Hey Guys

I have finally gotten printed a few pieces of clothing printed.

Please have a look.

The T shirts are R120

Green sleeved shirts are R140

Hoodies are R250

This excludes shipping

Seal diving T shirts and sleeves shirts

Cowshark diving T shirts

Its all very well getting in the water sharks, but its important to understand what they are and who they are. Here is some information gleaned from the web and scientific papers about our Sevengill Cowsharks as well this family of sharks.

What is a Cowshark?

Cow sharks, or the Hexanchidae, are a family of sharks characterized by extra pairs of gill slits. There are probably only two seven-gilled genera, Heptranchias and Notoryhncus

Cow sharks are considered the most primitive of all the sharks, because their skeletons resemble those of ancient extinct forms, with few modern adaptations. Their excretory and digestive systems are also unspecialised, suggesting that they may resemble those of primitive shark ancestors. Their most distinctive feature, however, is the presence of a sixth and, in two genera, a seventh, gill slit, in addition to the five found in all other sharks.Cow sharks are ovoviviparous, with the mother retaining the egg-cases in her body until they hatch.

There are just four species of cow shark, in three genera

• Genera Heptranchias
  • Sharpnose Sevengill shark Heptranchias perlo
• 
• Genera Hexanchus
  • Bluntnose sixgill shark, Hexanchus griseus
  • 
  • Bigeye sixgill shark, Hexanchus nakamurai
  • 
    
• Genera Notorynchus
  • Broadnose sevengill shark, “Notorynchus cepedianus
  • 

    Jean Tresfon

The Broadnose Sevengill Cowshark, Notorynchus cepedianus

This is the Cowshark we find along our coastline and the specie dived with at Millers point. It is called a number of names Cowshark, Sevengill shark or the full length Broadnose Sevengill cowshark, which has one too many descriptive nouns for my liking. We mostly just refer to them as Cows ! Not a very frightening name to attract shark divers. This shark is the only existing member of the genus Notorynchus, in the family Hexanchidae.

What does it look like?

The Sevengill Cowshark is gray or brownish with spots. It is very common in the kelp forests around the Cape. It is easily distinguished from the other common kelp dwelling species, the spotted gully shark, by its lack of dorsal fin and rounded head.

Steve Benjamin swimming with a Sevengill Cowshark by Jean Tresfon

Sevengill Cowsharks can be found on the continental shelf, often in shallow water. Occuring very close inshore, in bays and estuaries, with larger individuals ranging into deeper waters offshore and deep channels in bays. In tropical to temperate waters; except North Atlantic and Mediterranean Sea. Southwest Atlantic: southern Brazil to northern Argentina. Southeast Atlantic: Namibia to East London, South Africa. Western Pacific: southern Japan to New Zealand. Eastern Pacific: British Columbia, Canada to Chile. Record from India maybe erroneous.

Distribution map of the Sevengill Cowshark

What do Sevengill Cowsarks eat?

The sevengill shark, Notorynchus cepedianus, is a versatile and common predator that has often been overlooked as an important marine predator capable of feeding on a wide variety of prey species. Stomach content analyses were performed on specimens from California, USA, and southern Africa to investigate whether dietary differences occur in relation to sex and size. Of the 531 specimens examined, 365 (68.7%) contained prey items. The dietary trend with growth and maturity shifted from fish to sharks (chondrichthyans), with marine mammals becoming increasingly important in the larger size classes of N. cepedianus . Small N. cepedianus (<120 cm total length, TL) fed primarily on teleosts, whereas larger sharks primarily consumed chondrichthyans. Marine mammals made up about one-third of the diet of N. cepedianus >220 cm TL, while teleosts declined to 6% and 13% for male and female sharks, respectively. A decrease was observed in the dietary overlap of each successively larger size class. Ontogenetic changes in the diet of N. cepedianus may provide insight into understanding how adults enhance the survivorship of their young, who are often less experienced at foraging for prey and are more vulnerable to predation.

Sevengill Cowshark tooth

When are Sevengill Cowsharks sexually mature ?

