New research finds swimmers and surfers today are about 90 percent less likely to be attacked by sharks off California than they were in the 1950s — even though there are hundreds of thousands more people in the water.

The findings mark a stark contrast to recent headlines in North Carolina, where shark attacks this year have reached a record high.

Stanford researcher Francesco Ferretti says more study is needed to account for the apparent disparity.

Ferretti says although the reported number of attacks off California has risen slightly, the risk of attack there has plummeted over the past six decades. The decline likely is the result of surging populations of sharks' prey, such as sea lions and elephant seals.

Researchers say there might also be fewer sharks in the water, though their populations are hard to track.