North Island Tagging

January 31, 2015

January 17th and 18th and 25th we were fortunate to be invited to assist tagging white sharks once more for the continued study and research of their fine scale movements around the North Island. The three days were spent around the Kaipara Harbour, an area long known to be popular for encountering pointers.

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From left: Bruce Goorney (WSCT), Clinton Duffy, David Romeril, Scott Tindale (skipper)

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Red October sporting a WSCT logo!

We have joined expeditions on the Kaipara in past years, but apart from the occasional ‘hook-up’, success has been minimal. This has been made all the more frustrating with numerous reports being made (at times, weekly) from recreational fishermen encountering white sharks, and commercial fishermen finding them tearing through their nets in the harbour.

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Even it seems Auckland City Council have had more success in seeing them than us!

We have always known they are there – but they have always remained elusive to us… Till now!

Saturday 17th of Jan was the turning point and that, it has to be said, is an understatement with seven ‘hook-ups’ and an eighth shark estimated at 3.4 meters found swimming around our anchor buoy’s on return from the second successful tag deployment. The sharks ranged from approximately 2 meters total length (TL) to 3.5 meters. Two smaller juvenile sharks, a 2.1 m TL female named Caitlin, and a 2.2 m TL male named Thomas D were tagged along with a third female named Sue, estimated at 3.5m TL. Four tags were deployed in total.  A SPLASH and a PAT tag on Thomas D, a SPOT tag on Catlin. and a PAT tag on Sue.

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SPOT tag on Thomas D (2.1 m TL male) Dorsal Fin

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PAT tag on Sue (3.4 m TL Female)

Both the SPLASH and SPOT tags started to generate data within 48 hours of deployment as can be seen on the ARGOS map images below.

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Thomas D’s movements over the first 72 hours

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Caitlin’s movents ov the first 72 hours

The rigs being used all had re-curved barbless hooks which contributed to the low numbers successfully brought to the boat and tagged. Barbless re-curved hooks were used to ensure deep hooking could not occur and the hook could be easily extracted .

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One of the hooks used that was spat out before the shark could be tagged.

The draw-back to this rig is if tension is lost on the line the hook will usually fall out of the animal’s mouth, however this does mean if the shark bites through the leader or trace the hook will fall out causing minimal injury.

Sunday 18th of Jan was less successful with only three ‘hook-ups’ and no successful tag deployment, however in comparison to past years on the Kaipara, even this was considered a success in its own right.  The following Sunday 25th we headed out again, but sadly on this day we struck out without a single hook up, however, data obtained since that first weekend showed us that Caitlin,  the 2.1 m female had headed north and is about 10 km off Ninety Mile Beach on a nw heading. Since we tagged her she has travelled about 452 km, giving a rate of movement/ displacement of about 41 km per day.

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Thomas D, the 2.2 m male is still going around in circles about 22 km off Manukau Harbour!

News has travelled fast and on Jan 31st the Herald published a short article about the expedition.  You can read the article here!.

A look back at 2014 for the White Shark Conservation Trust

January 2, 2015

2014 was our quietest year since we started in 2009 from all angles.

Our Facebook presence was largely dominated by the events in Western Australia which we have been following now for a number of years. This year marked the trail of a cull order by their premier, Collin Barnett. An order advised against by shark scientists in Australia and around the world.

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Photo credit: Perthnow.com

By the time the trail had ceased well over 100 sharks had been taken on the set drum lines, but not one of the target species  (white sharks), had been caught.  The cull order was met with protest and disgust by Western Australians and through social media, the rest of the world.  (An anti cull rally was organised by Shark Aid International in the UK outside the Australian Embassy in London in protest).  The cull order was lifted in September and in October a surfer survived an incident which resulted in two pointers being caught and destroyed.  In November a dead whale was filmed off Perth with a number of sharks including at least one white shark swimming around it whilst a local was filmed climbing onto the floating carcass (not the brightest of moves we must say).

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Photo credit: Perth Now

In December a pointer was seen close to beaches off southern WA, and again the WA Fisheries department deployed drum lines to attempt to kill the shark.  This particular shark had been tagged in 2013 by the WA Fisheries department and their actions sparked worldwide protest again.  Thankfully the shark left the area without incident and the drum lines were removed.  Finally, sadly at the end of December a young spear-fisherman was attacked and killed by what was reported to be a white shark at Cheynes Beach WA triggering another hunt for the shark by the WA Fisheries dept.