Maturation in male sevengills begins at about 140 cm total length (TL). Most males mature at approximately 160 cm TL. Male sevengills have viable sperm throughout the year and seem capable of reproducing year-round. Females have a complex and prolonged maturation period and mature at a size in excess of 218 cm TL.

What are the threats to Sevengill Cowsharks?

In south africa these sharks are caught as part of the demersal shark fishery as well as a species targeted by recreational fishermen. Cowsharks are not protected and anyone can capture and kill a shark as long as its not in a marine reserve. These sharks are sometimes used as bait in the White shark industry.

In South Africa Cowsharks are the apex predator in their habitat, and once the reach maturity only a great white shark or Ocra would prey on them. The following is an abstract details such an attatck by Orca’s in Argintina.

On 21 December 1998, four killer whales (an adult male, two females or immature males, and one juvenile) attacked a group of sevengill sharks (Notorhynchus cepedianus) off the coast of Caleta Malaspina, Chubut, Argentina. Persecution, catches, and tossing behavior were performed by the two females or immature males in the inlet. Next day, carcasses of several sharks were found on the beach adjacent to the attack area. Seven of them were intact and sized approximately 2.5 m in length. The presence of complete sevengill shark carcasses on the beach suggests that they were attempting to avoid capture by the killer whales by stranding on the beach. Attacks on sevengills by killer whales in Caleta Malaspina are frequent in some years, especially from mid-December to mid-January when the sevengill seems to use the inlet as a nursery ground. The observation of the same male feeding both on pinnipeds in Peninsula Valdes and on sharks in Caleta Malaspina may indicate that at least some groups in the Southwestern Atlantic could regularly feed on both fish and marine mammals. This is the first report of an attack of killer whales on sharks off the coast of Patagonia, and the first report of toss- ing behavior in sharks.

Where  can I dive with these sharks?

The best place to dive with these sharks is in Castle Rock Marine reserve at  Miller’s point, Cape Town. This part of the peninsula coastline is below the Swartkopberge mountains. The small rocky peninsula of Miller’s Point juts out rather abruptly into the bay and provides a sheltered site for the slipway from which most of the boat launches in this area are made. There is sufficient reasonably level ground for extensive parking areas off the main road, including boat trailer parking.

Map to the Cowsharks of Cape peninsular, Cape Town

This area is characterized by granite reefs with sandy patches between them, and almost flat sand bottom further out. Many of the reefs are fairly large areas of massive ridges, gullies and occasional loose boulders on top, and some of these boulders are huge. The cowsharks stick to the kelp channel just 50m from the shore. One can shore dive or boat dive this site (Source)

Jean Tresfon

When can I dive with these sharks ?

There sharks are present year round with the best periods being Spring and Autumn. The best vis is during winter but storms can make conditions undivable for long periods. During summer there are many sharks but the strong trade winds make the visibility quite poor. Due to the relatively protection of the site it is divable most days of the year. We have had great shark dives in vis as low as 2m !

Water temperature during winter is usually between 13°C and 17°C, though it has been known to drop as low as 11°C, so a good suit is also needed here. In summer the temperature may rise above 20°C, but is more likely to be around 17°C to 19°C. (Source)

What should I do while diving with Sevengill Cowsharks ?

Sevengill Cowsharks, although generally docile, are large predatory animals capable of inflicting bodily harm to humans if provoked. Therefore a strict code of conduct must be adhered to when diving with the sharks.

• – No touching.
• – Divers should not interrupt swimming patterns of the sharks
• – Avoid boxing in of a shark,  between two divers, or between a diver and a rocky outcrop.
• – No bait or chum is to be used when diving with the sharks.
• – Buoyancy control – you may get in a shark way or bump into a shark if you cant yet dive correctly.

