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Location South Africa, Western Cape
Central coordinates 18o 28.00' East  32o 23.00' South
IBA criteria A4i
Area 1,700 ha
Altitude 0 - 343m
Year of IBA assessment 2001

BirdLife South Africa



Summary Verlorenvlei is a closed coastal estuarine-lake and marsh system fed by an intermittent allogenic river. The estuary mouth lies along the Atlantic Ocean. Verlorenvlei is one of the largest natural wetlands along southern Africa's west coast, and it is one of the few coastal freshwater lakes in South Africa. The wetland regularly supports over 5 000 birds and occasionally it holds over 20 000, including over a thousand waders of at least 11 different species.

Site description Verlorenvlei is an estuary, fed by an intermittently flowing river, on the Atlantic Ocean, 3 km east of Elands Bay and 25 km south of Lambert’s Bay. It is connected to the sea via a shallow, narrow, 2.5-km-long channel, but a rocky sand-covered bar at the mouth and other artificial obstructions make Verlorenvlei a virtually closed system. Because of its intermittent connection with the ocean, Verlorenvlei can be regarded as a coastal lake and reed-swamp system. It is one of the largest natural wetlands along southern Africa’s west coast, and it is one of the few coastal freshwater lakes in South Africa.The lake is located north of a ridge of rugged hills with high krantzes near the sea. The main body of the lake is approximately 13.5 × 1.4 km, with an average depth of c.3 m and a maximum depth of c.4.5 m during the wet season. During winter the lake fills and overflows into the sea near Eland’s Bay, but during summer it gradually desiccates, reaching its lowest levels at the end of the dry season.

Large masses of filamentous green algae are common in the channel, where the water is often stagnant and hyper-saline. The vlei is dominated by aquatic vegetation, including Myriophyllum which, at times, occupies large areas, e.g. in the upper reaches below reedbeds. Marsh vegetation of Typha, Phragmites, Cyperus and Juncus is common and widespread on the fringes of the lake. The terrestrial vegetation surrounding the vlei is transitional between karroid and fynbos vegetation, resulting in a high diversity of ecotonal communities.

Key Biodiversity See Box for key species. Verlorenvlei supports over 189 bird species, of which 75 are waterbirds. The wetland regularly supports over 5,000 birds and occasionally it holds over 20,000, including more than 1,000 waders of at least 11 different species. Most importantly, the area is a moulting ground and summer refuge for ducks (Anatidae), and it regularly supports extremely large numbers of Anas undulata, A. smithii and Tadorna cana. Large numbers of Podiceps cristatus, Fulica cristata, Larus hartlaubii and Phalacrocorax carbo are also supported. There is a high density of Circus ranivorus, which forage over the marsh and reedbank areas. Haematopus moquini and Charadrius pallidus are recorded at the estuary mouth from time to time. The palustrine habitats are diverse and rich and hold populations of secretive rails (Rallidae), including large numbers of Sarothrura rufa, Rallus caerulescens and Porzana pusilla. The diverse ecotonal terrestrial vegetation around Verlorenvlei’s fringes supports several restricted-range and/or biome-restricted species, including the recently described Certhilauda curvirostris (see account for IBA ZA023).

Non-bird biodiversity: Rare plants include Ferraria foliosa, F. densepunctulata, Cerycium venoum (presumed extinct) and Cullumia floccosa. The fish Barbus burgi (CR) has a global range restricted to the Verlorenvlei system and some of the upper catchment streams of the Berg river. Among reptiles, the IBA lies in the centre of the ranges of several Namaqualand endemics, most of which have been recorded in the vicinity and may be present in the succulent Karoo terrestrial vegetation surrounding the wetland: Homopus signatus, Bitis schneideri (VU), B. cornuta, Acontias litoralis, Typhlosaurus caecus, Scelotes sexlineatus, Meroles knoxii, Cordylus cataphractus (VU), C. macropholis, Gerrhosaurus typicus (LR/nt), Bradypodion occidentale and Pachydactylus austeni.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
South African Shelduck Tadorna cana winter  288-470 individuals  A4i  Least Concern 
Cape Shoveler Spatula smithii winter  103-600 individuals  A4i  Least Concern 
Great Crested Grebe Podiceps cristatus resident  5-20 breeding pairs  A4i  Least Concern 
Great Crested Grebe Podiceps cristatus winter  87-123 individuals  A4i  Least Concern 
Pied Avocet Recurvirostra avosetta non-breeding  78-452 individuals  A4i  Least Concern 
Hartlaub's Gull Larus hartlaubii winter  209-377 individuals  A4i  Least Concern 

IBA Monitoring

2012 high not assessed low
unset
Medium - based upon reliable but incomplete / partially representative data