 

More relevantly, we have had a number of reported sightings around our coast throughout the year and one incident in February at Porpoise Bay, in the Catlins area of eastern Southland coast when a surfer was bitten on the leg by a juvenile pointer.  The 28-year-old UK immigrant apparently punched the shark on the nose and swam to shore.

In March, NIWA and Department of Conservation returned to Stewart Island for the last time to tag and track white sharks that aggregate there, marking the end of a 10 year research project.

Photo credit, Clinton Duffy 2014

Photo credit, Clinton Duffy 2014

Three juvenile white sharks were followed during 2014, Pip, a 3.3m female shark; Caro, a 3.7m female; and Nicholas Cage, a 3.5m male shark. Pip was tracked across to New South Wales near Sydney, and data showed she took 20 days to travel 2020km from the southern Snares Shelf. She continued  northwards to Queensland waters.  Caro remained around Stewart Island for several months before starting begin her northward migration.  Nicholas Cage was tracked north as far as New Caledonia before turning round to return to our west coast.

Image Credit: NIWA

Image Credit: NIWA

The 10 year study showed that the sharks travel in a remarkably straight line on their migrations, averaging about 5km/h or 100 km/day, but have done up to 150km a day.  Data indicated they tend to spend time at the surface but also make regular dives between 200 and 800m – the record depth is 1246m.  For further information click here.

 In August we were fortunate enough to be invited to attend a necropsy of a juvenile white shark that was accidentally caught in a commercial set net off New Plymouth.  10626542_966289726730626_8634576691192716040_nThe fishermen concerned found the shark dead and contacted Department of Conservation who donated the shark to the museum. The shark was a 2.6TL juvenile male weighing 140kg. Parasites were collected both externally and internally for examination. The shark’s head was removed and has been preserved in order to CT and MRI scan it for research.

September we were invited to present a seminar to the Auckland Zoological Society.  Our seminar was based on the changes in public perception toward the White Shark over the last 50 years and looked at how the white shark was initially portrayed by Blue Water, White Death (the first white shark documentary), and Jaws in the 1970’s and compared this to the documentaries and attitudes of today.

In December a small group of experts and cinematographers set off to attempt to tag and track white sharks migrating north from the Three Kings area.  Among the team was Clinton Duffey, Andy Brandy Casagrande and Kina Scollay (not in image).IMG_4122Unfortunately the expedition was hampered by bad weather and was unsuccessful.

Finally, just after Christmas a family out fishing for snapper in Auckland’s Waitemata Harbour got a big surprise when their bait was taken by a white shark which breached not far from their boat and was estimated to be between 4 and 4.5 meters!  The shark continued further in to the harbour, reportedly passed Point Chevalier travelling towards the Rosebank peninsular (where our head office is located!!!).

Here is to a busy 2015!

 

2014 New Zealand Zoological Society Seminar

August 10, 2014

2014 New Zealand Zoological Society SeminarClick here for more information

Permits to be Required for Cage Diving Operations

March 2, 2014

Recent events in Stewart Island have resulted in the Minister of Conservation, Nick Smith, announcing this week that as of the final quarter of 2014, all commercial white shark cage diving operations in New Zealand will require have a permit under the Wildlife Act 1953. The timing of this requirement ties in with the start of the 2014/2015 summer season.

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Until now government has been reluctant to implement permits for cage diving operations as it was believed such regulations would have a negative effect on the industry, however conflicts between Stewart Islanders and cage diving operators has highlighted the need for the growing industry to be properly managed. Commercial paua diving is an important industry on Stewart Island. New Zealand law dictates their work must be done without the aid of compressed air and they must free dive for their bounty. Many are convinced the cage diving operations attract sharks into the area and modify their behaviour.  Their main concern is that the presence of divers in the cages and the use of berley to attract them,  may condition the sharks to think of divers as food.  The cage diving operators argue that this is not the case and point out that local fishing boats actually discharge far more berley than their operations.

