From the tiniest zooplankton to the largest blue whale, our oceans are filled with amazing marine life, and what better time to celebrate it than World Oceans Day?
What is World Oceans Day?
Started by The Ocean Project in 2002, World Oceans Day is celebrated across the globe. With around 71% of the earth’s surface covered in water, the oceans are vital to the health of our planet and much of what we do has an impact on them. World Oceans Day aims to raise awareness of our oceans and most importantly our need to conserve them, for ourselves and for the diverse range of marine life that call our oceans home. Every year World Ocean Day is centred round a different theme and this year’s is Our Ocean, Our Future and one of the main focuses is spreading the word about plastic pollution. Plastic is everywhere and our oceans are no different with everything from tiny microplastics working their way up the food chain to large pieces of discarded plastic littering our environment and causing a risk to animals that can become tangled. Want to make a difference and help clean up the oceans? Always put your rubbish in the bin, recycle where possible and why not take part in a beach clean?
Find out more about world oceans day here – www.worldoceansday.org/.
Marine wildlife
With around 230,000 marine species, and more yet to be discovered, our oceans are brimming with life. Life under water can be a challenge though, and animals have found fascinating ways of adapting, surviving and thriving in their watery world; here we celebrate just some, but why not check out our Animal A-Z to learn about more?
Blue Whales – the largest animal in the world
It is difficult to talk about marine life without mentioning the blue whale. Reaching almost 30 m in length, it is largest living creature in the world, and like us, they are mammals, so must surface regularly to breathe air. Interestingly, despite their large size, blue whales feed on one of the smallest marine animals – a tiny crustacean known as krill – and in summer can consume between 900–4100 kg a day. Blue whales are mysticetes, also known as baleen whales, so lack teeth. Instead they have plates of baleen that act like a sieve and filter krill out of the water.
Box jellyfish – the most venomous marine creature
Jellyfish in general are famous for their ability to sting, but not all jellyfish have stings strong enough to hurt humans; in fact, visit Palau in the Pacific Ocean and you can swim in an ocean filled with jellyfish without getting stung once. However, some jellyfish are venomous, and none are more so than some species of box jellyfish. With each tentacle containing 5,000 stinging cells and venom that attacks the heart and nervous system and can kill a human, box jellyfish are certainly a species to avoid. However, jellyfish don’t intentionally go for humans; the sting and venom are meant for prey, and immobilise them before they have a chance to struggle and try and escape, which would ultimately end up damaging one the jellyfish’s delicate tentacles.
Mimic octopus – King of camouflage
Hiding from predators and prey is always beneficial and camouflage is a popular method, with many sea creatures adopting the strategy. But, few better than the mimic octopus, which can change its colour to suit the environment it is in. It is certainly not the only colour changing species – other octopuses and cuttlefish do as well – but the mimic octopus has another trick up its sleeve as it can change shape, and take on the appearance of other species. Taking on the appearance of your prey or yours preys dinner is massively beneficial, as you can wait for your dinner to come to you.
Clownfish – Living in harmony with other species
Clownfish, the beautiful orange and white tropical fish made famous by Finding Nemo, live in an anemone, but have you ever wondered why? The answer is mutually beneficial symbiosis, and it is not uncommon in the animal kingdom. What that means is that both the clownfish and the anemone benefit from the close association and are dependent on each other for survival. Most fish can’t call anemones home because they are unable to suffer the sting, but clownfish have an extra thick layer of mucus to protect them. But, what’s the benefit to that? Well, the anemone offers the clownfish protection against predators, and likewise the clownfish scares off fish that would otherwise predate on the anemone. Clownfish also provide a cleaning service, and their waste nutrients for the anemone.