Jean Tresfon

Last week Tuesday, 11 interns from the volunteer Adventure Corporation (VACorps) went out to False Bay to join Steve Benjamin, and Animal Ocean. The weather turned out to be absolutely perfect, for a day on the water. After launching the boat from Miller’s Point, we set off towards Seal Island to check out the seals. About 15 minutes into our trip, we spotted diving Gannets in the distance and decided to check it out. What we found however was a 1000 strong, pod of common dolphin! The water was white with moving dolphin, and the sound of 1000 dolphins echoed all around us. What and incredible experience! It didn’t stop there though however, after a stop at the biggest Cape Fur seal colony in the area, we then made our way over to Pyramid Rock for a dive with the Cow Sharks. The water was top to bottom visibility, pancake flat, and we were surrounded most of the dive by at least 15 Cow sharks, ranging from 1m to 2.5m. These impressive creatures let us swim amongst them for a good 40 minutes. What a day to remember! (Text from VACorps newsletter)

Volunteer Adventure Corps

I put this short video together to try show you what diving in Cape Town can be about. I also wanted to thank all the great people who share my life and passion for life, be it on the water or land. Live life to the fullest everyday…….

Have a look…

Mid March saw the freediving duo of the newly formed Ocean Encounters, 3x World Champion Fred Buyle and No fins dare devil William Winram arriving in Cape Town to a great weekend of weather. We headed out to the seal Duiker Island seal colony were we found cool 11C but clean water. We joined a playful group of 4 month old seal pups in the shallow secure waters near the island.

Fred Buyle with the seal pups of Duiker Island

William Winram with a playful pack of pups

These pups were born in Nov/Dec last year and seemed excited to play with the divers. It was time to warm up with some hot coffee while we searched for the next diving experience. It wasn’t long till I noticed a bird activity and a shimmering water surface a few kilometers offshore, it was a large pod of common dolphins!

Fred Buyle with a pod of common dolphins near Hout Bay

Attracted buy the possibility of riding our bow wave, they surrounded us. A magical experience right on our door step

The next day we headed to pyramid rocks to dive with the sevengill cow sharks. The light NW wind had brought in quite a bit of cloud cover so we dived while we waited for better lighting. The water was a massive 2 degrees warmer but slightly greener. With just about 10m vis, if I looked carefully I could see the sharks swimming on the bottom. The cowsharks did no disappoint with up to 15 sharks being present at the site.

Fred Buyle and William Winram with the Cowsharks

We dived until we were chilled to the bone and once again some hot coffee saved the day.
Considering the difficult ocean conditions we have been having lately the guys had a wonderful gap in the weather and some good diving.

On February 5th, after another dive with the seven gill sharks (or cowsharks, as they’re called here) off of Miller’s Point, Steve Benjamin (Animal Ocean) took me up to Cape Point at the Cape of Good Hope, the most south-western point of Africa.  Although it’s not the tip of Africa, it’s definitely the photogenic tip of Africa, and Steve and I had a good time taking pictures and hiking up to the new lighthouse.  We saw ostriches and baboons as well!

Myfanwy Rowlands at Cape Point

In the afternoon, we toured the Kirstenbosch Botanical Gardens, which are absolutely stunning.  So much botanical knowledge in one place, it was mind-boggling and academically very inspiring — but to those friends who are all-too-familiar with my vocational ADD,  I’m happy to report that despite the amazing visit I’m still planning on studying marine biology & conservation, not botany.  Although I do have my sights set on marine plants.

For the past three days (Feb. 6-9), I’ve had the privilege of accompanying Thomas Peschak, Chief Photographer for the Save Our Seas Foundation, on an underwater photo shoot here in Cape Town.  We’ve been out every day on Steve Benjamin’s Animal Oceans boat, and it’s been amazing to watch such a high-calibre photographer at work.

Thomas is also a tremendous advocate for shark conservation and a member of the International League of Conservation Photographers;  I would not have been able to come to South Africa if it weren’t for his help in finding experiences in South Africa for me on my scholarship.

Today the swell was up, so Steve Benjamin (Animal Ocean) and I took a group of professional photographers out chasing the big wave surfers at Sunset Reef, a surf spot here in Cape Town with a reputation almost as deadly as Dungeons.  We were out there for half the day, and I was absolutely blown away what these guys can do on the water.  Below is a picture by Jean Tresfon — the surfer is Sean Holmes, one of South Africa’s finest big-wave surfers.

