Big Fish With a Bigger Problem: The Yellowtail Tuna Faces Difficulty in More Acidic Oceans

by Max Breitbarth

Anthropogenic emissions of carbon dioxide (CO2) have resulted in increased concentrations of CO2 in ocean waters that subsequently result in ocean acidification. Bromhead et al. (2015) explored the effects of elevated CO2 levels on the development of yellowfin tuna, Thunnus albacares in their March 2015 Deep-Sea Research article. Tuna represent some of the largest predators in the ocean, and cover vast expanses across several of the earth’s oceans—meaning the effects of ocean acidification could have ramifications for the species and their ecosystems around the world. The researchers found that ocean acidification levels have a strong negative effect on growth, hatch time, and larval survival in the experimental trials. These findings show that future ocean conditions may reduce the survivability of this fish in the future and lead to drastic marine ecosystem changes—as well as affect fishing practices by humans around the world that currently depend on yellowtail as a main source of food. Continue reading

Economic Blues (Oceanic Ones)

by Patrick Shore

While many impacts of climate change can be physically seen or experienced, such as abnormal weather and storm patterns and glacial retraction, the unknown and vast nature of our ocean makes changes less visible and understandable. It does seem certain though that seemingly small oceanic changes such as rising sea levels and surface temperatures could have devastating impacts across the globe. These small changes can indirectly affect weather global weather patterns: snowpacks, rainfall, harvests, soil fertility, and storms. Aside from the physical impacts of ocean climate change, such as the flooding of coastal and lowland cities, the changes to our oceans could have more immediate, economic effects. Continue reading