offshore dive site in False Bay, Western Cape, South Africa

The dive site York Shoal is an offshore rocky reef in the central part of False Bay, near Cape Town in the Western Cape province of South Africa.

Understand edit

 
Map of the reef at York Shoal
See also: Diving the Cape Peninsula and False Bay#Understand

York shoal is very seldom dived by recreational divers, because it is fairly far from the launch sites, near a known feeding area for great white sharks, and is virtually unknown to the diving public. Some will dive it because it is there, and to gather more information. Scientific diving may occasionally occur for various reasons, including surveys of the reef life.

Position edit

  • S34°09.367' E018°35.583' 1 York Shoal, 13.7km bearing 077° magnetic from Miller's Point and 24.3km bearing 293° magnetic from Harbour Island, about 2 km SSE of Seal Island

This site is not in a Marine Protected Area. A permit is not required.

Name edit

The name "York Shoal" is marked on the nautical charts of the area.

Depth edit

Maximum depth is about 28 m at the edge of the adjacent shingle bottom (smallish loose rocks, usually rounded by the action of water), and the top of the reef is about 4 m. Average depth of a dive is likely to be about 18 to 20m m.

Visibility edit

Visibility is likely to be whatever is prevalent on the west side of False Bay at the time. The site is far enough offshore to not be much affected by coastal effects, and is in a reasonably sheltered area for swell with a westerly component. On a sunny day the surface water may well have an algal bloom, particularly since the shoal is near to Seal Island, and the water is likelier to be richer in nitrates than average. If there is an algal bloom, the deeper water may be quite a bit clearer than near the surface, but it may be quite dark at depth. There is less kelp and other seaweed at the top of the reef than one might expect, and this suggests that the light levels are consistently low. There is insufficient data to be sure.

Topography edit

The reef is hard sedimentary rock with strike roughly east-west and dip about 10 degrees to the north, consequently the relief is mainly low flattish ridges and gullies, with no known steep or high dropoffs.

Geology: The geology is not known. For some time it was suspected to be peninsula granite, due to the proximity to the obvious granite outcrops of Seal Island, but the reef is clearly durable sedimentary rock, some of which is dark grey and fine grained. It has a similar feel to the reef of Table Bay, which is known to be Pre-Cambrian Tygerberg formation, and the proximity to Seal Island supports this conjecture, as it is below the level of the top of the nearby batholith, therefore likely to be older.

Conditions edit

Get in edit

See also: Diving the Cape Peninsula and False Bay#Boat dives

Boat access only: the site is several kilometers offshore.

The site is about 13.7 km from the Miller's Point slipway, 15.8 km from the Simon's Town jetty, 24.6 km from Gordon's Bay Old Harbour,or 23.8 km from Harbour Island in Gordon's Bay

See edit

Marine life edit

See also: Diving the Cape Peninsula and False Bay#The marine ecology

The shallower part of the reef is dominated by heavy growth of red-bait ascidians, with patches of black mussel, quite probably the invasive Mediterranean mussel. Also moderate numbers of sandy anemones, striped anemones and false plum anemones, and some gorgonian sea fans, which become more common at greater depths. Hottentot seabream and klipfish are fairly plentiful.

Photography edit

Not a particularly scenic dive, and visibility is unpredictable, so macro may be the best bet.

Suggested Routes edit

Not enough is known about the site to recommend any routes.

Stay safe edit

See also: Diving the Cape Peninsula and False Bay#Stay safe

Hazards edit

The site is in an area known for the number of Great White sharks, and near a known feeding area for these apex predators.

Skills edit

No special skills recommended. There is a large area above 18m and therefore suitable for entry level divers.

Equipment edit

See also: Diving the Cape Peninsula and False Bay#Equipment

No special equipment required, but it is a large reef and if you surface away from the shotline, a DSMB will be useful to make your position visible while ascending and when you reach the surface.

Nearby edit

 
York Shoal and other offshore dive sites of False Bay

Other offshore dive sites of False Bay:

Back to the Alphabetical list of sites, or list of reef dive sites in the northern False Bay offshore area

Other regional dive sites:

This dive guide to York Shoal is a usable article. It has information on location and equipment as well as some complete entries on what to see. An adventurous person could use this article, but please feel free to improve it by editing the page.