Wetland Park welcomes rains
White pelicans at St Lucia
Dave Savides
Although the drought in the region remains severe, the state of the St Lucia Estuary remains healthy.
This despite seawater flowing into the lake system for 175 days after the mouth breached in March following a combination of high seas caused by Cyclone Gamede, strong onshore winds and exceptionally high tides.
The mouth has since closed naturally (45 days ago) preventing more sea water from entering the system.
According to authorities, salinity is fairly stable at 36ppt (36 grams of salt per litre of water) from March to date.
'Water levels have dropped by an estimated 12cm as a result of evaporation,' said Wetland Park Authority media spokesperson - Pontso Pakkies.
'Due to drought and a shortage of rainfall the flow of fresh water into the system from the catchments has been minimal over the last few months.
'This week's downpours have been a bonus, because historical records show that when salinity rises above 55 ppt then the system starts to be stressed.
'Wetland Park management will continue to monitor the ecosystems, especially the salinity of Lake St Lucia and availability of fresh water for game.'
Bird counts in the Wetland Park are regularly undertaken by staff in order to detect changes in waterbird population and wetland conditions.
Bird numbers
'The annual winter water bird count covered 31 wetlands in and adjacent to the Park,' said Pakkies.
'They are part of the winter 2007 African Waterfowl Census whose objectives are to monitor the waterbird populations throughout Africa.
'Due to the drought, six pans are totally dry and five others are in the process of drying up.
'In total, 21 000 birds were counted in this survey across the Wetland Park and adjacent wetlands.
'Of these over 15 088 were counted in the Lake St Lucia Estuary with waders making up the majority at 25% followed by flamingoes at 18% and ducks.
'Also noted during the count was the abundance of white-breasted cormorants at Lake Sibaya, White-fronted Plovers along the seashore between Cape Vidal and Sodwana shoreline with 427 birds being counted on the 72 km beach.
'African Spoonbills, Egyptian Goose, Little Grebe (dabchick), Greenbacked Heron, Hadeda Ibis and African Pied Wagtail, African Fish Eagle, African Jacana and Pied Kingfisher were also spotted.'
Results from the bird count
• Waders (including avocet & stilt) - 5 373
• Ducks - 2 471
• Flamingo - 3 996
• Pelicans - 2 897
• Cormorants - 1 644
• Herons and egrets - 1 779
• Gulls and terns - 1 104
• Storks, ibis & spoonbills -
1 571
• Fish eagle - 27
• Other fishfeeders - 145
• Other birds - 468
TOTAL - 21 475
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