Mokarran Dive Charters at Rocktail Dive Centre








South Africa's most exclusive diving!

July 2012 Newsletter

Winter signals the Humpback Whale migration and we are fortunate to be able to see these majestic creatures every year during this time. These humpback whales live in the Antarctic but as winter approaches they are forced to begin their migration and move to warmer waters. They move between their feeding grounds in the Antarctic to their breeding grounds along the eastern side of Africa as far northwards as Madagascar.

There are a few reasons for this migration. One reason is that humpback whales are air breathing mammals just like us and even though they live in the ocean they need to surface to breathe air. During winter the Antarctic gets colder and more and more ice forms, covering the surface of the ocean. If the whales do not leave they risk being completely surrounded by ice and could end up trapped under the ice with nowhere to surface and breathe. Another reason is that they leave the colder waters for warmer waters to mate and have their babies. Why don’t they just live in the warmer waters? Well, their main food source is krill and this is found in abundance in the icy waters in Antarctica, warmer waters do not produce an adequate supply of food for these whales. The whales feed as much as they can before their long journey and have a thick layer of blubber in which they store this energy as this has to last them until they return to their feeding grounds months later. Humpback whales loose several tons of weight during this migration and mothers that are feeding their calves can loose up to a third of their body weight!

We were spoilt with some wonderful sightings of humpback whales this month, lots of them travelling in loose groups, with a few sightings of individual whales. We have not seen any babies yet but there have been quite a few “teenagers” still travelling with their moms.

One really exciting encounter was at the beginning of the month, we had seen a few whales and then we saw a big splash as a whale breached. As we travelled along we saw that there were two whales but that was not all, they were accompanied by four Risso’s dolphins! These dolphins are the biggest dolphins that you find in the world, they grow up to four metres in length and can weight between 300 - 500kg! When we saw the first one we thought that is was a tiny newborn whale, then we realised what it was, we were not even thinking about dolphins because other dolphins are not nearly that big. Risso’s dolphins tend to live in deeper waters, preferring to be in areas just off the continental shelf and are therefore not commonly encountered in shallow waters. Even Darryl, in all his years out to sea, had only seen these dolphins less than a handful of times, so a very rare and special sighting for everyone!

Diving this month was good even though proper winter conditions have set in. Water temperatures have dropped to 21 degrees Celsius and visibility averaged around 15metres.

Tillmann Gerding had a wonderful Discover Scuba Diving experience at Aerial. It was just Tillmann and Ondyne on the dive and they were lucky enough to get to watch two octopuses mating. Ondyne spotted the octopuses which were very well camouflaged as they tried to blend in with the seaweed; they were the same colour and even the same texture. As soon as the octopuses realised that their disguise was not working they moved slightly away from one another and flashed varying colours across their bodies but once they realised that the divers were posing no threat to them they moved slowly closer together and went back into “seaweed” camouflage mode. Octopuses are capable of changing the colour and texture of their skin to camouflage themselves and hide from potential predators and prey. They have specialised cells in their skin called chromatophores that are responsible for the incredible colour changes. If their camouflage does not work, they use deimatic behaviour, which is when they “flash” their colours as a warning in an attempt to scare the perceived predator away. If this tactic does not work they will squirt out a jet of black ink to “blind” or distract the predator as they swim away. These octopuses tried to scare the divers away at first but when they realised that there was not threat they proceeded to continue with their courtship. The male tentatively reached one of its tentacles out and laid it on the female, she moved slightly away and he tried again. Finally she allowed him to place his specialised tentacle called a hectocotylus into her mantle cavity and insert his spermatophores (packets of sperm). Sadly, the males die within a few months of mating and the females die shortly after their eggs hatch.  In fact, octopuses live for a relatively short period of time – in some species as little as 6 months. Another interesting fact about the octopus is that they have 3 hearts!  They are one of the most extraordinary creatures to watch and are known to be amongst the most intelligent of all invertebrates.

The Westcott family were the only divers during the last few days of the month and they were spoilt with wonderful ocean experience memories of a large pod of humpback whales that put on a spectacular display, as well as having some wonderful dives. Antonia, who had just completed her dive course in the UK, did fantastically on her dives – even though her first dive was a bit surgy, she coped very well – well done and wishing you many more wonderful dives.

Congratulations to the following divers:

Elise Legallet; Phill Black; Tillmann Gerding; Stuart, Will & Alex Wilson

for completing their PADI Discover Scuba Diving course

 

Paul Legallet & Sue Black

for completing the pool session of the PADI Discover Scuba Diving course

 

Yours in diving,

Darryl, Clive, Michelle, Ondyne, Mandla, Sipho

The Rocktail Dive Team

 

 

Accommodation bookings - contact our sister company Dream Dive Tours

Testimonials

  • "Fabulous. Dolphins, humpback whales, green and loggerhead turtles, guitar shark, pineapple fish and the legendary friendly potato bass and oh so much more - what more could a d..."
    Sarah Shephard
    Happy wife.......
  • "The dives were superb and I was totally blown away. I still sits as the #1 spot to dive. And the service and spectacular. "