Fish Moving Poleward Fast
As climate change causes oceans to warm, tropical waters are getting far too hot for fish to handle, forcing hoards of marine fish and invertebrates to take to the poles, according to a new study.
Things are heating up so much, that fish are abandoning their current habitats at a rate of 26 kilometers (16 miles) per decade for the cooler north and south poles, according to researchers.
At this rate, large numbers of fish will disappear from the tropics by 2050.
Using the same climate change scenarios as the Intergovernmental Panel on Climate Change, researchers at the University of British Columbia (UBC) projected this large-scale shift of marine fish and invertebrates. The aforementioned rate of 26 kilometers per decade is the worst-case scenario, should the Earth's oceans warm by three degrees Celsius (37.4 Fahrenheit) by 2100.
The best-case scenario? If the Earth warms by one degree Celsius (33.8 Fahrenheit), fish would move only 15 kilometers (9 miles) every decade.
And considering that the global warming goal of 2 degrees Celsius is dwindling before our eyes, according to a recent study by the Global Carbon Project, it may be safe to say that we can expect the worst-case scenario.
Not only does this mean that tropical fish will have to adapt to new waters, but humans that depend on these populations will have to adapt as well.
"The tropics will be the overall losers," co-author William Cheung, associate professor at the UBC Fisheries Centre, said in a statement. "This area has a high dependence on fish for food, diet and nutrition. We'll see a loss of fish populations that are important to the fisheries and communities in these regions."
And these fish will likely come as an unwelcomed surprise to species already living in the Arctic and Antarctic.
"As fish move to cooler waters, this generates new opportunities for fisheries in the Arctic," added lead author Miranda Jones. "On the other hand it means it could disrupt the species that live there now and increase competition for resources."
The findings were published in the ICES Journal of Marine Science.