Thanks to El Nio, California's coastal waters have become more suitable for fish from the tropics (热带地区) to live.Hammerhead sharks are among them.
“For over a year now, a lot of warm water fish that we don't usually see have been coming up，” said Rick Feeney, fish expert from the Natural History Museum of Los Angeles County.
The arrival of large numbers of big fish like wahoo and tuna has also promoted California's saltwater sport fishing industry, which brings in about $ 1.8 billion a year.
“All the sport fish from Mexico are coming up here.In fact, there are probably more sport fish up here than there are down at the tip of Baja where they usually are.Things like marlin, yellowtail, wahoo, yellow fin tuna, blue fin tuna, all sorts of things that fishermen love to catch，” said Feeney.
But southern California's warmer waters fish are forcing out other species that the local wildlife depends on.
“Fish like anchovies and sardines have moved on.And a lot of baby seals and baby sea lions are starving because the mothers can't find enough food.That might be one of the effects of El Nio，” explained Feeney.
Researchers say the northern migration (迁徙) of fish in the Pacific Ocean has been one of the most dynamic effects of the climate phenomenon.
“Historically, it's a temporary change, and once El Nio stops, the fish just go back to the cold waters.But we all know about global warming, and year by year we don't know how many of these fish will actually stick around and reproduce (繁殖)，” said Fenney.
