The numbers of scalloped hammerhead and tiger sharks appear to have declined by more than 97 percent from 1970 to 2005, while populations of bull, dusky and smooth hammerhead sharks could be down as much as 99 percent, according to this analysis.

• 根据这份报告的分析，一九七0年至二00五年间，双髻鲨和虎鲨的数量减少了超过百分之九十七；公牛鲨、黑鲨、平双髻鲨的数量甚至减少了百分之九十九。