Beaches a Diversity of Coastal Treasures CITY of CAPE TOWN BEACHES
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CITY OF CAPE TOWN Beaches A diversity of coastal treasures CITY OF CAPE TOWN BEACHES Published by the City of Cape Town First edition 2009 More information available from: Environmental Resource Management Department 7th Floor 44 Wale Street Cape Town Tel: 021 487 2284 www.capetown.gov.za/environment ISBN 978-0-9802784-3-9 This handbook is printed on SAPPI Triple Green paper, an environmentally-friendly paper stock made from chlorine-free sugar cane fibre to support sustainable afforestation in South Africa. Every effort has been made to ensure the accuracy of information in this book at the time of publication and to correctly acknowledge photographs. The City of Cape Town accepts no responsibility for, and will not be liable for, any errors or omissions contained herein. CITY OF CAPE TOWN Beaches A diversity of coastal treasures Contents 1 CAPE TOWN’S TWO COASTS 41 CITY SEABOARD 2 Upwelling 42 Granger Bay 3 Tides 43 Mouille Point 4 Rocky shores 44 Three Anchor Bay 6 Sandy beaches 45 Sea Point 8 Estuaries – Rocklands 10 Blue Flag – Graaff’s Pool 11 Shark-spotting programme – Milton Beach 12 Whale-watching – Brokenbath Beach 14 Threats to the coastal zone – Sunset Beach 18 Harvesting marine resources – Queen’s Beach 20 Sustainable seafood – Saunders’ Rocks – Consumer’s Seafood Species List 49 Bantry Bay 22 Early days on the Cape coast 49 Clifton –1st Beach 27 WEST COAST –2nd Beach 28 Silwerstroomstrand –3rd Beach 29 Van Riebeeckstrand –4th Beach – Duynefontein 52 Maiden’s Cove 30 Melkbosstrand 52 Camps Bay 32 Blaauwberg Conservation Area – Glen Beach – Eerstesteen 55 Bakoven – Derdesteen – Kreeftebaai 57 ATLANTIC PENINSULA – Kelpbaai 58 Oudekraal – Haakgat – Cosy Bay – Holbaai – Koeëlbaai 34 Bloubergstrand 60 Llandudno – Big Bay 63 Sandy Bay – Small Bay 64 Hout Bay – Bokkombaai 68 Noordhoek 35 Table View 69 Kommetjie 35 Dolphin Beach – Die Kom 36 Rietvlei Wetland Reserve – Long Beach 38 Sunset Beach 71 Soetwater 38 Milnerton 72 Witsands – Milnerton Beach 73 Misty Cliffs – Milnerton Lagoon Beach 74 Scarborough Penguins sunning themselves at Boulders Beach Contents 77 CAPE POINT 109 CAPE FLATS COAST 78 Olifantsbos 110 Muizenberg 79 Gifkommetjie – Surfer’s Corner 80 Platboom – Rocky Beach 81 Cape of Good Hope – Muizenberg Beach 82 Cape Point – Muizenberg Pavilion – Dias Beach – Zandvlei 83 Rooikrans – East Beach 84 Buffels Bay – Sunrise Beach 85 Bordjiesrif 113 Zonwabe and Cemetery Beach 86 Black Rocks 115 Strandfontein – Blue Waters 89 FALSE BAY PENINSULA 116 Mnandi 90 Smitswinkel Bay 117 Wolfgat Nature Reserve 91 Miller’s Point 118 Monwabisi 93 Fisherman’s Beach 119 Macassar Beach 93 Frank’s Bay 93 Windmill Beach 121 KOGELBERG COAST 94 Boulders Beach 122 Strand 96 Seaforth – Melkbaai 97 Simon’s Town – Mostertsbaai 98 Long Beach 124 Harmony Park 98 Mackerel Beach 124 Harbour Island 98 Shelley Beach 124 Hendon Park 99 Glencairn 125 Gordon’s Bay 100 Fish Hoek – Main Beach – Clovelly – Sunset Beach 102 Kalk Bay – Bikini Beach 104 Dalebrook 127 Steenbras River Mouth 105 Danger Beach 129 Kogel Bay 106 St James Beach – Kogel Bay Resort 107 Bailey’s Cottage – Klippies Bay – Spark’s Bay – Dappat se Gat Noordhoek beach Cape Town’s two coasts Cape Town’s beautiful coastline extends for 307 km along the West Coast, around the Cape Peninsula, and beyond False Bay to the Kogelberg coast in the east. The combination of the warm Agulhas current that sweeps down the east coast, and the cold Benguela current that flows up the west coast, results in an incredibly rich and varied marine flora and fauna. Its mild Mediterranean climate allows residents It is also the southeaster that is responsible for and visitors to enjoy the beautiful coastline all the marked difference in sea temperature between year round. While winter brings cold and wet False Bay and the coastal waters west of Cape weather, there is always a break in the rain long Point. Indeed, the West Coast and Atlantic Sea- enough for a brisk walk on the beach, and surfers board are often referred to simply as ‘the cold love the large swells generated by winter’s north- side’, and only the hardy can withstand more than westerly winds. a quick dip in the sea without a wetsuit. In spring and summer, warm and sunny weather The southeaster, which reaches galeforce at returns, but is accompanied by the prevailing times, pushes and pulls the surface layer of sea- southeasterly wind – popularly known as the ‘Cape water along with it. In False Bay, this has the doctor’, as it blows the city’s air pollution away. effect of piling warm water up along the coast, The southeaster flattens the swell, but whips up so summer water temperatures generally stay white horses further out to sea, and may give within the 16-22°C range. West of Cape Point, beach-goers a sandblasting if they do not find a the southeaster pushes surface water in a sheltered spot. Fortunately, many of the beaches northerly direction, but it is deflected offshore along the Atlantic Seaboard lie in the lee of Table due to the earth’s rotation to the east. Cold Mountain, and are well-protected from the wind. water from the dark depths of the ocean rises Clifton, in particular, is recognised as a fail-safe up to replace it in a process known as upwelling, option when the southeaster blows and dis- so sea temperatures typically hover in the courages people from the city’s other beaches. 