If the risk of losing the Great Barrier Reef wasn’t bad enough, a new study has found that climate change could have a devastating impact on the fish populations of the Pacific Islands. A new study by the Nippon Foundation-Nereus Program has found that Pacific Island Nations could lose between 50-80% of all marine species in their waters in the ocean continues to heat up.
The reason the impact is so severe is precisely because of its location. The waters in the Pacific are some of the warmest in the world, and they’re also some of the most constant – it usually feels like summer all year round.
It is because of this seasonal stability that even the smallest changes in water temperature can have such a vast impact on the marine life that resides there.
“Under climate change, the Pacific Islands region is projected to become warmer, less oxygenated, more acidic, and have lower production of plankton that form the base of oceanic food webs,” said lead author Rebecca Asch, Nereus Program alumnus and Assistant Professor at East Carolina University.
“We found that local extinction of marine species exceeded 50 percent of current biodiversity levels across many regions and at times reached levels over 80 percent.”
Not since the geological time periods has marine life in the Pacific Islands experienced such a drastic change in their environment.
Of course back then the change, while severe, was very gradual giving life the opportunity to adapt or move to cooler waters.
In the case of climate change however, things are very different.
“Additional warming will push ocean temperature beyond conditions that organisms have not experienced since geological time periods in this region,” said co-author Gabriel Reygondeau, Nereus Fellow at UBC. “Since no organisms living in the ocean today would have time to adapt to these warmer conditions, many will either go extinct or migrate away from the western Pacific, leaving this area with much lower biodiversity.”
If there is some glimmer of hope in all this, it is that with global cooperation, the harmful effects of climate change can be reduced to this part of the world.
“One hopeful point is that the extent of these changes in biodiversity and fisheries was dramatically reduced under a climate change scenario where greenhouse gas emissions were close to what would be needed for achieving the Paris Climate Agreement” said co-author William Cheung, Nereus Director of Science.