Tag Archives: shark nets

Ultimate Shark Facts Australia

Hammerhead

Contrary to popular belief, mainly brought about by scary shark movies, you have more chance of being killed by a coconut than a shark! Over-fishing and unsustainable practices are causing shark populations to decline worldwide. Sharks play an important role in our oceans and on our majestic reefs and we should all be concerned about their numbers declining. We believe that the big danger is not sharks; the big danger is shark extinction.

 

 Sharks of Australia

 There are considered to be around 180 species of sharks in Australian waters and 400 species worldwide. In fact, around 50 species of shark live right here, off the Eastern Coast of Queensland. Eastern Australia’s grey nurse sharks are considered critically endangered and school sharks (sometimes known as flake in fish and chip shops) and scalloped hammerheads are on the endangered shark list too.

 

Sharks Commonly Found off Australia

Great White, Port Jackson, Thresher, Zebra Shark, Tiger Shark, Tasselled Wobbegong, Whale Shark, Oceanic Whitetip, Blacktip Reef, Grey Nurse, Bull Shark, Bronze Whaler, Great Hammerhead, Blind Shark, Pygmy Shark

 

Why Do We Need Sharks?

 There is no doubt that we need sharks. As apex predators, sharks help maintain the balance of life in the sea. They are a vital part of the food chain, controlling mid-sized predators and allowing small reef fish to thrive. Small reef fish take care of our amazing coral reef, therefore sharks help keep coral reef healthy. Without sharks, we would be denied the pleasure of exploring amazing underwater habitats such as the world’s largest natural wonder, Queensland’s Great Barrier Reef. The global economic impact on tourism and of declining fish stocks would be huge. So, have no doubt, we need sharks!

 

Why Are Shark Populations in Decline?

Shark populations are in decline globally and in Australian waters. 100 million sharks are killed in worldwide fisheries each year and habitat degradation, pollution and climate change are also impacting international shark populations. Controversial shark nets and drum lines (designed to protect human populations) add further to the decline.

Sharks live a long time (20-30 years), grow slowly and take a long time to mature and reach reproductive age. This means that even if we slow the decline in shark populations now, they will take a long time to recover.

 

Sharks Facts QuizShould I Be Scared of Sharks in Australia?

No! We don’t think you should be scared of sharks. The ocean is their home and when we visit their home we need to be very aware and respectful of them.

  • On average, one person a year is killed in a shark attack in Australia.

To put things in perspective…

  • 5 people die from falling out of bed
  • 10 people are struck down by lightning
  • 1,100 are killed on our roads

 

Ultimate Shark Facts 

Check out our ultimate shark facts and discover how much you really know about sharks.

  • The largest species of shark is the whale shark
  • Baby sharks are called pups
  • Shark bones are made of cartilage
  • Many sharks have multiple rows of sharp teeth – they can grow 35, 000 in a lifetime
  • Shark skin feels like sandpaper
  • The collective noun for a shark is a Shiver (or School, Shoal)
  • The fastest shark in the ocean is the Shortfin Mako Shark (up to 74k an hour)
  • The smallest species of shark is the Dwarf Lantern Shark (smaller than a human hand)
  • Sharks have eyelids but they do not blink
  • Sharks do not see in colour
  • 10% of shark species are bioluminescent – they light up in the dark
  • 180 species of shark live off the coast of Australia – 400 species worldwide
  • Bull sharks can live in fresh and salt water
  • Some sharks lay eggs (oviparous) others give birth to live young (viviparous), and some are a combination of these two, they start life inside their mother as an egg, hatch inside her and then are born live (ovoviviparous)
  • Egg laying sharks lay egg cases known as mermaid’s purses
  • Unlike humans, sharks breathe through gills, so their nostrils are purely dedicated to smelling
  • Sharks are able to detect blood from 5 km
  • Sharks can identify which of their two nostrils have picked up a scent – enabling them to determine the direction to swim to find food
  • Some species of shark can survive for up to 3 months between meals
  • Sharks can sense vibrations from 3 kilometres away

 

What Can I Do to Help Protect Sharks?

  • Educate yourself and your friends
  • Share your love of sharks on your social media channels
  • Join a volunteer shark conservation organisation like sharkconservationorg.au, marineconservation.org.au, seashepherd.com.au (make a donation if you can)
  • Join a beach clean or just clean as you go!
  • Buy sustainable seafood and check restaurants have done so. Avoid flake at the Fish & Chip shop as it may be endangered shark
  • Ask politicians to support ocean acidification research

Ocean Life Education is passionate about protecting all marine animals and focusing on the important role sharks play in our oceans.  We aim to separate fact from fiction when it comes to the most feared fish in the sea.

Check out our Shark Discovery Program for more information on how to inspire kids to love and respect sharks: www.oceanlifeeducation.com.au/programs/holiday-program/ 

 

The High Price of Peace of Mind

We Aussies love our beaches – in the warmer months the coastline has a magnetic pull, drawing us to the sand, sea and surf in our thousands.

But while the thought of a refreshing ocean dip might be appealing, the concept of potentially coming face to face with one of our most feared predators has prompted officials to take drastic action.

Shark nets have been deployed off the shoreline of the east coast for more than 80 years.  But they offer a false sense of security.  Stretching less than 200 metres long and extending down only 6 metres, these mesh barriers are at best a deterrent and certainly don’t make beaches attack proof.

