For years, environmentalists have been worried about the overfishing of white marlin. However, studies have shown white marlin populations to be low, but not perilously so. A recent petition to put the white marlin on the endangered species list was even turned down. It turns out that a significant portion of the "population" of white marlin is not white marlin at all, but a newly identified species called a roundscale spearfish, which bears a stunningly close resemblance to their whiter, more marliny brethren.
These elderly gentlemen might not be so smiley if they knew that they were contributing to the destruction of a species. Who am I kidding, all three of them are drunk.The truth is that only a highly trained eye or a geneticist can tell the difference between the two species. Unfortunately for the fish, most commercial and recreational white marlin fisherman have neither the desire to calculate the ratio of the distance of the animal's urogential opening from the anal fin to the height of that fin nor access to a state-of-the-art crime lab.
White marlin--seen here in full "attack mode"-- subsist on a diet of mostly seagull. 
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