Recreational fishing has had a gangbuster season in San Diego, thanks to the presence of tropical fish not normally found in those waters, like the bluefin tuna shown here. Photo by Point Loma Sportfishing.
Over the last few years, the waters off the West coast have been warming to about 4 to 5 degrees fahrenheit above average. This might seem like a small change, but it can cause major changes in the coastal ecosystems. The warm water, which scientists have nicknamed “the Blob,” formed two years ago near Alaska and has spread down the West Coast and is especially evident in Southern California. With the warmer waters, tiger sharks, hammerheads and even tropical sea snakes have moved northward.
The map of the West coast “Blob’ shows how much above (red) or below (blue) water temperatures were in 2015 compared to the long-term average from 2003 to 2012. Photo by Nasa.