Research from the University of Adelaide has shown that some fish species will have higher reproductive capabilities due to larger sex organs under the more acidic oceans of the future.
Published in PLOS biologyThe researchers say that far from the negative effects expected under the increased CO2 These values in our oceans, which are forecast for the end of the century, use these changes in the underwater ecosystems to produce more sperm and eggs. You will also take better care of them and increase the chances of reproductive success.
"The warming oceans absorb about a third of the additional CO2 being released into the atmosphere through carbon emissions, acidifying the oceans, "says lead author Professor Ivan Nagelkerken of the university's Environmental Institute and Southern Seas Ecology Laboratories.
"We know that ocean acidification negatively affects many species in their behavior and physiology. We found, however, that in this type of temperate fish – the common triple fins – both men and women under ocean acidification conditions had larger gonads. This meant increased egg and sperm production and therefore more offspring. "
The team used natural volcanic CO2 Infiltrated underwater to compare ecosystems with CO levels2 this is predicted for the end of this century with fish communities living below today's "normal" CO levels2.
They found that the triple fins had no adverse effects from ocean acidification. The larger gonads had no physiological cost.
"We found that males ate more. They showed more intensive foraging with abundant prey – which was more common due to the increased biomass of algae growing under the increased CO2"says Professor Nagelkerken.
"The women, on the other hand, stopped eating. Instead, they reduced their activity to save energy and then invested it in larger ovaries.
"We also found that there were more mature men with increased CO2 and in this species, where it is the males who take care of the eggs, it means that we have more parents who care for the egg nests, which the offspring could reproduce. "
The researchers found that other, less dominant fish species did not show such an effect on reproductive performance, possibly due to their less competitive nature.
"We think it is likely that the triple fin and similar species will do very well with increased ocean acidification," says co-author Professor Sean Connell. "The study shows that some more dominant species will be able to benefit from changes in ecosystems during ocean acidification and increase their populations."