EVERY little bit helps. Research has revealed the potential value of whale poo in mitigating climate change through its recycling of iron.
Australian Antarctic scientists looking into ways to increase the amount of CO2-absorbing algae in oceans have traced the passage of iron through whale digestive systems and have found that whales take up iron when they consume shrimp-like krill.
Before commercial whaling began early last century, whales consumed about 190 million tonnes of krill per year, converting this into about 7600 tonnes of iron-rich faeces, which encouraged the growth of carbon-absorbing algae, according to Steve Nicol, of the Australian Antarctic Division.
''This monumental fertilising effort means the whales may have been responsible for recycling about 12 per cent of the current iron content in the surface layer of the Southern Ocean,'' Dr Nicol said.
''The baleen whales' faecal iron concentration is about 10 million times that of Antarctic seawater.''
He said about 24 per cent of the total iron in the Southern Ocean surface water is currently stored within krill body tissue.
''The most recent estimates of krill biomass in the Southern Ocean is 379 million tonnes, storing about 15,000 tonnes of iron.''
The research suggests increasing populations of baleen whales and krill would have a positive effect on the Southern Ocean ecosystem and improve the ocean's ability to absorb CO2.