Today is Earth Hour – a worldwide movement that symbolises a commitment to protect our planet. It brings awareness to environmental issues and the challenges we face to create a sustainable world. Our commitment to the Earth extends beyond that and involves recycling, shopping second hand, turning the lights off when we leave a room and getting our greens from the vegetable garden.
Earth Hour started in Sydney in 2007 and it has since spread to thousands of cities and towns around the world. It’s held annually in March, and all you have to do is turn your non-essential lights off for an hour between 8:30pm and 9:30pm local time.
The focus of this year’s Earth Hour is on the places we love. Of course, the Great Barrier Reef is a well known and beautiful place that is affected by climate change, but we’re going to spread our love for Shark Bay, located on the westernmost shores of Australia.
Recognised by UNESCO as one of the most remarkable places on earth, Shark Bay has three important natural features that make it special – its enormous seagrass beds, which are one of the largest meadows in the world, the dugong population that feed on the seagrass, and the stromatolites, prehistoric living fossils that we were privy to witness during our visit there.
Shark Bay is also home to five species of endangered mammals, including the Burrowing Bettong, which is now classified as Near Threatened, and the seagrass meadows also provide food for the Green Turtle and Loggerhead Turtle, both endangered.
Climate change can disrupt the ecosystem at Shark Bay by raising the temperature of the water. A disastrous event like this has already happened, when in the summer of 2010-2011, the average temperature of the water was 5°C higher than normal. Because the seagrass at Shark Bay is temperate, not tropical, 90% dieback was recorded in some areas of the bay during this heatwave.
Because the seagrass is a major source of food and habitat to the animals in Shark Bay, this change in the ecosystem produced a snowball effect. Animals that rely on the seagrass decreased, and therefore the predators that feed on them also suffered. Seagrass is also important to maintain banks and sills in the bay, which reduce circulation and maintain a salinity gradient that is required to sustain the stromatolites.
See, our environment is a fragile thing and our planet is a precious place. It is, after all, the only place we have to live, so let’s take care of it, and show our commitment by turning our lights off tonight.