The Blue Shark, or Prionace glauca, is a shark that is typically found in very deep, cool waters. Unless you’re diving in the depths of the ocean blue, it’s unlikely that you’ll see one; however, if you’re diving it is recommended you educate yourself on their appearances so you can steer clear, as they are considered dangerous to humans.
One of my favorite Blue shark facts is the reason behind its specially designed body. The Blue shark has a sleek, tapered body specifically made for agile, graceful movements through the water. Their tail fin moves from side to side making them extremely fast, powerful swimmers and easily able to pursue their prey for extended distances. They range anywhere from dark to light blue in coloration, and even sometimes have several shades of blue on their bodies to make a gradient, with the darkest colors on top.
On average, Blue sharks grow to about 12 to 13 feet in length, and aren’t heavy sharks at all, with the maximum weight being about 450 pounds. They have a slender body, making them easily mistaken for the pups of other shark species.
As mentioned before, one of the Blue shark facts is that the Blue shark prefers a habitat of deep, cool waters, making it an epipelagic species. It typically can be found as far down as 350 meters from the surface in more tropical waters, but will sometimes come close to shore in more temperate waters, where it can be observed by divers or people in boats. This is rare, however, and their preferred temperature to dwell in is around 50 to 70 degrees Fahrenheit.
One of the coolest Blue shark facts is that, though they are found off the coast of every continent but Antarctica, they have no set habitual area that they return to, and will swim thousands of miles to find food or for mating purposes, and can travel these distances within a very short amount of time.
Hunting And Food Sources
Due to the fact that the Blue shark will travel great distances for their food, and swim extremely quickly, Blue sharks tend to feed until they are close to bursting. Due to this, they typically will feed enthusiastically until they are forced to regurgitate their meal, only to do it all over again, making their hunger seem insatiable at times.
Blue sharks are not picky eaters by any definition of the term, and will feed on all sorts of different prey. They’re often seen feeling on schools of anchovies, and will also gladly feed on mackerel, seals, turtles, squid, and even birds! Their many rows of serrated, inward facing teeth and special gill rakers located on their gills prevent more slippery food like squid from escaping their grasp, and they will dive as deep as 1,500, if not more, in order to catch their prey.
This shark is one of the few which migrates in something akin to a “school,” or larger group of many like individuals. One cool Blue shark fact is that they also tend to show a distinct hierarchy within these schools, and are segregated by size as well as sex – or, paired in groups of all females or all males.
Blue sharks are viviparous with a yolk-sac placenta, meaning they give live birth to many pups at a time. Both females and males of this species typically reach maturity at four to six years of age, and because their mating ritual is thought to involve biting by the male, the females have adapted to develop skin much thicker than the male skin. The gestation period for pups is anywhere from 9 to 12 months, and they generally deliver anywhere from 5 to 135 pups – per litter!
Blue sharks are not without their own predators, and often the smaller individuals are a meal for larger sharks like the Great White or the Tiger shark. This species is also often the victim of several different types of parasites; for example, they easily become infected by the tetraphyllidean tapeworm by eating other hosts of the parasite.
Unfortunately, and possibly one of the most unfortunate Blue shark facts, they are also preyed upon by human fishing practices. Not only sought after for their skin – both for means of leather as well as being desired for their beauty – they are also captured and sold for cooking purposes; for example, their liver can be used for oil, and they are also sometimes caught to be eaten fresh or dried.