As oceans warm, coral reef fish might prefer to move rather than adapt

Date: October 5, 2016

Source: University of Texas at Austin

Scientists have new evidence that coral-reef fish -- who are capable of adapting to warmer temperatures brought about by global climate change -- will probably opt instead to relocate to cooler parts of the ocean.

In experiments using a fish found in coral reefs around the world, the blue-green damselfish, Chromis viridis, researchers found that the fish were capable of adapting to living in water 2-4 degrees Celsius above their normal summer temperatures; however, when given the slightest chance, the fish moved to cooler water.

"When fish have to adapt to increased temperature, there are physical consequences. They may not be able to handles stress, or reproduce, or even grow," said marine scientist Dr. Jacob Johansen from The University of Texas at Austin. "But, when they seek out temperatures that they've evolved to be in over thousands of years, they can mitigate the impact of increasing temperatures and not sacrifice critical physiological processes."

Johansen and fisheries biologists from the University of Copenhagen and James Cook University collaborated on the study, published in the journal Global Change Biology.

Marine fish are faced with a tough decision. The ocean is warming at a faster rate than occurs on land, because oceans operate as sinks -- trapping in the heat. Many ocean fish will need to adapt or move to avoid death.

Continued

Warmer Temperatures Help Malaria Reach Higher Altitudes

March 7, 2014

redOrbit Staff & Wire Reports – Your Universe Online

Scientists from the London School of Hygiene & Tropical Medicine and the University of Michigan have discovered the first concrete evidence that the mosquito-borne disease malaria travels to higher elevations during warmer years and returns to lower altitudes when temperatures become cooler.

In research appearing in the March 7 edition of Science, the study authors reviewed records from the highland regions of Colombia and Ethiopia to see what impact climate change had on the global incidence of the ailment, which infects a reported over 300 million people annually.

Their findings reveal that, without improved monitoring and control efforts, malaria cases in some of the most densely populated regions of Africa and South America will increase significantly as the planet’s temperatures increase in the years ahead – effectively bringing the disease to areas that have traditionally faced a low risk of infection.

Read more at

Warming Temperatures Cause Aquatic Animals to Shrink the Most

ScienceDaily (Nov. 5, 2012) — Warmer temperatures cause greater reduction in the adult sizes of aquatic animals than in land-dwellers in a new study by scientists from Queen Mary, University of London and the University of Liverpool.

The research published Nov 5 in Proceedings of the National Academy of Sciences (PNAS) shows that the body size of marine and freshwater species are affected disproportionately by warmer temperatures. This could have implications for aquatic food webs and the production of food by aquaculture.

The researchers compared the extent to which the adult size of 169 terrestrial, freshwater, and marine species responded to different non-harmful temperatures, in the largest study of its kind.

Summarising the results, co-author Dr Andrew Hirst from Queen Mary's School of Biological and Chemical Sciences, said:

"Aquatic animals shrink 10 times more than land-dwellers in species the size of large insects or small fish. While animals in water decrease in size by 5 percent for every degree Celsius of warming, similarly sized species on land shrink, on average, by just half a percent."

Continued:  http://www.sciencedaily.com/releases/2012/11/121105151334.htm