The waves were unbelievable.  Browse below if will, and try and imagine riding down the face of one of these.  Also out there today were Mike Baleta, Simon Lowe, Dave Smith and Mickey Dufus.

Sean Holmes first wave on the tow at Sunset

Over the falls

I received this email a few weeks ago “Hello!  My name is Myfanwy Rowlands. I’m currently traveling on a diving and marine educational scholarship sponsored by Rolex and the Our World Underwater Society.  I was hoping to see whether my volunteering with your organization would be a possibility?…….” I had heard of the programme and was very happy and honored to be involved. How could I say no?,a chance to show some one around the city and ocean I enjoy so much, maybe she would be able to keep up!

A little history from the Our world – Underwater society scholarship’s website -
Each year the society awards year-long scholarships designed to expose a qualified young person to a wide range of experiences in various marine-related fields. With continued generous funding from the Rolex Corporation, the awards are now known as the Rolex Scholarships.

For 2010, three Rolex scholarships will be offered: one in Australasia, one in North America, and one in Europe. Each Rolex Scholarship provides a hands-on introduction to underwater and other aquatic-related endeavours for a young person considering a career in an underwater-related discipline. One scholar is selected from each of the three regions and each scholar spends approximately one year working side by side with current leaders in underwater fields. Each scholar travels primarily within his or her region, but may have opportunities throughout the underwater world. The range of experiences may include active participation in field studies, underwater research, scientific expeditions, laboratory assignments, equipment testing and design, photographic instruction, and other specialized assignments.

I wanted to give her a chance to see and meet as many people as possible, needless to say she hit the ground running. She arrived from Tasmania after a 23 hour journey only to find herself being taken to Dassen Island, a place she had never heard off and certainly not on the tourist maps. Here is what Von has had to say about some of her experiences with me in Cape Town so far (Source) -

Wow!  First blog update in awhile, sorry — you can blame Steven Benjamin, my awesomely over-achieving local Cape Town host, for that.  We’ve been on a whirlwind tour of Cape Town’s aquatic environments, and I’m going to post about them individually in the next few days!  Steven runs Animal Ocean, an all-inclusive ocean eco-tourism operation that offers personalized outdoor marine and aqua experiences.  Spearfishing, freediving, shark diving, photographic excursions — you name it, if it’s in the ocean in the Cape Town area, Steve’s probably an expert in it.   Let’s just say that today I had a bunch of 1.5m-long cowsharks swimming around my head, and I’m absolutely loving life.

29 Jan 2010

Right!  So I’ve got some backlogs to do, starting with the day I arrived in Cape Town, South Africa.  I was met at the airport by local dive and underwater guru Steven Benjamin, who operates Animal Ocean, which is an all-encompassing marine eco-tourism operation.  We had some breakfast, and then Steve whisked us off to Dassen Island with 25 University of Cape Town’s 2010 Zoology Honours students.  Dassen Island is a special place – it’s managed by the Nature Conservation, South Africa’s government environmental agency.  No one is allowed on the island without a permit, so we were very, very lucky to be able to go.  The island itself is a haven for bird life, including penguins!  The history behind the penguins of Dassen Island is tumultuous; because their eggs were harvested aggressively until the 1960s, their numbers are reduced now to less then 10% of what they were at the turn of the century

Dassen Island research accomadation tucked behind the dunes

Myfanwy Rowlands at Dassen Island

True Dassen Island locals....

Penguin wall

This picture shows the Dassen Island lighthouse and a portion of the penguin wall that was constructed years ago and encircles the entire island.  It was built to keep the penguins from building their nests too far inland and facilitate easier collection of their eggs.  It’s now breached in numerous places and the penguins have no trouble getting to the interior of the island.

1 Feb 2010

Steven Benjamin (my Cape Town guide and owner of Animal Ocean) and I returned from Dassen Island on Sunday, March 31st.  On Monday, Steve took me along on one of his dive charters to Duiker Island, home of a very friendly colony of Cape fur seals.

