June 2010 Shark Bytes
Posted on Wednesday, 30 June 2010
Dear Shark Lovers,
It has been quite a month so I suggest you grab a cup of something hot to drink so you can sit down, relax and hear all our news!
Apart from the Great whites being in full swing at Seal Island we have had great cetacean sightings including the Killer Whales again and we were able to sneak away for 5 days to try our luck with The Sardine Run along the Natal Coast. On top of that we volunteered in a Dwarf Pigmy Whale stranding and finally there is a heads up on Shark Week in August 2010.
Great White Sharks, Seal Island
June is on of our absolute peak months for Great whites at Seal Island and June 2010 certainly did not disappoint. From the start of the month the numbers of sharks around our boat have been on the constant increase with most trips averaging 8 sharks per trip and the busiest trip recording 13 different sharks. We have also been fortunate with some fantastic individuals that have really stayed long enough for everyone on board to have a great experience.
As a result we know have some new “sharky friends”. “Clover”, a 3 meter (10 foot) female has been a regular over the last part of June and she has no problem staying for long periods at the boat. “Topsie” is a 3.5 meter female that we sighted during the 2009 season. The top of her dorsal fin is slightly crimped making her easy to identify and she has been recorded on and off through June.
Some of you may remember the notorious “Cruella” from the 2008 season. I have to say that most sharks around the boat behave in a cautious manner and are pretty careful around the boat. Cruella is a completely different ball game and we really have our hands full in terms of keeping the bait away from her. Her tremendous rushes out of the water as she goes for the bait are a real crowd pleaser but I can tell you that the crew are sweating buckets when she is around! In fact Cruella’s claim to fame is that in 2008 she actually chased a BBC film crew home. They were after a very simple shot of a Great white shark dorsal very gently cleaving the surface of the water. They booked over a period when Cruella was in town and just could not achieve this really simple shot. On top of this Cruella would not let any other sharks stay for more than a few passes around our boat, so in the end they left early and flew back to South Africa a month later!
Cruella’s behaviour is highly unusual and we have not had too many interactions with any other sharks like her in the last 18 years. A shark with this kind of behaviour would be a prime target for getting herself into trouble so when we did not see her last season we were worried that something ominous had happened to her.
She does not have a lot of distinguishable markings so after this shark displayed “cruella-like” behaviour we were only able to identify her from dorsal fin ID photo records. We were over the moon to make this positive identification. We have now recorded her at 4 meters and although she has injuries from being pulled into the engines of another shark operator (very upsetting) she appears to be in fine form.
More good news is that we think we have had a return sighting from a shark we have called “Knight Rider”. We last saw this male in 2005 so it has been a long gap of 4/5 seasons since he was last identified at Seal Island. He has an extremely spotty left and right flank which is pretty unusual and at the size we have recorded him now (4.0 meters or 12.5 feet) it is almost certainly him. This is a shark that we would regularly see between 2003 and 2005 so it is very exciting to note his return after such a long absence. Good news is that he too looks in great condition.
As we get into the season we are on the lookout for our other regulars that still need to show themselves…
It has not been the busiest month for breaches on the decoy but this has started to pick up in the second half of June. The breaches are a funny thing…we mostly find that the sharks go through “breaching cycles” meaning that for 4/5 days they will breach on the decoy all day and then we may have another week when they do not breach at all. It is very important that we are responsible with this behaviour and we purposefully do not tow longer than 45 minutes to 1 hour each morning. This may result in a very maximum of 2 or 3 breaches, but sometimes none at all.
We are also starting to see signs that the natural predation activity on the cape fur seals is starting to pick up. We have seen events most days that have varied from mostly just one splash to a handful of prolonged chases. We have found that the natural predation patterns are different every season so we really need to be able to read the area and the signs to the best of our ability in order to observe these events.
As of now the sharks are attacking a lot of seal groups which is a little abnormal compared to the lone seals that they seem to have more success on. We will see what July brings!
OK, so if you have been following our Facebook page you will know that something a little unusual is happening in False Bay. In June there were no less than 4 separate Killer Whale sightings on 1, 5, 20 and 26 June.
