While there have likely been lots of new studies on age growth and life history of many of these species such as this study on grey reef sharks , as well as several new species discoveries including my favorite, the ninja Lanternshark , discovered a few years ago , my calculation includes length measurements or estimates for species of sharks that were scientifically current as of when I was in college.
By submitting above, you agree to our privacy policy. More than max out below two feet, and the smallest shark is the dwarf lanternshark at 21 centimeters, about eight inches—though the book notes that the one specimen ever seen of the pale catshark was also 21 centimeters long. Ask a Marine Biologist is a monthly column where Dr. David Shiffman answers your questions about the underwater world. Topics are chosen from reader-submitted queries as well as data from common internet searches.
David Shiffman is a marine conservation biologist specializing in the ecology and conservation of sharks. An award-winning public science educator, David has spoken to thousands of people around the world about marine biology and conservation and has bylines with the Washington Post, Scientific American, New Scientist, Gizmodo and more. They grow to an average of 15 feet in length, though specimens exceeding 20 feet and weighing up to 5, pounds have been recorded. They have slate-gray upper bodies to blend in with the rocky coastal sea floor, but they get their name from their white underbellies.
They're streamlined, torpedo-shaped swimmers with powerful tails that can propel them through the water at speeds of up to 15 miles per hour. They can even leave the water completely, breaching like whales when attacking prey from underneath. Highly adapted predators, their mouths are lined with up to serrated, triangular teeth arranged in several rows, and they have an exceptional sense of smell to detect prey.
They even have organs that can sense the tiny electromagnetic fields generated by animals. Their prey includes other sharks, crustaceans, molluscs, and sea birds.
Larger whtie sharks will also prey on sea lions, seals, and small toothed whales like orcas. The species has even been seen feeding on dead whales. Of the plus annual shark attacks worldwide, a third to a half are attributed to great white sharks. Most of these, however, are not fatal. Research finds that great whites, which are naturally curious, often "sample bite" then release their human target. It's not a terribly comforting distinction, but it does indicate that humans are not actually on the great white's menu.
Fatal attacks, experts say, are typically cases of mistaken identity: Swimmers and surfers can look a lot like their favorite prey—seals—when seen from below.
There is no reliable population data for the great white shark, but scientists agree that their number are decreasing precipitously. Overfishing and getting accidentally caught in fishing nets are their two biggest threats.
The species is classified as vulnerable —one step away from endangered—by the International Union for the Conservation of Nature. All rights reserved. Common Name: Great White Shark. Scientific Name: Carcharodon carcharias. Type: Fish. Diet: Carnivore. Group Name: School, shoal. Size: 15 feet to more than 20 feet. Weight: 2. Size relative to a bus:. Least Concern Extinct. Current Population Trend: Unknown. This photo was submitted to Your Shot, our photo community on Instagram.
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