Cape Fur seal leaps from the water at Houtbay

They were magic to dive with, but seals always make me feel like an absolute robot underwater.  After the dive, Steve took us snorkeling to a little rocky beach just beyond the point of Hout Bay Harbor, because he wanted to show us the site of an abalone poaching operations.  The picture below shows the pile of empty abalone shells we found there.

A pile of poached and scraped abalone shells.

What happens is, abalone divers go outside the harbor in little rubber duck boats, collect the abalone and bring them to this beach, which is hidden from sight and around the point from Haut Bay slipway.  The poachers unload their illegally harvested abalone on the beach, stacked up in piles, before taking their now empty boats back to the slipways of Hout Bay Harbor, which are monitored for illegal abalone fishing.  Then the poachers hike over the point down to the beach, and carry the illegal harvest of abalone meat overland, thereby avoiding getting caught.  It’s quite a racket.

2 Feb 2010

The one day that should of been 6  !!!!

What an amazing day February 2nd was.   I’ll take you through the pictures below and explain the chronology that way. I tagged along with Steve Benjamin (Animal Ocean) on a dive charter to dive with a natural aggregation of seven-gill sharks, or cowsharks (as they’re called in Cape Town) just past Miller’s Point near Simons Town.  It’s an unbelievable spot, as the cowsharks are gathered there in significant numbers and they’re VERY curious… not at all shy of divers.  It was fantastic!  We had at least 7 sharks around us at any one time, and we reckon we saw about 20 total.

Sevengill Cowshark - Image by Sjimon de Waal

After the cowsharks, we stopped at the boat ramp at Millers Point to see the snoek boats coming in.  The picture below is of a man counting the snoeks as he tosses them in a bucky to be carried to market.

A good days catch of snoek

Then we stopped by Muizenburg beach, and were just in time to see the Treknet fishermen bringing in a fresh catch of yellowtail kingfish!  This type of fishing is a bit different from your average industrial trawler or purse-seiner…the whole community gets out on the beach to help pitch the nets.  It was fun to watch.

Trek net fishing on fish hoek beach

We left Muizenburg Beach and drove up Boyes Drive to the overlook of Muizenburg in False Bay.  From there, you can see Seal Island (remember that AWESOME series in Planet Earth that shows great white sharks breaching?  That’s Seal Island), as well as the entire stretch of Muizenberg Beach.  To our unbelievable luck, the Shark Spotter on duty, (her name is Vivian) spotted  a great white just moments after we arrived!

Von and Vivian watch a great white shark swimming in the surf zone

It was unbelievable.   I’ve shown the picture below fully scaled out and then zoomed in to give you an idea of perspective – the shark was about 2.5m-3m long.  The Shark Spotter program is a wonderful alternative to shark nets (which can be found all along the eastern beaches of South Africa, in Durban).  Shark nets “work” because they kill everything in their path, shark and fish and dolphin and seal alike.  The Shark Spotter program works, and eliminates the unnecessary slaughter that shark nets unleash.

And that was (most of) our day!  It was banner.  The days have been packed, and I’m still catching up – more to come.

3 Feb 2010

February 3rd was the day that Steve Benjamin (Animal Ocean) and I went up into the mountains to meet Jeremy Sheldon, Ph.D. student at the University of Cape Town.  Jeremy is doing his Ph.D. thesis on the streams and rivers of the Bain’s Kloof region, in the mountains Northeast of the Cape.  He’s comparing the ecology of streams that have been invaded with trout (100 years ago they were brought over and introduced for game fishing) to that of those streams and rivers where trout haven’t infiltrated.

Jeremy Sheldon happy doing field work

Tierhok Rivier

A gorgeous, gorgeous day of fieldwork in a beautiful place.  I’m now seriously considering studying river otters along with sea otters.

One of the Netherlands most acclaimed award-winning underwater photographers, Peter Voerhoog, traveled to Cape Town with the goal of photographing blue sharks for his latest book “Sharks, close encounters”.

