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epopulate the rest of the river system is low at present. In the estuary, some inshore marine fish populations may utilise the estuary as a warmer refuge during upwelling events (Lamberth 2003). The extent of this function in its contribution to marine populations is unknown. Estuaries are typically shallow and sheltered habitats that provide a refuge from the action of waves that are characteristic of the South African coastline, making them ideal nursery habitats for juvenile fish species, many of which are of commercial importance (Wallace et al. 1984). While estuaries are widely accepted as being among the most biologically productive ecosystems on earth (Kennish 2002), estuaries in the region where the Uilkraals is located are fed by oligotrophic (nutrient‐poor) rivers, and are thus not particularly productive. There are about 431 000 recreational fishers and well over 21 000 commercial fishers active in the inshore marine environment in South Africa. Commercial net fisheries (beach seine and gill net) on the south coast are likely to be the fisheries that benefit most from the Uilkraals Estuary. The commercial line fishery, recreational shore angling and recreational boat angling fisheries could also benefit to a small extent. Nursery areas are breeding habitat for populations that reside elsewhere. Estuaries provide nursery areas and habitat for numerous species of fishes which are exploited by recreational and commercial harvesting in the inshore marine environment. Different species are dependent on estuaries to different degrees for stages of their development and growth. Freshwater flow and the frequency and duration of estuary mouth openings are major factors affecting estuarine biota (Turpie & Clark 2007), and particularly the juveniles of marine organisms that use them as nursery grounds (Whitfield 1994, Strydom et al. 2003) either directly through habitat availability, or indirectly through their impact on estuarine productivity (Gillanders & Kingsford 2002). Factors that make estuaries suitable nursery areas are increased food, higher temperature, turbid waters and lower salinities, all of which can be changed by the variation in freshwater input (GiIlanders & Kingsford 2002, Turpie & Clark 2007). The nursery function of the Uilkraals Estuary is considered to be relatively important, in that some marine species caught in the surrounding marine fisheries are dependent on estuaries as nursery areas. With high macrophyte diversity and a large area of submerged macrophytes within the estuary, nursery areas and refugia are important. However, the nursery areas may have been reduced or possibly eliminated as a result of the changes in functioning and mouth dynamics brought about by the upstream dams. As per the ichthyological survey carried out in 2006, three of the species found within the Uilkraals Estuary breed in the estuary, one species is completely dependent on the estuary for the first year of its life and five species are partially dependent on the estuary. The nursery value is derived from the amount of fish caught which fall under I, III and IV in terms of their dependence on estuaries (Table 1). Of particular importance in calculating the value is Category II species for which management of estuaries plays a crucial role in inshore fisheries. Turpie & Clark (2007) estimated the total nursery value of all the estuaries within South Africa from the Orange River to Kosi Bay to be in the order of R773 million per annum, ranging from R900 to R167 million per estuary. The majority of estuaries were estimated to have a nursery value in the range of R100 000 to R10 million per annum. The Uilkraals Estuary theoretically falls within this category (Turpie & Clark 2007), but it is unlikely that this value is realised now due to the closure of the estuary to the sea for such an extended period of time, and the reduction in freshwater flow. Uilkraals Estuary Situation Assessment 37 Anchor Environmental
