealed to them is exciting. It’s full of pops, crackles, clicks, bobs and more gruntles or whoops. For us who have never heard a fish communicate, it is difficult to imagine. A healthy reef has an overwhelming amount of sound. Shrimp tend to crackle which sounds like frying bacon. The sound of a healthy reef is continuous and frankly, it’s fun.
Animals orientate and communicate through sound. A study commissioned by Ocean Care showed that krill and zooplankton are affected negatively by sound. These species, though tiny, support a huge amount of biodiverse wildlife, and therefore more must b done to ensure they keep emerging and populating habitats. Researches have now found that they are indeed sensitive to noise pollution and can be affected by an airgun shot which is up to 1200m away.
Basically, too much noise will “scare” them away, or put them off certain environments, and with the krill gone, the other species will vanish too.
The importance of krill
These small crustaceans are found in all the world’s oceans and are vital as they are an important trophic level connection and find themselves at the bottom end of the food chain. This basically means that their existence supports most ocean life.
379,000 tonnes of krill make up the biomass of the Southern Ocean and over half of this gets eaten by seals, whales, penguins, squid and fish.
Krill and zooplankton migrate vertically, meaning they make their way up to the oceans surfaces, and the mass feeding on krill continues in this way by marine animals. Through the airshot study mentioned above scientists discovered that 95% of the krill do not complete their migration, therefore having a huge impact on other species.
If the zooplankton do not know where to go, the larger species will not be attracted to their usual spots like coral reefs, bays, coves, and even the deeper areas of the ocean. Furthermore, the fishing industry will be affected, which can then impact human life and consumption, so with this in mind, action needs to happen immediately and most likely will as it affects a multi million dollar industry, and cynically speaking, that is what will raise most eyebrows in parliaments.
To put it simply: no krill = no food for our ocean wildlife.
Krill can also digest microplastics under 5mm large, which they excrete back into the environment in a much smaller form. Through this, our whales and other fish also end up ingesting microplastics
If they react to an airgun shot, then they will also react to sea bed drilling, oil tankers, bigger ships etc. Deep sea mining is the latest form of massive noise pollution. It is an environmental disaster waiting to happen, and the effects of this due to noise pollution alone will be devastating. Our hunger for more natural resources has driven us to mine the sea bed, and though still in the infant stage of the industry the oceans will experience an ongoing disturbance which will have massive negative effects to where our animals are settling and thriving.
Noise Pollution and our latest species
At the Malta National Aquarium we have to deal with the effects of noise pollution on a daily basis. Just imagine the thumping sounds of hundreds of feet walking up and down our facilities and the effect the constant tapping of the glass has on our fish. Our latest species, the brilliantly named Pearly Razorfish or Cleaver Wrasse is a cool-looking wrasse which can grow up to 38cm and has a unique way of burying itself under the sand when disturbed by the noise.
Should too much noise be present in his habitat, it will fail to settle, and for will not mate.
These fish live in our sandy shores, at depths between 1m and 20 metres, but they can also live in muddy environments and in winter head for deeper seas up to 90m.
As soon as this fish hears any noise or disturbances it hides itself extremely quickly, as a defence mechanism and this tactic often saves it from its predators.
Noise Pollution: the bright side
There is a huge brightside here… unlike chemical pollution, noise can be turned off with instant effect. You switch off the noise, animals and wildlife returns quickly. Whereas chemical pollution takes decades to have the effects reversed, noise pollution’s reversal is faster, and the shipping industry has been committed to reducing noise. It is actually easy to silence ships, with modern engines, electric components and new technologies.
Watch Sonic Sea
Last summer we had the fun and the pleasure of showing the film Sonic Sea to our audience here at the Malta National Aquarium, and we did so using the power of the sun to project our movie. This super-sustainable way of showing a film is great for the environment, and this particular movie had a deep message about the importance of sounds in our ocean.
“The oceans are perfect medium for sound, two blue whales can have a conversation even if they are thousands of miles apart”.
Our impact on the ocean can be terrible as species rely on sound to travel undisturbed for ideal communication.
We are breaking down communities due to disturbances in the sea caused by our loud activities.
To shift the perspective: you wouldn’t go camping or build your home near a highway and you hate it that road works have just started on your street as the noise wakes you up at 630 am.
If we don’t like it, our fish hate it too.
Sound can be detrimental to life as it is so crucial to marine life. Check out Sonic Sea and take action here and get inspired on how silencing the noise will have an instant positive effect.
Just in: Plastic bag found at deepest point of our Oceans
If we ever needed more evidence of the extent of the pollution humans are causing to this planet using plastic, scientists have somehow found it.
This, not your typical ocean discovery, is perhaps one of the saddest. Explorers have found a plastic bag, sunk at the deepest point of the sea. The deepest point of the Earth, the Mariana Trench of the Pacific Ocean is a sacred place to researchers and yet here, even at 10,927 metres deep, plastic can now be found.
The eerie footage of Victor Vescovo’s discovery was shared by Sky News and can be seen here as viewers can see the sandy bottom and a deep sea fish, together with the pollutant. The Dallas based explorer is our deepest ever diver, so you can imagine his heart break after discovering that even at that depth, the impact on plastic can be felt. This was the third time humans have dived to the Mariana Trench, with James Cameron the last diver back in 2012. The first expedition was made by the US Navy in 1960, to a depth of 10,912 metres.
There is now an estimated 100 million tonnes of plastic pollution now found in the world’s oceans, according to the United Nations as the war on plastic intensifies.
Something to think about:
The Earth is 4.6 billion years old. Scale that down to 46 years.
We’ve basically been here for 4 hours and our industrial revolution began just 1 minute ago.
In that time: 50% of the world’s forests have been destroyed.
Half the forests in just 1 minute. It is not sustainable.
Keep doing your bit:
Of course we believe that every little counts, and we have a fun and easy way to help raise more awareness, plant some mental seeds of good will and also clean up the environments… what are you waiting for: Find those caps today and come to exchange them for entrance tickets.