Diving the Cape Peninsula and False Bay/Shark Alley
The dive site Shark Alley is an area of inshore rocky reef in the Castle Rocks restricted area on the False Bay side of the Cape Peninsula, near Cape Town in the Western Cape province of South Africa.
This is the best site near Cape Town to see Cow sharks. The only other site where Cow sharks are frequently seen is the adjacent site Pyramid, though they have occasionally been reported from other sites in False Bay.
S34°14.21’ E018°28.60’ Estimated
Inshore of Pyramid rock between Rumbly Bay at Miller’s Point and Castle Rocks.
This site is in a Marine Protected Area (2004). A permit is required. The site is entirely inside the Castle Rocks Restricted Zone.
The name "Shark Alley"refers to the Cow sharks Notorhynchus cepedianus frequently seen at the site, and the topography of the site, which is in the form of a relatively deep sandy bottomed alley between the shore and the higher reefs at Pyramid, a little further out.
Maximum depth is about 12m, with an average of about 8m in the alley.
Big granite corestone boulders and outcrops with sand patches. Fairly dense kelp forest on the near-shore reef and the reef surrounding Pyramid rock, and more sparse kelp on the rocks in the alley. The south end of the alley has many fairly large boulders, and lots of smaller boulders and outcrops with occasional sandy gaps. Further North it opens up with larger sandy gaps until there is more sand than rock. The rocks outcrops in this area are like small islands in a sea of sand. The sand is coarse and clean and light. This sand patch extends a considerable distance to the north east, getting wider the further you go. The sharks seem to favour the south end of the alley, or it may be that because it is narrower, they tend to be more easy to find there as they cruise up and down the alley.
Geology: Granite corestone boulders of the Pre-Cambrian Peninsula pluton, and wave rounded sandstone boulders from overlaying formations.
Usually considered to be a winter dive but there are also occasional opportunities in spring and autumn. The site is well sheltered from north west wind and chop. Swell from the south west or south east will cause surge. Judge by the conditions at the entry point and the colour of the water further out.
Parking at the side of the road is not very secure, and you also have to take into account baboons, which may investigate your vehicle in the hope of finding food. Lock the car and put any valuables where they can not be seen.
The site may be dived from shore or boat.
Shore entry: Parking at the side of the road. The usual entry point is at a small rocky beach just inshore of Pyramid rock and north of Castle Rocks at a position along the shoreline at S34°14.288’ E018°28.537’. Check out the pathways leading down to the shore before kitting up, as some are worse than others. All are steep and slippery when wet, some are dangerously so.
The shore entry is over some small rounded boulders on the beach, and bigger ones in the water, and can be a little tricky if there is a swell, as this results in a small shore break which can be troublesome if you are carrying a large camera with strobes.
An alternative shore entry is from Rumbly Bay. Entry at the old slipway at the Cape Boat Club. This access can be risky if the slip is in use. Keep a good lookout for boats being launched or recovered, they may not be able to keep clear of you, as the channel is narrow and shallow, with rocks and heavy kelp to both sides, and swell and cross winds to contend with, so stay well away from them and out of the boat lane. The route is either around north of the exposed rocks, along the edge of the boat lane, then follow the edge of the kelp until you are in the alley, or cut through the gap south of the exposed rocks, which is much safer, as boats do not go there, but more effort, as the kelp is heavy, and navigation is by compass. The slipway can be very slippery due to algal growth below the high tide mark.
Boat dives at this site have recently become more popular as many divers do not like the shore access, particularly when carrying cameras. Boat access requires care due to the kelp forests offshore of the site. There is a sandy gap between the north side of Castle Rocks and Pyramid which extends near to the shore and which is relatively clear of kelp, and the site can also be approached from the north east through an area with sparse kelp, which is the far north part of the alley. This does not appear to bother the sharks.
There are extensive kelp forests of sea bamboo, and a relatively large variety of fish may be seen, the most prominent being the Cow sharks, but Spotted gully sharks, Red steenbras and Bank steenbras are also seen here. Cow sharks appear to favour this site, and there is a significantly better chance of finding them here than any other known site in this region. Multiple sightings are common, and there have been occasions when four or more Cow sharks have been in view simultaneously.
Good site to photograph sharks. Water clarity is seldom more than 8 to 10m, and often less, and particulates will cause backscatter, so ambient light is often used. However the sharks will often approach very close to the diver, so wide angle lenses can also be useful.
The dives at this site involve getting to Shark Alley, and hanging around waiting for sharks. You can find sharks by looking for them, but you will see more fish if you wait quietly at a suitable place, and the sharks will come to you. They seem to like a close view and in some cases will pass within arms reach. It has never yet been necessary to fend them off. If you swim towards them they will usually swim away, very quickly if startled.
Shore dives: Entry at rocky shore below the road north of Castle Rocks point. There is a large flattish sloping rock which is good for exits and for entry if the tide is high. At low tide enter slightly south of this point where the kelp is most open. Surface swim about 80m through the kelp to the gap between the inshore forest and the Pyramid reef forest. Descend and work your way north and back and forth between the kelp forests. If you find a large relatively isolated rock with small bare rocky patches at its base, this is a good place to wait for fish. The alley is a bit over 200m long.
If you swim below the kelp to get to Shark Alley, use a course of about South East magnetic, follow the southern edge of the kelp for about 80m and turn North East when you come to a group of rocks with kelp on top extemding a bit to the south into the sand tongue. It may be necessary to surface to see where you are, as there are few easily recognisable landmarks. Those which may help are sand patches, relatively sparse kelp and a sudden increase of height of the rocks on the far side. There is a pinnacle of moderate size in the alley which is close to the southern end. Sharks and other fish are often seen in this area.
Boat dives: Adapt the route to suit where the boat drops you off.
The shore access can be tricky, and technically the Cow sharks may be considered a hazard, as they are large and have cutting edged teeth as they feed on seals. This does not stop many divers.
There are groups of people who prowl the parking areas of this site on the main road. They have broken into several cars, and stolen either contents or the whole vehicle. It would be prudent to get someone to watch the car or hire a car guard. Also don't leave your car with valuables visible through the windows.
No special skills required. Much of the time during a typical dive may be spent kneeling on the sand patches waiting for sharks to come past. Reasonable fitness and agility is recommended for shore entry, whereas boat access is OK for anyone who can get back on the boat.
No special equipment is necessary.