4.8 Genetic resources Genetic resources are valuable in many systems, but probably least valuable in freshwater and estuarine systems, where most species are extremely widespread. There are also few species that have widespread commercial potential (e.g. for agriculture or horticulture). Nevertheless, there are endemic species, and there is a possibility that these may become useful. The Uilkraals, because of its high macrophyte abundance, is one of the more interesting systems within the area in terms of diversity. However, it is not possible to determine this value. 4.9 Tourism and recreational value The Overstrand coastline, between Rooiels and Pearly Beach which includes the Uilkraals catchment has become an increasingly popular tourist destination for South Africans and overseas tourists. Much of the appeal lies in the natural features of the area, particularly the coastline which provides opportunities for peaceful getaways or adventure holidays involving a variety of aquatic and non-aquatic outdoor activities. The area is surrounded by hills in the form of the western Franskraalberge, the central Koudeberge and range of limestone hills which merge into the coastal plains. In the scale of the Western Cape mountain ranges these are a minor attraction (van der Merwe 2008), but do contribute positively to the aesthetic attraction of the region. In addition the shifting sand dunes and limestone hills have high species endemism. There are a number of protected areas in the vicinity of the Uilkraals catchment including the Uilkraalsmond Nature Reserve, Pearly Beach, Groot Hagelkraal Nature Reserve and Quoin Point Nature Reserve. Tourism is a major economic driver in the Overstrand and its popularity as a holiday and recreational destination is on the increase. During the peak holiday seasons, the population can increase four fold. As with many estuaries in South Africa, there is an urban settlement around the mouth of the Uilkraals Estuary. The Uilenkraalsmond Holiday Resort is located directly at the mouth of the estuary and is a very popular holiday resort, generally being full during all major holiday periods (Figure 14). The holiday resort covers a large area having both cottages and a caravan park with camping facilities. At R550 per night in self catering accommodation during the peak season and R400 a night out of season, it is expected that the resort generates a relatively substantial amount, which can be ultimately attributed to the estuary. There are a couple of upmarket bed and breakfast facilities located in the Franskraal village. The main attractions of the estuary are for fishing, birdwatching, and relaxation. The Uilkraalsmond area is considered to be under increasing development pressure, with the proposed rural development in the area (van de Merwe 2008). Tourism is also an important industry in the areas in the vicinity of the Uilkraals Estuary, with a range of adventure, ecotourism and consumptive (fishing) activities available to visitors. The Uilkraals River is considered an asset amongst the five rivers listed within the Strandveld area, with the coastal features at the mouth of the Uilkraals Estuary listed as important because of the tourism value that they hold. T he area adjacent to the mouth is varied with the western section forming the rocky outstretches linking to Gansbaai and the eastern section Uilkraals Estuary Situation Assessment 38 Anchor Environmental
Page 1 and 2: C.A.P.E. Estuaries Management Progr
Page 3 and 4: ubble spanning almost two-thirds of
Page 5 and 6: estuary’s functioning is catered
Page 7 and 8: ABBREVIATIONS AND ACRONYMS WMA BAS
Page 9 and 10: The reserve determination process .
Page 11 and 12: construction of the Kraaibosch dam
Page 13 and 14: The Uilkraals catchment lies within
Page 15 and 16: The Kraaibosch dam (Figure 6) was c
Page 17 and 18: eaches and tourism and fishing indu
Page 19 and 20: 3. ECOLOGICAL CHARACTERISTICS AND F
Page 21 and 22: The first time in recorded history
Page 23 and 24: 3.2 Water chemistry The distributio
Page 25 and 26: other associated high water levels.
Page 27 and 28: 3.6 Fish Estuaries provide an extre
Page 29 and 30: Table 2. Species composition, abund
Page 31 and 32: For this study, a count of water-as
Page 33 and 34: score of 55 (van Niekerk, unpubl. d
Page 35 and 36: 4. ECOSYSTEM SERVICES 4.1 What are
Page 37: isolation, but only inasmuch as it
Page 41 and 42: 5. LEGISLATION AND MANAGEMENT ISSUE
Page 43 and 44: Land use & management Water quality
Page 45 and 46: Table 10. Provincial and local gove
Page 47 and 48: Goal # Goal Strategies practices do
Page 49 and 50: 5.4 Exploitation of living marine r
Page 51 and 52: In terms of ICMA, all land within o
Page 53 and 54: (e) stabilising walls; (f) building
Page 55 and 56: Table 14 (Overstrand Local Municipa
Page 57 and 58: Table 13. Overberg District Spatial
Page 59 and 60: Component Strategy with spatial imp
Page 61 and 62: Component Strategy with spatial imp
Page 63 and 64: Table 14. Overstrand Local Municipa
Page 65 and 66: Component Description Policies 9. S
Page 67 and 68: Issues of surrounding land use and
Page 69 and 70: protected area by a single manageme
Page 71 and 72: 6. REFERENCES Adams, J.B., Bate, G.
Page 73 and 74: Smith, N & Cullinan, C. 2000. Revie
Page 75 and 76: 8. Plan for awareness-raising and p

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