Sharks can get under, over or around them, and as it turns out, more are caught on the shore side of the net when they’re heading back out to sea, than when they’re swimming towards shore.

The holes in the mesh are around 50 centimetres across – large enough to let small animals pass through, but the perfect size for trapping bigger species.

Turtles, dolphins and rays are common victims of the nets – becoming entangled and drowning or starving to death.  A major concern is the ensnaring of humpback whales on their journey back to Antarctica after their annual breeding season in the tropics.

Calves in particular are easy prey – in just over a decade 55 have been caught in the shark nets, including one off Noosa in late September this year.  Another swam down to Sydney with the remnants of a Queensland net still wrapped around its mouth.

But the toll on the animals targeted by these barriers is far greater. In 2017 alone, more than 500 sharks were caught in the nets off Queensland – 377 died, more than 100 others had to be euthanised – only 20 were released.

Amongst the victims were grey nurse sharks which are classified as critically endangered and pose no real threat to us.  The vast majority of species share the sea quite peacefully with people – only a handful of sharks are responsible for fatal attacks on humans.

Just to put it all into perspective, on average one person a year is killed by a shark in Australia, as opposed to 5 dying from falling out of bed, 10 struck down by lightning or perhaps the most sobering, more than 1,100 taken on our roads.

Shark attacks are extremely rare and there is no scientific evidence to prove that nets protect humans.  What we do know is the attempt to keep us safe is killing marine life indiscriminately.

Removing so many animals, including apex predators, will have an impact on  local marine ecosystems – but we won’t be able to calculate that cost until far too late.

Marine biologist, Holly Richmond, feels so passionately about the need to remove all nets, she’s created a video:  www.thesharknetfilm.com

Ocean Life Education is passionate about protecting all marine animals and focusing on the important role sharks play in our oceans.  For more information about our programs including our Shark Discovery presentation visit: https://www.oceanlifeeducation.com.au/programs/

 

Shark nets, clever buoy, and protecting our beaches

Source: www.nsw.gov.au

Source: www.nsw.gov.au

Sharks, shark attacks and shark nets. You’ve probably heard the conversation in the media in recent times as our nation figures out a solution to ‘protect ourselves’ from a shark encounter.

In response to a number of shark confrontations along the NSW northern beaches (including popular spots Byron Bay and Ballina) the NSW government has carried out a comprehensive review on deterrent and detection methods to improve swimmer and surfer safety.

Ocean Life Education has long now been an advocate of education for public safety in and around our waterways. What we aim to achieve in our programs like our Shark Discovery, is a deeper understanding of sharks; the safest time and places to swim and why we sometimes come into contact with sharks.

As a long-time sceptic of the effectiveness of shark nets that are reported as protecting our popular beaches, I am delighted to see that the NSW government is reviewing both deterrent and detection methods for their northern beaches, which means that shark welfare is being considered as part of their review process.

The review mostly focuses on results of the effectiveness of such methods on the Great White, Tiger and Bull Whaler sharks and includes fourteen deterrent strategies and three detection strategies.

Review of deterrent methods

Of the deterrents, four involve electric and electromagnetic nets, ropes and cables; three are barrier nets (non-entanglement nets); five are various personal devices (worn by surfers or swimmers); a bubble curtain; and the Smart Bouy system (similar to a drum line but with capability to alert when a shark is caught so it can be quickly released).

The results showed the barrier nets were most effective, however the trials for these nets were carried out in Western Australia at a relatively protected beach where wave heights never exceeded 1.5m, therefore not a great indicator for open East Australian beaches that can have six-plus meter waves.  Not only that but keeping the barriers clean of fouling was another concern.

The electronic devices were problematic to other animals’ sensory abilities and also problematic to humans with heart problems who may use pacemakers. Personal devices varied in effectiveness but deemed not practical to protect great numbers of people at large beach sites. While the bubble curtain is an unobtrusive idea to humans and animals alike it wasn’t highly effective at deterring sharks.

Finally, there was the Smart Buoy which is just a baited drum line, with ability to alert it’s managers of a hook up, allowing the shark to be relocated. The problem here is using a baited hook brings sharks in and catches them, but also dolphins and turtles get caught too, plus staff managing relocation of animals need the right equipment and training to relocate effectively.

Review of detection methods

There were three detection methods trailed: shark spotter program; clever buoy; and tagging and real time tracking of tagged sharks.

The shark spotter program proved the most effective method of detection, the only problem is the shear expanse of coast line that needs to be monitored along the NSW north coast, which would incur a large expense.

Tagging and tracking sharks has been used by scientists for a long time now, it is effective in tracking sharks’ movements but not practical in being able to tag all sharks. Thus, this strategy rated low on the review.

Of great interest was research into technology such as the ‘Clever Buoy’, a collection of detector buoys, using sonar technology to detect large moving objects, which then sends a signal to a shore base to advise swimmers (for example a life guard tower). This detector method would keep swimmers safe and prevent the death of any marine life. It’s a win-win situation in my books.

Watch the video by Optus about how the Clever Buoy technology works.

The review did mention that this was in trial phase and needed tweaking, but with increasing technology improvements, this kind of protection for beaches is three to five years away and is both a good result for swimmers and the environment.

Final word

In 2017 we can say keep an eye on the future, it looks bright. It is great to see an improved environmental approach to an ongoing problem of humans living in harmony with the marine environment. If NSW adopts this technology and proves its effectiveness we hope that Queensland will follow suit.

Richard Coward, Director of Education

Read more