“Superfish” With Bigger Hearts Better Equipped for Climate Change
A new study reveals that salmon navigating the most arduous routes for their once-in-a-lifetime migration have bigger hearts and may be the best suited to cope with warming waters.
British Columbia’s Fraser River hosts more than 100 different sockeye salmon populations, each with its own unique and heroic migration story. But thanks to climate change, its water is becoming warmer, and that could spell doom for some of the fish.
A new study says the salmon that navigate the most arduous routes for their once-in-a-lifetime migration—up to 680 miles (1,100 kilometers) upstream with an elevation gain of 3,000 feet (1,000 meters) against raging whitewater--may be the best suited to cope with warming waters.
The Fraser River has heated up by nearly 2 degrees Celsius (about 3.5 degrees Fahrenheit) since the 1950s, and salmon migration mortalities have approached 95 percent in some populations during the warmest years.
“There are several studies showing