Be careful what you wish for seems appropriate in this story about the protected—due to a 1972 law—sea lions eating the protected salmon at the confluence of the Sacramento and American Rivers.
The well intended wishing to protect the sea lions may be contributing to the decline in salmon fishing, at least for the human fishers; sea lions are doing just fine. :)
An excerpt.
“Ask a Sacramento angler for reasons why Central Valley salmon populations have crashed over the past two years, and this is likely to be high on the list:
"Dozens of sea lions that live between Rio Vista and Verona year-round," said Sacramento fisherman Terry Horst. "That's a major problem because they eat tons of fish a day."
“Scientific brain power has been applied in thick doses to many aspects of the alarming fish declines in the Sacramento-San Joaquin Delta – from weather patterns to water pollution. No one with a science degree, however, has had anything to say about sea lions.
“Now Mark Dendy, a professor of biology and natural resources at American River College, has produced a survey of the Delta sea lion population. And, yes, there are resident sea lions, though not nearly as many as fishermen think.
“According to Dendy, five individual California sea lions live most of the year in the Sacramento River. They account for most sightings between Isleton and Colusa.
“These five spend much of their time in the river near downtown Sacramento, at the confluence with the American River. Dendy has seen them eating catfish and striped bass. But their favorite appears to be chinook salmon – as many as one every 45 minutes...
“Since 1972, the Marine Mammal Protection Act has made killing and harassing sea lions a crime. The law followed steep population declines caused by hunting for fur and blubber, and it was a success.
“The population of California sea lions is not endangered and now could be as high as 300,000, with an annual growth rate near 6 percent, according to 2007 federal data.”