One of the most well-known but demonized animal species in the world, the Great White captures our attention as an ancient and powerful predator.
DID YOU KNOW:
White sharks are endothermic, or warm-blooded, allowing them to maintain a higher body temperature than the surrounding waters which enables them to move more quickly in colder waters.
FAMILY: Lamnidae (mackerel sharks)
SCIENTIFIC NAME: Carcharodon carcharias
COMMON NAME: White shark, White pointer
The genus name Carcharodon is derived from the Greek “karcharos” = sharpen and “odous” = teeth. The species name carcharias, also translated from Greek, means point leading to its common name in Australia the “white pointer”.
TYPE: Fish
IUCN Red List Status: Vulnerable (assessed 2018)
SIZE:
Being the largest predatory fish in the world, white sharks can reach lengths upward of 20 feet (6m) and weigh several tons with the largest individuals recorded being female.
AVERAGE LIFE SPAN:
Scientists estimate white sharks may live 70 years.
White sharks reproduce via viviparous and oophagous reproduction- meaning embryos hatch in the uteri and are nourished through ingestion of unfertilized eggs until the female gives live birth to small numbers of young (2-17 pups).
Gestation time is still unknown but believed to be around a year or more with females giving birth every two or three years. Pup size at birth is between 3.5-5ft (109-165cm) in length. Male sharks mature at around 10-13ft (350- 410cm) and females at around 14-16ft (450- 500cm).
DID YOU KNOW:
White Sharks have been documented through anecdotal records since the Middle Ages.
DISTRIBUTION:
Known to be highly migratory, with individuals making long migrations every year, white sharks predominantly occur in temperate seas. Great Whites commonly patrol coastal archipelagos inhabited by common prey items like seals, sea lions and walruses. They are also found around offshore reefs, banks and shoals or rocky headlands where deepwater drop offs come close to the shore.
Being a pelagic species, they range from the surfline to the open ocean and from depths of over 1300m (4265 ft), spending little time at midwater depths.While white sharks venture into cold, boreal waters they spend much of their time in the upper part of the water column in nearshore waters.
DIET:
White sharks are macropredators which prey on larger marine mammals including: seals, sea lions, dolphins, elephant seals, scavenged whale carcass, etc. In fact, white sharks play a crucial role in marine ecosystems by helping control pinniped (seals and sea lion) populations that could otherwise go unchecked.
Interestingly, only mature white sharks prefer the larger marine mammals while juvenile sharks typically prey on fishes, marine reptiles (mainly sea turtles), seabirds, other small shark species and rays.
Both adult and juvenile great whites are ambush predators that are active during the daytime. White sharks have also been recorded taking deep dives, presumably to feed on slow-moving fishes or squid in deeper, colder waters.
Although most fishes are cold blooded, great whites have a specialized blood vessel structure called a countercurrent exchanger- this special adaptation provides white sharks a major advantage when hunting in cold water, particularly in hunting warm-blooded marine mammals that may otherwise have too much energy to be successfully captured.
DID YOU KNOW:
Great Whites have few predators, however Killer whales (Orcinus orca) and larger sharks can pose a real threat to an adult White shark. It's suggested that Orcas may target white sharks for their fat rich livers.
CONSERVATION:
"Although white sharks are often in the news and are characterized as the most common villains in films like 'Jaws' and programs like Shark Week, white sharks remain one of the least understood of the sea’s creatures."
According to the International Shark Attack File (ISAF) white shark has been credited with more fatal attacks on humans than any other species of shark due primarily to its size, power and feeding behaviors.
WATCH NOW:
White Sharks are frequently caught by humans- they're caught as bycatch mostly in inshore fisheries in a range of gears, such as longlines, setlines, gillnets, trawls, hand-held rod and reel, and fish-traps. These sharks are also targeted in beach protection programs in Australia and South Africa that deploy drum-lines and gillnets. Specimens are reported every year in gill nets, trammel nets, herring weirs, purse seines, tuna enclosures as well as on surface hooks, bottom longlines and set-lines.
Great whites are also targeted due, in part, to increasing monetary value placed on their jaws and teeth by trophy collectors for use in public/private display in buildings or even homes. Shark flesh is often used for human and animal consumption, their skin for leather products, their liver for oil in healthcare supplements, their carcasses for fishmeal found in pet foods and more well known- their fins for shark-fin soup.
These threats are extremely worrisome to researchers of the already vulnerable, still mysterious lifestyle of Great White populations. The fact that most shark species are slow-growing, produce few young and face continual pressure from overfishing, climate change and a 'bad reputation' that lingers from pop culture and the media compiles to make their future and very survival uncertain.
How to help:
Depending on where you live, there are always more, indirect ways to help save sharks. Beach clean ups, educating yourself and friends and being aware of policies and regulations in your area is HUGE! Know your local and federal representatives that can help create more protected areas and more regulation for trade and environmental justice initiatives (VOTE!).
Another way to help sharks is to call out misinformation or fear-mongering however you can.
Don't buy a ticket or otherwise participate in wildlife 'shows' or dive operations that put sharks or their ocean ecosystem at risk.
Call out shows/the media, celebrities, even your friends or family when you hear fallacies regarding sharks.
Let's be done with the days of 'man-eater' or 'demon' in news headlines, shark attack imagery plastered on t-shirts or in ads seen while scrolling our social feeds. It's time to educate yourself and help turn the tide for these vital oceanic animals once and for all.
You can also support organizations that are working to protect and study these sharks: OCEARCH, Atlantic White Shark Conservancy; also check out these cool tracker apps SHARKTIVITY from AWSC and follow along with @OCEARCH for updates on tagged number of Great Whites in real time.
Check out more in-depth information about
this species with below source links and shark organizations!
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