SA White Shark Numbers Plummet

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SA White Shark Numbers Plummet

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SA White Shark Numbers Plummet

BY MELISSA REITZ - 30 AUGUST 2016 - SA BREAKING NEWS

Recent results of a population count of Great White sharks around the South African coast have shown that the survival of the species is in a critical situation, reigniting the debate around cage diving and the role it plays in shark conservation.

A study led by Sara Andreotti of Stellenbosch University has found that the protection afforded to Great Whites in South Africa over the past 15 years is failing. Only about 500 remain along the coastline – half the number counted by the KwaZulu-Natal Sharks Board in 1996.

The study, which used photo identification and genetic testing, also found that with a mere 300 breeding adults left, the lack of genetic diversity has become a significant concern and may lead to extinction of this elusive apex predator.

In response to these alarming figures the Endangered Wildlife Trust (EWT) has issued a statement calling for a review of the baited shark diving industry of which there are 12 independent companies operating between False Bay and Mossel Bay.

“Although the (shark diving) industry claims to support and expand shark conservation efforts, it is often not clear how these are actually benefitting the various shark species in South African waters,” says the statement. They go on to say that until policies and regulations have been revised a ‘precautionary approach’ is needed.

EWT says the shark diving industry uses ‘sensationalism’ and ‘fear mongering’ to promote dives rather than promoting education and conservation of sharks.

Shark experts and cage diving operators have rejected the claim, saying the EWT is basing its statement on misinformation and outdated research.

“It is short sighted to throw a blanket of disapproval over this industry,” says Chris Fallows of Apex Adventures. “Cage diving is the main reason there are still white sharks in South African waters. It is we who have informed the government of poaching, illegal operators or poorly conducted research on sharks. We have provided funding for many of the most comprehensive research projects that have taken place.”

Kim MacLean, chairperson of the Great White Shark Protection Foundation, and founder of the shark diving industry in Gansbaai, disputes the EWT’s claim that it does not educate: “Clients arrive at briefings in fear and the JAWS music echoing through their minds. But on their return it’s quite clear that they have seen the animal in a completely new and realistic way. This is education at its best.”

According to the EWT, sharks’ natural behaviour is altered when chum or bait is used to attract them to boats.

“One of the key conservation issues is the frequent conditioning of wild animals to divert them from their natural behaviour to engage directly with humans in response to stimulation,” says the EWT statement.

But a recent scientific paper on the impacts shark diving tourism has on sharks says there is still insufficient evidence to prove that baiting, or provisioning, has long term effects on shark behaviour, and it needs to be noted that individual sharks react independently to stimuli.

A report on the effects baiting has on Great Whites done by South African scientists, including Alison Kock of Shark Spotters in Cape Town says: “Although ecotourism activity had an effect on the behaviour of some sharks, this was relatively minor, and the majority of sharks showed little interest in the food rewards on offer.”

Operators agree that more active monitoring by the Department of Environmental Affairs is needed to strengthen compliance. But they also claim the majority of operators work within a strict code of conduct, including the limit of 5kg of chum a day.

“Most operators abide by terms and conditions,” says Alison Towner of the Dyer Island Conservation Trust in Gansbaai. “It’s looked down upon to lose bait or mishandle a white shark. Boats often lie close together and will report an unethical practice.”

Meanwhile as the debate continues in the Western Cape, the conservation of sharks is facing a far greater challenge in Kwazulu Natal. Nets and baited hooks, which line a large portion of KZN’s coastline, have been deployed to protect swimmers from sharks but are not protecting sharks from humans. Each year these devices kill more than 500 sharks, of which, at last count, included 26 Great Whites.

Although alternatives such as electromagnetic deterrents have been considered, the KZN Sharks Board says they have yet to find a viable solution that suits their extensive coastline.

Perhaps the time has come to review the use of shark deterrents and the impacts they are having on Great Whites?

Original article: http://www.sabreakingnews.co.za/2016/08 ... s-plummet/


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Re: SA White Shark Numbers Plummet

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:ty:


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Re: SA White Shark Numbers Plummet

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Maybe it is time that if you go swimming you'll have to consider the sharks :yes:


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Re: SA White Shark Numbers Plummet

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Blimey... is there ever good news about any kind of species these day O/


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Re: SA White Shark Numbers Plummet

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Very rarely :evil:


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Re: SA White Shark Numbers Plummet

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Where are the Great Whites? Bronzies and cow sharks taking over False Bay

2018-10-04 12:00 - Gabi Zietsman

Something fishy is happening in False Bay.