Sharks, close encounters by Peter Verhoog

Here are some of the images he captured while diving with us in the Cape

Dusky Dolphins play in the cool Atlantic waters off Cape Town

Cape fur seals in Houtbay harbor

Steve Benjamin and Sevengill cowshark

Blue sharks investigate Peter off Cape Point

Cape fur seals playing off Duiker Island, Houtbay

Peter in tough conditions in order to get the blue shark images

I am looking forward to this inspiring book and am proud to have played a small part in it

Steve

Hey guys

Its been awhile since my last blog entry. I find myself this evening with so many experiences I want to share and I dont know where to start. I always find its best to show people what we’ve been doing. So below I have chosen a few images from the last few weeks. The images come from a range a photographers to whom I am grateful.

Chapmans peak panoramic by Goeff Spiby

This image was taken on a photographic trip on the Atlantic seaboard. It really shows the beauty of being under Chapmans peak and the scale of the mountain. The wind was howling with this bay being slightly protected. I had to position myself in the lee of the granite boulders to keep the boat steady.

Bull and dead pup by Geoff Spiby

The seals have been pupping on Duiker Island, not all make it. Here we found a bull seal resting on a small granite boulder lying right next to young seals corpse seemingly oblivious to it. In the water we found many dead pups, most being scavanged apon by giant petrols and seagulls, the strong winds and waves washing possibly washing them off the island.

Steve Benjamin filming for Charles Maxwell at Duiker Island by Jean Tresfon

Trying to capture the seals swimming in thick kelp was tough but once one finds a pattern in the seeming chaos of swirling seals we got the shots.

Swimming seal by Jean Tresfon

Here Jean captured the seal just as it darted “flew” away

Chapmans peak, Geoff Spiby

We were traveling along the base of Chapmans peak, mostly trying to stay out of the howling wind, when we arrived at my faverite crayfishing spot. This turned out to be a well know location to others on the boat. We jumped into the cold but clean water to see what could be captured. These anemonies are covering the granite boulders in the shallows . One can see the mussel zone at the top of the rock.

Chapmans peak ledges Geoff Spiby

This was taken at the same location as the last image but just a bit deeper. You can see the small crayfish that dwell in these crevases. That crack at the top of the image used to hold huge crayfish but not anymore. The photographer in the background is Mark Van Coller.

Dusky Dolphins by Peter Lambert

Dusky dolphin pod by Peter Lambert

On this day we encountered the local pod of Dusky dolphins as they were aggregating. The can be a very inquisitive species of dolphin and came to investigate the divers.

Jellyfish by Jean Tresfon

There have been an abundance of Jellyfish on our coastline latley, which make beautiful subjects. It has also lead to the appearance of many sunfish.

Jean Tresfon Sunfish

Sunfish by Jean Tresfon

It took me awhile to figure out how to get photographers close to these small sunfish, they just kept swimming away. The larger individuals seem to be less skittish and easier to work with, but also less common. We encountered up to 5 small individuals at a time and got extremely close in often dirty water.  Here Jean Tresfon captures the beauty of a sunfish in Table Bay.

Jean Tresfon and Sunfish by Geoff Spiby

Here one can see that these are small individuals and Jean tries to get a close up with his wide angle lens

Sevengill Cowshark by Steve Benjamin

Although not a pro image I wanted to mention the Sevengill sharks. They have returned in full force.  We have done several dives there in the last week and I am always blown away. On one occasion I had 13 in my field of view, from the bottom to about 8m in the water column.On another dive I found seal remains (flipper, fur and intestine), Iether a seal carcas washed in or the Sevengills got hungry.

Well I hope you have gotten an idea of what I have been up to. There are some fun project in the pipline so get in contact to see what is going on and how I can help

Cheers

Steve

It was special day on Sunday in False bay, Glassy, great vis and warm. It was a real summers day with the vis of winter. We dived with the Sevengill cow sharks and seals most of the day. There were a lot of fishermen catching snoek nearby, however we didn’t catch anything. The entertainment coming from catching gurnards when someone got a birds nest and the lure stayed on the bottom to long.

It was just one of those days your happy to be alive. Here are a range of images from the day.

Thanks to everyone for the great times

Catshark video clip