Prior to 1950 records indicated that the estuary only closed on one occasion
during the long and sustained drought in the 1930's.
No 'closed mouth' record seemed to exist prior to or after this date (1930's)
until 1950 when a dramatic change was effected in the management of the surrounding
drainage in the Monzi Flats. Prior to 1950 the Monzi Flats had operated as
a filtering system to remove silt from the Umfolozi Flood waters, which entered
the St. Lucia Estuary at Honeymoon Bend.
With the growth in the sugar industry preference was given to sugar cane rather
than the vitally important de-silted Monzi Flats water flowing into the St.Lucia
Estuary.
Prior to 1950 the Umfolozi River split into hundreds of tiny channels of very
slow flowing water, and the reeds in these slow flowing channels trapped and
removed the silt. By the time the Umfolozi water reached the St Lucia Estuary
a fairly large proportion of the silt had been removed.
The new Unmfolozi canal then dumped unfiltered water into the St. Lucia Estuary.
Immediately this situation became a problem and the huge silt load in the
Umfolozi water started to deposit silt and sand in the slower moving estuary
waters.
The St Lucia estuary mouth was rapidly silted-up.
A costly dredging operation was started, but proved ineffective. So, the next
plan of action after years of dredging the estuary mouth area, was to prevent
the Umfolozi River from entering the St Lucia estuary.
The Umfolozi River was then canalised straight out to sea at Mpalane, a coastal
resort just south of the St Lucia River mouth. The impact of this decision
is still felt today. Often this silt plume from the Umfolozi River is blown
by strong south winds as far as Sodwana Bay.
Cape Vidal is also in jeopardy affecting the coral reefs and the good snorkelling
generally experienced in this area. But the greatest impact has been noted
on the St. Lucia Estuary and the lake area as well.
Prior
to 1950 records indicated that the estuary only closed on one occasion during
the long and sustained drought in the 1930's.
No 'closed mouth' record seemed to exist prior to or after this date (1930's)
until 1950 when a dramatic change was effected in the management of the
surrounding drainage in the Monzi Flats. Prior to 1950 the Monzi Flats had
operated as a filtering system to remove silt from the Umfolozi Flood waters,
which entered the St. Lucia Estuary at Honeymoon Bend.
With the growth in the sugar industry preference was given to sugar cane
rather than the vitally important de-silted Monzi Flats water flowing into
the St.Lucia Estuary.
Prior to 1950 the Umfolozi River split into hundreds of tiny channels of
very slow flowing water, and the reeds in these slow flowing channels trapped
and removed the silt. By the time the Umfolozi water reached the St Lucia
Estuary a fairly large proportion of the silt had been removed.
The new Unmfolozi canal then dumped unfiltered water into the St. Lucia
Estuary. Immediately this situation became a problem and the huge silt load
in the Umfolozi water started to deposit silt and sand in the slower moving
estuary waters.
The St Lucia estuary mouth was rapidly silted-up.
A costly dredging operation was started, but proved ineffective. So, the
next plan of action after years of dredging the estuary mouth area, was
to prevent the Umfolozi River from entering the St Lucia estuary.
The Umfolozi River was then canalised straight out to sea at Mpalane, a
coastal resort just south of the St Lucia River mouth. The impact of this
decision is still felt today. Often this silt plume from the Umfolozi River
is blown by strong south winds as far as Sodwana Bay.
Cape Vidal is also in jeopardy affecting the coral reefs and the good snorkelling
generally experienced in this area. But the greatest impact has been noted
on the St. Lucia Estuary and the lake area as well.
Why is it essential to keep an estuary mouth open? To a large extent it is
about the euryhaline fish and invertebrates, mangrove swamps and oyster beds.
The fish are mainly the spotted grunter, cob or kabeljou, river bream and
various mullet species.
It is estimated that over a hundred different species of fish utilise the
St Lucia estuary as a nursery, but use the sea as the maternity ward or spawning
area.
A closed estuary mouth prevents fish from gaining access to the maternity
ward in order to spawn. The annual spawning run takes place from April to
August.
Every year the central East Coast of South Africa experiences an annual sardine
run the fish congregating in the Port St. Johns off-shore marine area in early
June.
These enormous shoals then move slowly north feeding on the huge blooms of
plankton that form in the winter months.
It is presumed that once the fish from St. Lucia have spawned, the young larval
fish drift south to meet with the plankton bloom just south of St Lucia mainly
between Ballito and Port St. Johns. These larval fish, prawns and crab then
feed on the plankton and grow rapidly.
They eventually drift with currents that take them in a huge circular trip
out into the Eastern Indian Ocean and finally back past Madagascar and to
St Lucia.
Research indicates that these larval fish and invertebrates arrive at St.
Lucia between August and November each year.
The Great Lake of St. Lucia was declared a game reserve on the 27 April 1897.
The conserved area was the 35 000 hectare lake and a one km strip of land
surrounding the lake. Later, various other conservation areas were added.
Most recently, the Lake and the adjacent coastal areas were declared a World
Heritage Site by UNESCO protocol on 1 December 1999.
This 328 000 hectare reserve was South Africa’s first Natural World
Heritage Site and it encompassed five major eco-systems. The ecological status
of the lake responds significantly to the influx of freshwater. During periods
of low rainfall, the salinity rises bringing on a whole different ecosystem.
The saline phase of the Lake will be examined and the occurrence of two interesting
bird species.
During the saline phase of the lake, larger than normal numbers of Pelicans
and flamingos gather in the lake.
These birds currently are being seen in fairly large numbers. A visit to the
view site en route to Mission Rocks will enable you to see flocks of these
birds on the lake.
Pelican flock when the birds drive fish into tight shoal and then scoop them
up for consumption.
High pelican numbers occur as the salinity reaches that of seawater.
When the salinity rises even further, Flamingos arrive to feed on the unicellular
algae and invertebrates that starts to proliferate, in the absence of certain
fish species.
Flamingo’s are filter feeders, although there are a variety of other
filter feeding birds, flamingos are highly specialized to exact microscopic
alga and invertebrates from the saline waters of Lake St. Lucia.
A distinguishing feature of the Flamingoes is that they feed with their heads
upside down. The tongue acts as a pump, drawing water in the slightly open
beak then forcing it through a band of hair like structures (birds do not
have hair), which filter out the tiny particles of food.
There are two species of Flamingos, the lesser Flamingo filters mainly surface
food comprising of microscopic algae and diatoms, whereas the Greater Flamingo
feeds near the bottom and will often submerge their whole head. They feed
on larger sized food like crustaceans, molluscs and diptera larvae.
Investment interest in the Park has grown in the last few months. The international and domestic hospitality industries are focusing increasingly on the development of new destinations to augment the tried and tested despite global events such as the Iraq war. Requests for proposals have been issued for the first 10 investment opportunities in the Park. The next few months promise to be busy as bidders prepare their submissions.
The Mabibi development got the green light from the Authority late last year. The 12 bed lodge will be proceeding to construction. The agreement with the concessionaire also includes the upgrade and management of the public camp site and day visitor facility. Communities in the area look forward to the opening of the lodge doors after a long and arduous wait.
Siyabonga centre was completed in May 2003. Interest has been shown by property managers in the administration of the centre which will boast a craft outlet, tourism information centre, office space and some retail space. A call for proposals will be issued by the Authority in respect of these opportunities.