Jaws at 50: Still biting!

Strap: From blockbuster thrills to conservation chills, the great white shark still looms large—in pop culture and the ocean

Blurb:

Following the movies that made up the Jaws franchise, there was an increase in hunting and killing sharks – with a particular focus on great white sharks that were already going into a decline

 Byline: John Long & Heather L. Robinson

It’s been 50 years since Steven Spielberg’s movie Jaws first cast a terrifying shadow across our screens. At a low point during production, Spielberg worried he’d only ever be known for “a big fish story”. The film, however, did not tank.

Jaws broke box office records and became the highest-grossing movie at the time, only surpassed by the first Star Wars released two years later in 1977. A combination of mass advertising, familiar “hero” tropes and old-school showmanship launched Jaws as the first modern blockbuster. Hollywood, and our relationship to oceans and the sharks within them, would never be the same.

An unrealistic monster

In Peter Benchley’s 1974 novel that Jaws is based on, the shark is 6 metres long. For added screen excitement, in the movie it grew to a whopping 7.6 metres. However, that’s unrealistically large.

The average size of a mature great white (Carcharodon carcharias, also known as the white shark) is between 4.6 and 4.9 metres for female sharks and up to 4 metres for male sharks. The largest recorded living specimens peak at about 6 metres, with one monster specimen caught in Cuba in 1945 reaching 6.4 metres.

Earth’s oceans have seen bigger predatory sharks in the past. The biggest one of all time was the megalodon (Otodus megalodon) which lived from 23 to 3 million years ago, and may have been up to 24 metres in length. However, it looked nothing like the modern white shark. They’re not even directly related – another thing scientists learned quite recently.

Who was the megalodon, then?

White sharks first evolved between 6 and 4 million years ago in the shadows of the megalodon. A recent study showed the megalodon’s large serrated teeth show signs of it being a supreme opportunistic super-predator.

That means it ate just about anything, but especially liked whales and marine mammals. But white sharks are not directly related to the megalodon, whose lineage began with a shark called Cretalamna during the age of dinosaurs about 100 million years ago.

By contrast, the white shark lineage began with an ancient mako shark, Carcharodon hastalis. It was 7 to 8 metres long and had large, similarly shaped teeth to the modern white shark but lacking serrated edges. A fossil intermediate species, Carcharodon hubbelli shows the transition over time from weakly serrated to strongly serrated teeth.

How did Jaws affect white shark populations?

Last year, the International Shark Attack File reported 47 unprovoked shark bites to humans worldwide, resulting in seven fatalities. This was well below the previous ten-year average of 70 bites per year; your chances of getting bitten by a shark are extremely rare.

Following the movies that made up the Jaws franchise, there was an increase in hunting and killing sharks – with a particular focus on great white sharks that were already going into a decline due to overfishing, trophy hunting and lethal control programmes.

Between 80% and 90% of white sharks have disappeared globally since the middle of the 20th century. Recent estimates calculate there are probably less than 500 individual white sharks in Australian waters right now.

When Jaws first aired, scientists didn’t know how long sharks took to reproduce, or how many offspring a white shark could have each year. We now know it takes about 26 years for a male and 33 years for a female to sexually mature before they can start having pups.

Data about white shark births is sparse, but recently a 5.6-metre-long female caught on a drum line off the coast of Queensland had just four large pups inside her. This is a very small number. Some large sharks, such as the whale shark, can give birth to up to 300 young.

Now that we know just how slow they are to breed, it’s clear it will take many decades to reestablish the “pre-Jaws” population of white sharks – important apex predators in the marine ecosystem.

Will white sharks survive?

White sharks are currently listed as vulnerable. This classification means if we don’t change the current living conditions for white sharks, including impacts caused by human activities such as commercial fishing, and the impacts of climate change and ocean pollution, they will continue to decline and eventually could go extinct.

Currently, white sharks are protected in several countries and form the basis for an important tourist industry in Australia, South Africa, western United States and most recently Nova Scotia, Canada.

These sharks are iconic apex predators that fascinate people. In terms of economic impact, they are worth far more alive than dead.