In South Africa, white shark cage diving has been in existence for many years with multiple operators.  The question of behavioural modification has understandably also been a topic of discussion there, and although several studies have been on the subject there has actually been little long-term research into this.  Kiwi born shark scientist, Ryan Johnson and Alison Kock published research work in 2006 (South Africa’s White Shark cage-diving industry -is their cause for concern?) conducted in South Africa which looked directly at this issue.  They concluded that, “Conditioning can only arise if white sharks gain significant and predictable food contravene current permit regulations prohibiting intentional feeding of sharks. On rare occasions, indications of positive conditioning have been observed at Mossel Bay (four sharks).  Evidence exists that adherence to permit regulations and infrequent or no feeding of sharks does not promote conditioning, and may in fact cause sharks to temporally ignore chumming vessels rewards.  Thus, conditioning will only arise if operators intentionally and willfully”.   One observation that is made time and time again by cage diving operators (and their customers) worldwide is that in visiting the same dive zones regularly, there is never a guarantee that a white shark will even show up.  It may take a few minutes, or a few hours or none arrive at all.  This fact alone must in some way indicate that ‘conditioning’ to associate cage operators and humans with food is questionable so long as the cage operators do not intentionally feed the sharks or use excessive berley to attract them.

In July 2013 the Department of Conservation published interim guidelines for operators of commercial white shark cage diving operations.  The guidelines were issued to ensure cage dive operators conducted their operation in a manner that ensured the wellbeing of the sharks. The interim guidelines identified some activities associated with cage diving that pose a risk to great white sharks.  Within Appendix B of the guidelines, a table of possible risks in the operation touches on the subject on possible conditioning with respect to throw baits and states only one throw bait should be used at a time and all efforts should be made to not allow the shark to take a throw bait.

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The Department of Conservation had originally intended the interim guidelines to be reviewed and feedback given by operators in 2015, however, the recent visit to Stewart Island by Nick Smith has changed this and permits will now be required by the end of 2014.

References:

Commercial Great White Shark Cage Diving New Zealand.  July 2013.  Department of Conservation Interim Guidelines

South Africa’s White Shark cage-diving industry -is their cause for concern? Johnson, R. and Kock, A. 2006

The effects of shark cage-diving operations on the behaviour and movements of white sharks, Carcharodon carcharias, at the Neptune Islands, South Australia. Bruce, B.D., and Bradford, R.W. ; 2012

Effects of a cage-diving operation on the fine scale movement of white sharks (Carcharodon carcharias).  Huveneers, C. , Rodgers, P.J., Beckmann, C., Semmens, J., Bruce, B.D. and Seuront, L. 2012

For further information about cage diving and possible behavioural conditioning please refer to the above links.

Tragic Incident at Muriwai

February 27, 2013

We are deeply saddened at the news of the shark incident at Muriwai earlier today that took the life of a swimmer. Our deepest condolences go out to the family and friends.
Exact details of the incident remain unclear, but we hope this will change as the investigation continues. From what we know the incident occurred about 200 meters from shore and involved a single shark estimated to be around 12 feet in length, and a long distance swimmer. The shark species remains unidentified at this time. We understand police were quickly on the scene in a launch to recover the swimmer’s body. It is unclear whether the shark is still in the vicinity and the beach will remain closed for a few days while aerial searches are done.
This tragic event is a very rare occurrence in our waters, even though we know sharks to be present all year round.

2013/14 Entertainment books – Buy yours from us

February 20, 2013
Entertainment Book

Entertainment Book

We are pleased to announce we will be selling the Auckland entertainment books for 2013/2014. We are taking pre-orders NOW!!! E-mail us to pre-order your copy at whitesharkconservationtrust@gmail.com.

There are loads of vouchers for restaurants, movies, activities, accommodation and the White Shark Conservation Trust gets a share of the sale price for everybook sold. It’s easy to get your money back and can save hundreds of $$$$ ( you only have to use ot Entertainment book a few times and it will have paid for itself!!!!) – and of course every book sold helps in supporting New Zealand white shark conservation and research. Each book is only $65 (NZD) each – they are great value and make excellent gifts!

Get your book pre-ordered today and look forward to a year of savings!


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