Dugong Numbers on the Rise Again in the Great Barrier Reef

Dugong Numbers on the Rise Again in the Great Barrier Reef

By Helen Nolan  June 22nd, 2017

Dugongs - or sea cows - are the only marine mammals that live mostly on plants, grazing on seagrass, which forms meadows in sheltered coastal waters. The world's largest population resides in northern Australia where their numbers are surging according to recently released aerial surveys.

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This World Oceans Day (June 8, 2017) focused on encouraging solutions towards the prevention of plastic ocean pollution with its theme of ‘Our Oceans, Our Future’. Oceans cover more than 70 percent of our earth’s surface and are home to up to two million species, including populations of dugongs throughout the southern region of the Great Barrier Reef.

Dugongs – or sea cows – are the only marine mammals that live mostly on plants, grazing on seagrass, which forms meadows in sheltered coastal waters. Dugongs grow up to three metres in length and weigh up to 400 kilograms.  The world’s largest population resides in northern Australia where their numbers are surging according to recently released aerial surveys.

Part of the reason for the boom in dugong numbers is that seagrass meadows (the herbivores’ favourite food) have revived along the shorelines after powerful Cyclone Yasi depleted the meadows in 2011. The marine plant provides ample amounts of nutrients if eaten in large quantities, which female dugongs particularly need for successful reproduction.

With this surge in seagrass comes a dugong baby boom. The Great Barrier Reef Marine Park Authority reports that out of 5,500 animals counted, 10 percent were calves, which is excellent news for a species that had been listed as vulnerable to extinction by the International Union for Conservation of Nature. Previously, the slow-moving animals were threatened by hunting but their biggest threats are now coastal development, loss of seagrass meadows and entanglement in fishing and shark nets causing them to drown.

In support of World Oceans Day, Asian nations have pledged to reduce ocean plastic pollution. Although some of the promises are not yet formalised, UN officials have praised the statement as an encouraging sign of nations taking the ocean and its problems much more seriously. Delegates from China, Indonesia, Thailand and the Philippines converged at a recent UN oceans summit to present an international move against ocean pollution.

Although there is a long way to go, Eric Solheim, the UN's environment director, told BBC News that ‘there are encouraging signs’ considering much marine plastic - ingested by birds and fish – often originates far from the sea, particularly in countries that have developed consumer economies faster than their capacity to manage waste. The Helmholtz Centre in Leipzig, Germany has reported that reducing the plastic loads by 50 percent in just 10 rivers, mostly in Asia, would reduce global plastic inputs by 37 percent.

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Positive Environment News has been compiled using publicly available information. Planet Ark does not take responsibility for the accuracy of the original information and encourages readers to check the references before using this information for their own purposes.

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By Helen Nolan

Helen pursues philanthropic endeavours that underpin her desire to care and nourish. She loves all creatures great and small and is thrilled to be writing for Planet Ark.

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