10-15°C range. PAGE 1 Upwelling Upwelling makes for chilly swimming, but also ensures that the West Coast is South Africa’s most productive marine environment. Freshly upwelled water is a clear, turquoise colour because it contains no phytoplankton – i.e. microscopic plant life that needs light for photosynthesis. However, the upwelled water is rich in nutrients, especially nitrates formed as a by-product of the decomposition of organic matter, which constantly sinks down to the seafloor. The nitrates act as a fertiliser for phytoplankton, which soon form dense ‘blooms’ that are grazed by zooplankton. Both plant and animal plankton are consumed by pelagic fish, such as anchovy and pilchard, which are in turn food for larger fish, such as hake, as well as seabirds, seals and dolphins. The abundance of fish supports South Africa’s purse seine and trawl fisheries, while the region’s Rock lobster ‘walk-out’ on the West Coast dense kelp beds – also dependent on nutrient- rich water – provide habitat for West Coast rock sea becomes calmer and warmer, and these con- lobster and abalone. ditions are more suitable for phytoplankton Upwelling conditions favour phytoplankton blooms dominated by dinoflagellates – i.e. proto- blooms made up of diatoms. These large cells zoa that can maintain their position in the water often grow in chains, or have spiky shapes to slow by beating their flagella. As the dinoflagellate their sinking rate, and the turbulence generated blooms are concentrated by winds and currents, by upwelling helps them to remain in the sunlit they become so dense that they discolour the surface waters. Between upwelling events, the water various shades of red, orange, brown or purple, depending on the pigments within the cells. South-east Some of the species making up these so- wind called ‘red tides’ are toxic, and can be fatal to Warm surface water moves offshore human consumers of filter-feeding shellfish, such as mussels, clams and oysters, which accumulate the toxins in their tissues. Red tides can also Sun-lit surface suffocate fish by clogging their gills, and typically water Plankton bloom also result in low-oxygen conditions, as bacterial g l i n U p w e l Cold decomposition of decaying phytoplankton blooms nutrient-rich water uses up much of the oxygen in the water. Marine animals move into shallow water to escape the Dark deep water oxygen-depleted water, resulting in mass fish The upwelling process strandings and rock lobster ‘walk-outs’. PAGE 2 Tides The daily fluctuations in sea level, known as tides, Spring tides are extra-high and extra-low tides are caused by the gravitational force of both the that occur every two weeks throughout the year, sun and moon on the earth’s oceans (see figure a few days after new and full moon. At these below). The moon has the greater influence, as it times, the sun, moon and earth are in line with is much closer to the earth than the sun, so the one another, and their combined gravitational tides are said to follow a lunar cycle. pull creates an extra-large ‘bulge’ at high tide. The moon’s gravity pulls a ‘bulge’ of water A greater area of shoreline is exposed at spring towards it, causing high tides on the side of the low tides, which in South Africa occur at about earth closest to the moon. On the opposite side, 10:00 and 22:00. the water bulges out due to centrifugal force as Between the spring tides are neap tides, when the earth and moon spin around one another. the difference between high and low tides is not Since the earth rotates, each point will ex- as marked. Neap tides occur during the first and perience two high tides per day – one due to last quarters of the moon, when the moon is at gravitational pull, and the other due to right angles to the sun, and their gravitational centrifugal force. As the water bulges out in pulls cancel each other out. these areas, it is drawn away from others, The tidal range – the distance between the low- causing low tides there. water and high-water marks – varies enormously The moon takes 28 days to orbit the earth, from one part of the world to another, but in moving a little further round the earth each day.