Whale droppings naturally fertilise surface waters with iron-rich excrement, allowing the whole eco-system to send more carbon down into deep waters, scientists believeWhale droppings have emerged as a natural ocean fertiliser which could help climate change by allowing the Southern Ocean to absorb more carbon dioxide, scientists have found.
Whales naturally fertilise surface waters with iron-rich whale excrement, allowing the whole eco-system to send more carbon down into deep waters, new research from the Australian Antarctic Division suggests.
'The plants love it and it actually becomes a way of taking carbon out of the atmosphere,' Antarctic scientist Steve Nicol said, adding the droppings appear as a plume of solids and liquids.
A larger population of baleen whales and krill would boost the productivity of the whole Southern Ocean ecosystem and could improve the absorption of carbon dioxide, blamed for global warming.
Iron is a limited micro-nutrient in the Southern Ocean, but recent experiments have found that adding soluble iron to surface waters helps promote much-needed phytoplankton algal blooms.
Iron is contained in algae in the surface waters where plants grow, but there is a constant rain of iron-rich particles falling into deep waters.
When krill eat the algae, and whales eat the krill, the iron ends up in whale poo, and the iron levels are kept up in surface waters where it is most needed.
Dr Nicol said: 'We reckon whale poo is probably 10 million times more concentrated with iron than sea water.
'The system operates at a high level when you have this interaction between the krill, the whales and the algae and they maintain the system at a very high level of production. So it's a self sustaining system.'
Dr Nicol said the idea to research whale droppings came from a casual pub chat among Antarctic scientists in Australia's island state of Tasmania. He said it was not yet known how much poo it would take have a significant impact on the Southern Ocean.
source: dailymail
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