We were at 3 of these sightings and have photos from a colleague from the 4th sighting. What is truly amazing is that we now have positive records of 5 different Killer Whale pods since April 2009. 1 pod has been observed on 3 occasions and the other 4 pods just once.
On all but one occasion the Killer Whales were travelling with schools of common dolphin and attempting to hunt them. The pod that we have seen more than once have completely different hunting strategies to each other and a third pod was observed killing, but not eating, two cape fur seals.
Another interesting observation is that only 2 out of the nearly 25 individual killer whales will bow ride with our boat. We have read that this kind of behaviour is rare for killer whales so it seems as though only a couple of them are comfortable coming close to the boat.
With these increased sightings we can’t help wondering if Killer whale sightings in False Bay will be become more regular and if there is communication between the pods that a viable food source, i.e. the dolphins, are present in the False Bay area.
There has been a tremendous amount of bait fish present in False Bay which has been keeping the dolphins in the area, who in term must be attracting the Killer Whales.
So, watch this space. We are now very aware of picking up on stressed dolphin behaviour and our expert spotters on board have got the Killer Whale Bug!
We have also had our first Southern Right Whales sightings and a couple pods of Humpback Whales...so False Bay has certainly been alive the last month.
Dwarf Pigmy Whale Stranding on Muizenburg Beach
Sadly on 2 June at 8.30pm we were alerted by friends from the NSRI that a mother and calf dwarf pigmy whale had stranded on Muizenberg beach. Although the dwarf pigmy whale is not a rare whale they are very seldom seen by people and most observations have been at strandings, particularly of a mother and calf together.
Cetacean strandings are very controversial in terms of why these animals strand and whether or not a rescue operation should be attempted.
Our personal feeling is that the oceans and all marine animals are under such serious threat that one good attempt at a rescue should be take place to give the animal a fighting chance if it is not ill and the stranding was an error.
The rescue operation that took place was in my opinion extremely well organised.
The whales were small enough to be stretched into the back of two 4x4’s and driven to Simonstown where they could be loaded onto a vessel. We volunteered White Pointer as the back of our boat was perfect to load 2 small whales and the open and low deck meant that we could easily release the whales back into the water.
Once the whales were safely loaded we headed to the mouth of False Bay where the whales could be released into the open ocean. We were lucky that it was a perfect evening with flat seas so the whales were not highly stressed during the travel time. On release both Mother and calf swam strongly from the boat and we really believed that the rescue operation could not have been smoother.
Unfortunately almost 18 hours later the 2 whales stranded at almost exactly the same stretch of beach and the right decision was then made to euthanize the animals. The fact that these whales were able to find the same spot to strand tells us that they were not overly stressed in the transporting but they had made a decision to strand and that was that. I know this is controversial but I still believe it was the right thing to give them one good effort after the first stranding.
The Sardine Run
The Sardine Run is a natural event that takes place most years along the Natal Coast. Normally a huge bio mass of sardines move up the East coast that sustains a large array of predators that rely on this food source moving into their area each year.
The high presence of predators such as Common dolphin, brydes whales, bronze whaler, dusky and black tip sharks and cape gannets means that extremely intense feeding events called bait balls will take place as the sardines move up the coast.
A common misconception is that these sardines are migrating up the coast. They are in fact merely moving with the Agulhas Current as it stretches up the east coast at this time of the year. The sardines are just moving with the current and are not migrating at all. They have no reason or purpose for moving up the coast but I guess nature is providing a very important food source for the waiting predators especially since it is vital for the young of the year dolphins to have their first good feed.
Chris & I have not been able to witness this great event before as it is peak time for the Great Whites at Seal Island. This year we were able to leave our shark trips in the very capable hands of our crew as we were very fortunately invited by friends to try our hand at The Sardine Run.
Even though we had the best and most experienced crew of Mark and Gail Addison from Blue Wilderness guiding us we still needed good luck to be in the right spot at the right time, and we only had 4 days to do it!
We stayed in a most spectacular location with fantastic friends near Waterfall Bluff, about 40 kilometres north of Port St Johns.
As we flew in we were treated to a tremendous view of the Wild Coast which is a notorious piece of dangerous coastline. My expectations for this adventure was that we would perhaps be able to spend time with the dolphins, whales and sharks and only if we were extremely lucky would we see a bait ball.