On today’s Species Tuesday, we bring you the Great White Shark (Carcharodon carcharias). Technically just called the white shark (the term “Great” was added by popular culture later), this species can reach about 4-5 meters in length and weigh 1,500-2,400 pounds. Unfortunately not a whole lot is known about their life cycle, though it’s estimated that they can live up to 70 years in the wild. The white shark sports a very fashionable gray and white coloration. The dorsal area of the shark (typically closer to the surface) is a dark gray, while the ventral area (closer to the ocean floor) is a light gray. This mottled appearance allows the shark to blend in to its environment when viewed from the side, a view that many unfortunate fish and marine mammals experience before they head to the Great Ocean in the Sky.
White sharks have a very keen sense of smell, and are able to detect muscular electrical impulses in the water (like many other sharks) that help them find moving prey. However, they don’t have great vision. It’s thought that the majority of white shark attacks on humans occur in areas of high sensory impairment, essentially where the shark gets disoriented and can’t tell what’s what. Sharks do not, in fact, mistake humans for seals; they are rather curious as to what we are and can tell after a single bite that we’re too bony for their liking.
It’s thought that there are at least five major populations of white sharks throughout our oceans: the Atlantic North American population, the Pacific North American population, the New Zealand population, the Australia population, and the South African population. While some researchers believe that the South African and New Zealand populations exhibit some mixing, not enough is known about these distinct populations to determine whether they are genetically isolated or not.
White sharks are listed by the IUCN as vulnerable to extinction. Though their populations have been on the rise over the past few years, they still face many threats to their lives and their natural habitat. White sharks are unfairly labeled as killing machines, and this culture of fear that surrounds them has caused significant population declines over the past three or four decades. White sharks are frequently killed as bycatch by fishing vessels, and are unfortunate victims of the shark fin trade in the eastern Pacific. However, recent conservation efforts have been established in various countries to
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