This was originally published in ‘The Nerve’ the Southampton Biological Society Paper:
Global warming has had wide ranging affects on the environment and life on this planet. From the shrinking of the icecaps to the death of forests due to acid rain, very few places have not felt some sort of impact. One of the lesser known effects is increasing ocean acidity. The first sign that the rise in ocean acidity could affect animal behaviour has just been documented by the National Academy of Science in the US.
This study looked at the effects ocean acidity has on the ability of orange Clownfish larvae (Amphiprion percula) to find a suitable habitat. The habitat chosen by Clownfish larvae is thought to be closely linked to the smell organisms in that habitat give off. The larvae are attracted to scents of tropical tree plants and are repelled by the smell of swamp tree plants, as well as the smell of their parents. This results in Clownfish larvae selecting a habitat which gives adequate predator protection, a good supply of food and also prevents inbreeding.
This ability to pick out the most suitable habitat was put to the test in studies involving sea water containing the current levels of acidity and the predicted levels of ocean acidity in 2100. The results showed that although the larvae were still attracted to the tropical tree plant odours in water exhibiting the 2100 levels of ocean acidity, they were no long repelled by the swamp plant odours or the odours of their parents. If this trend were to become commonplace, the number of larvae making it to adulthood would drop significantly due to larvae perishing in the swampy environments.
It remains unknown why increasing ocean acidity accounts for this loss of appropriate habitat selection, but these results suggest that life may become far less amusing for the Clownfish in the future.