Last summer, Cape Town-based, non-profit safety and research organisation Shark Spotters recorded a new low for great white sightings along the beaches of Cape Town, reports Save our Oceans Foundation. At the same time, however, the number of bronze whaler sharks, or bronzies, have increased in False Bay and sevengill cow sharks have taken over Seal Island, and now 'cow shark cage diving' has become the new push from tour operators in the area.

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Great White shark forces halt to South African surfing event
Surfers scramble out of the water as a Great White shark starts taking an interest.

How did it use to be?

Great white sharks used to be the top of the food chain in the area (before orcas moved in) and could hunt without competition from other predators. In winter they gathered around Seal Island to hunt the inexperienced pups, but when their prey has learned the knack for not getting eaten by the summer months, the great whites move inshore to feast on shoals of fish and getting a little too close for comfort to human swimmers.

Cow sharks and bronzies tended to avoid these alphas and the former stuck to shelter during the day and hunted at night, while the latter only used to venture in small numbers to False Bay during summer.


What has changed?

This however has changed over the last year.

"If you have a look at Figure 1 below, you will notice that the last six years have yielded a downward trend in the number of white sharks recorded by Shark Spotters in the inshore zone of False Bay. This trend has also been observed at Seal Island, where the famous 'Flying sharks' of False Bay have been increasingly scarce, leaving their worldwide fan base disappointed for multiple seasons," writes Tamlyn Engelbrecht from Save our Oceans.

There have been dips in the white shark populations before, followed by a surge afterwards, but today that dip has been going on for much longer than usual, with a surge in bronze whaler sightings, says Save our Ocean.

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Number of shark sightings per day of spotting effort across all Shark Spotters beaches in Cape Town over the period from 2007 - 2018. (Graph: Tamlyn Engelbrecht, Save our Oceans)

With the top predators gone, cow sharks have taken over the Seal Island territory, and the bronzies are more prevalent in the inshore zones. This has resulted in shark cage diving operators in the area starting to advertise 'cow shark cage diving' instead of the now more scarce great whites, which has become more a bonus sighting rather than a guaranteed one.

Why is this happening?

Save our Oceans note that the reason for the decrease is still up for debate. Some believe the cause of the decline could be attributed to the May 2017 attack of three great white sharks by orcas, their carcasses washing up on the shore.

The Department of Environmental Affairs has labelled the decline a natural phenomenon - due to a change in temperatures and the food chain of the animal kingdom. The Atlantic Ocean waters are being affected all across the globe and the reasons remain unclear.

Gansbaai is also feeling the decline. According to the Marine Dynamics blog post on 5 October 2017 - great white sightings in Gansbaai have dramatically decreased but there is still hope that this will improve.

Save our Oceans however see that "the observed decrease in white shark presence in False Bay does not appear to be mirrored all along the South African coast, with certain areas on the south and east coast actually experiencing increased white shark activity lately. This is promising as it points to a regional distribution shift, rather than a country-wide population decline, which would have far worse repercussions for our coastal ecosystems."

What does the future hold?

But what does this mean for the future of sharks in False Bay and the tourism dependant on them? Save our Oceans just doesn't know enough to say for sure, but research is being conducted to get a better understanding of the decline and behaviour of the different shark species. Tagging is being done when possible around Seal Island, and they are looking to get hold of a bronzie to tag so they can learn more about their elusive nature.

Shark Spotters have also started a volunteer programme, where you can get involved with the organisation and help them continue their research through fundraising, logistical and awareness raising support.

"It is hoped that through ongoing research, environmental monitoring and collaboration with other researchers, we can gain a better understanding of what is driving these current changes, and what the future holds for the sharks of False Bay."

As we approach summer though, beachgoers still need to be on the lookout and make careful note of the shark flags that are installed across Cape Town's beaches - great whites can return when you least expect it.

WATCH: Spectacular slow motion footage of great white sharks in Gansbaai

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"Education is the most powerful weapon which you can use to change the world." Nelson Mandela
The desire for equality must never exceed the demands of knowledge
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