Agriculture and aquaculture annual & perennial non-timber crops - agro-industry farming happening now some of area/population (10-49%) moderate to rapid deterioration high
Agriculture and aquaculture annual & perennial non-timber crops - shifting agriculture happening now small area/few individuals (<10%) slow but significant deterioration low
Agriculture and aquaculture annual & perennial non-timber crops - small-holder farming likely in long term (beyond 4 years) small area/few individuals (<10%) slow but significant deterioration low
Agriculture and aquaculture livestock farming and ranching (includes forest grazing) - nomadic grazing happening now some of area/population (10-49%) slow but significant deterioration medium
Agriculture and aquaculture livestock farming and ranching (includes forest grazing) - small-holder grazing, ranching or farming happening now some of area/population (10-49%) moderate to rapid deterioration high
Biological resource use fishing & harvesting aquatic resources - unintentional effects: subsistence/small scale happening now some of area/population (10-49%) moderate to rapid deterioration high
Biological resource use gathering terrestrial plants - unintentional effects (species being assessed is not the target) likely in short term (within 4 years) majority/most of area/population (50-90%) moderate to rapid deterioration high
Climate change and severe weather drought happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Climate change and severe weather habitat shifting and alteration likely in short term (within 4 years) some of area/population (10-49%) slow but significant deterioration medium
Energy production and mining renewable energy likely in long term (beyond 4 years) some of area/population (10-49%) slow but significant deterioration medium
Human intrusions and disturbance recreational activities likely in short term (within 4 years) majority/most of area/population (50-90%) moderate to rapid deterioration high
Human intrusions and disturbance work and other activities likely in long term (beyond 4 years) small area/few individuals (<10%) slow but significant deterioration low
Invasive & other problematic species, genes & diseases invasive non-native/alien species/diseases - named species likely in short term (within 4 years) some of area/population (10-49%) moderate to rapid deterioration medium
Natural system modifications fire & fire suppression - increase in fire frequency/intensity happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Natural system modifications other ecosystem modifications happening now some of area/population (10-49%) slow but significant deterioration medium
Pollution agricultural & forestry effluents - herbicides and pesticides happening now some of area/population (10-49%) slow but significant deterioration medium
Pollution agricultural & forestry effluents - nutrient loads happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Pollution domestic & urban waste water - type unknown/unrecorded likely in short term (within 4 years) some of area/population (10-49%) slow but significant deterioration medium
Pollution excess energy - light pollution happening now some of area/population (10-49%) slow but significant deterioration medium
Pollution excess energy - noise pollution happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Pollution garbage & solid waste likely in short term (within 4 years) some of area/population (10-49%) slow but significant deterioration medium
Residential and commercial development commercial and industrial development likely in short term (within 4 years) small area/few individuals (<10%) moderate to rapid deterioration low
Residential and commercial development housing and urban areas happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Residential and commercial development tourism and recreation areas happening now majority/most of area/population (50-90%) slow but significant deterioration high
Transportation and service corridors flight paths happening now small area/few individuals (<10%) no or imperceptible deterioration low
Transportation and service corridors roads and railroads happening now some of area/population (10-49%) moderate to rapid deterioration high
Transportation and service corridors utility & service lines happening now some of area/population (10-49%) moderate to rapid deterioration high

Shrubland Shrubland - Cape (fynbos)  0 0 poor (40-69%) poor (40-69%) very unfavourable
Wetlands (inland) Estuarine waters  0 0 moderate (70-90%) poor (40-69%) very unfavourable
Wetlands (inland) Saline lakes  0 0 moderate (70-90%) poor (40-69%) very unfavourable

Alopochen aegyptiaca Egyptian Goose 2014 2014 individuals 100 favourable
Tadorna cana South African Shelduck 470 489 individuals 100 favourable
Spatula smithii Cape Shoveler 600 615 individuals 100 favourable
Podiceps cristatus Great Crested Grebe 123 140 individuals 100 favourable
Pelecanus onocrotalus Great White Pelican 478 478 individuals 100 favourable
Circus ranivorus African Marsh-harrier 30 9 individuals 30 very unfavourable
Recurvirostra avosetta Pied Avocet 452 1256 individuals 100 favourable
Larus hartlaubii Hartlaub's Gull 377 377 individuals 100 favourable
Hydroprogne caspia Caspian Tern 31 34 individuals 100 favourable

Some of site covered (10-49%)  A comprehensive and appropriate management plan exists that aims to maintain or improve the populations of qualifying bird species  Some limited conservation initiatives are in place  low 

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Verlorenvlei Wetlands of International Importance (Ramsar) 1,500 protected area contained by site 1,500  

Local conservation groups The local conservation group below is working to support conservation at this IBA.

Name Year formed
Elands Bay environmental group. 0

Habitats

IUCN habitat Habitat detail Extent (% of site)
Wetlands (inland) Estuarine waters; Saline lakes  -
Shrubland Shrubland - Cape (fynbos)  -

Land use

Land-use Extent (% of site)
agriculture -
tourism/recreation -

References Baxter and Davies (1994), Cooper et al. (1976), Cowan (1995), Cowan and Marneweck (1996), Grindley and Grindley (1987), Sinclair et al. (1986), Summers et al. (1977), Taylor (1997a,b), Underhill and Cooper (1984).

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Recommended citation  BirdLife International (2015) Important Bird Areas factsheet: Verlorenvlei Estuary. Downloaded from http://www.birdlife.org on 02/06/2015

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