July 2012 Shark Bytes
Posted on Tuesday, 31 July 2012
Dear Shark Lovers
Finally the panic is over and the Great White Sharks are back at Seal Island going about their normal behaviour as they should be doing every winter! What a relief and we have been so excited to have great days with them again…The month still started out a little slowly but it has been building with good numbers of sharks around the boat and as of the last 2 weeks the intense hunting behaviour on cape fur seals has really started to pick up. Watch below for a couple of very interesting events we saw this month …
Old Shark Friends Return to Seal Island
One of the most surprising and rewarding aspects of working with Great White Sharks is getting to know individual animals and their unique personalities and character. The Great White Shark is an extremely rare animal and this is clearly displayed when we see the same sharks returning to Seal Island each winter, year after year. With the estimated worldwide population suggested being 2,500 to 3,000 animals it make the life of each shark very important.
Each year during our off season we spare a thought for the perils that the sharks face in our ocean today, and as you can imagine the relief and excitement when we see our regular sharks return back to Seal Island each winter is very real.
This past month we had 2 of our very favourite sharks sighted at Seal Island. Although they are both males around the same size, the 2 sharks could not be more different in character. This is also the 10th season for both of them at Seal Island that we are aware of.
Cuz is now very close to 4 meters and not only is he a very good hunter he is also very interactive and relaxed around the boat.
We first saw him in 2003 when he was just less than 3 meters in length. He was crazy around the boat, always looking at the bait and the decoy, and constantly putting his head out of the water. He is also very comfortable with the boat and has no problem coming very close. Everyone that sees him loves him! His behaviour is very similar to that of the famous “Rasta”, an incredibly relaxed and lovable female shark. Since he was so similar in behaviour to Rasta, Cuz, seemed a very fitting name.
We have seen Cuz most days at the boat over this past month, and each time he gave everyone a great show. One of my favourite things to do with him is to get really low to the water by leaning over the dive step, that takes me to water level and Cuz very often will pass close by very slowly. He is very curious and whenever I do this I can see him looking at me. It’s not so often that you can see the pupil of a great white’s eye, most people have the impression that it is just a dark orb. Not so, if you can get a close look there is a very clear and darker pupil, Cuz makes its easy to see his.
He has not grown a great deal since last year but he still looks in good shape, although he is sporting new bite mark scar (from another shark) down his right flank. I guess now that he is getting older he is also obtaining character scars.
Shy Guy is also around 4 meters in length and has a badly damaged Tail Fin which is very easy to identify. Every time he successfully hunts a seal and feeds on the surface, the tail fin gives us a clue as to who he is. This past month we observed him make 2 successful kills at Seal Island, our first sightings of him during the 2012 shark season. Shy Guy has the exact opposite personality of Cuz. The amazing thing is, in the past 10 years he has only ever come up to the boat once. So, we know he is present at Seal Island at certain times but he is one those sharks that just has no interest in the boat or is perhaps wary of the boat. So, maybe he chooses not to risk something that makes him uncomfortable.
I particularly love sharing the history of this shark as most people assume if there is bait in the water, a great white will automatically come and have a look, that certainly is not so with Shy Guy !
Overall the numbers of sharks around the boat have been great, averaging 6-8 sharks per trip. They have been interactive so the shark cage diving has been great with everyone getting great views underwater. There have been a number of smaller sharks that have been at the Island most of the month so it has also been great to see these guys on a regular basis. Interestingly these 5/6 sharks are all a similar size, just under and just over 3 meters in length.
There has also been a very big shark hunting at the Island which we presume is female and we have seen her on a number of predatory events. She has come up to the boat just once but it enabled us to get a closer look at her. We sized her at 4.3 meters which is huge and she has a very impressive girth. We also noted the parasites, copepods, on the top of her head so we may be able to identify her again over the season …
July is normally our high predation activity month and most days from around the middle of the month we have seen high numbers with at least 10 events each day, made up of both successful events for the sharks, as well as misses. There have been 2 very high days with 26 and 21 events. Both days were completely different with regards to weather. One was stormy, windy and wet and the other was perfectly flat calm … On the calm day we twice had 2 events taking place at the same time and only 80 to 100 meters apart. In this kind of situation your heart is beating at a million miles an hour and it’s tough to decide which one to focus on. Seal Island is indeed an incredible place!
There have also been a number of highly unusual and first time experiences for me …
An Unusual View of a Predation at Seal Island
We have to be very sensitive when working around these events so that we impact as little as possible on each event. This means we have to be very aware of seal movement so that we do not block their path or cause them to try use our boat as protection. It takes a lot of caution and vigilance to make sure all of this happens. Unfortunately on rare occasions we do get things wrong.
One morning this month we did not see an approaching group of seals while we were towing our fake-seal decoy and the seals headed straight for the safety of our boat. Once we realised what had happened we stopped our tow so that we could wait for them to move off.
As they did so, a patrolling Great white shark picked up on them a mere 3 meters from the boat.
I was on the top viewing deck at the time so I had a very spectacular view of the whole event looking straight down into the water.
The seals did a duck and a dive that we know is a reaction to an approaching shark. As I looked down I saw the white flash of a shark’s pure white underbelly as it propelled itself towards the surface. The shark was not in line with the seal so it had to deliberately change its course underwater and so flung itself sideways towards the fleeing seals.
It then did a sudden deep bank with intense speed and then propelled itself upwards again in hot pursuit. The grace and agility of the shark was awesome and the view looking down into the water was unique to say the least. The speed and athleticism of the shark, and seals, was truly something to behold.
The sharks movement underwater can best be compare it to a F16 fighter plane twisting and diving in the air in perfect synchrony.
It also gave me an even greater respect to the seals who are able to half the time avoid this super predator doing what it has evolved to do so efficiently over time.
I have a feeling that this unique view may be one of my highlights of the 2012 Shark Season at Seal Island.
And, the seals got away ….
Shark Interaction at Predation Events
When a shark makes a successful kill it normally consumes the seal carcass within seconds. There can often times be high concentrations of sharks together in a small area when they are hunting seals at Seal Island. It’s the threat of losing a meal to another shark that causing this very quick eating behaviour. It does not happen very often that we are aware of but twice this month we had a second shark approach a successful predation and eat part of the carcass that had been torn off, the result was 2 sharks feeding on the surface at the same time just a few meters apart. I really would have liked to have had an underwater view of what was happing down there in order to view the behaviour displayed between the two sharks. We hardly ever get to see this, so to see it twice was exciting.