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Flora |
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1978
(Ref.1): "The
mangrove community of the Beachwood nature reserve, is the only
feature of real botanical significance which remains around the Mgeni
estuary. This is largely
as a result of urban encroachment in the form of recreational
facilities on the southern bank.
A fair proportion of the reserve itself is a shooting range.
The islands in the center of the Mgeni estuary are as yet
undeveloped". |
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Halophytes |
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1978
(Ref.1): "Of
the 50 ha set aside as the Beachwood nature reserve, 12,14 ha are
undermangroves. The two
common species are the White (Avicennia) and Black (Bruguiera)
mangrove. Transplantation
of specimens of the Red (Rhizophora) mangrove from Durban Bay and
Ceriops from Kosi Bay have been made.
The introduction of Lumnitzera is envisaged. The fresh water
mangrove (Barringtonia) has also been introduced into the reserve.
Amongst the mangrove community, are various salt tolerant
species of grasses, reeds and rushes.
The plant community as a whole supports a very characteristic
and interesting estuarine adapted fauna, dependent on the rich supply
of organic detritus which the swamp provides.
Because of the educational value of this area (by virtue of its
proximity to the main centers of education in Natal) it has been set
as a nature reserve, to protect the area from the pressures which
formerly threatened it (such as reclamation, “Disneyland”
development, uncontrolled public access, sand removal, etc.).The Natal
Parks Board, presently in control of the area, are restoring the
swamp. This involves
among other things, the constuction of gabions, dune stabilization,
fencing, dredging and debris removal.
Other suggestions have included the building of a weir which
could be closed when necessary to exclude the Mgeni should it be
polluted, excessively silt laden or in some other way a threat to the
nursery function of the reserve.
The use of high pressure hoses to wash away sand which has
accumulated amongst the root masses of the mangroves has also been
suggested." |
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Algae |
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Aquatic
Vegetation |
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1978
(Ref.1):
"Aquatic flora species spotted in the estuarine area of the
Mgeni, are sea-lettuce (Ulva), during winter.
Water hyacinth (Eichornia) and eelgrass (Vallisneria).Conditions
are reported as too turbid for the development of Zostera and Ruppia,
however blooms of sea-lettuce (a large marine alga named Ulva) have
been reported in winter. Water
hyacinth (Eichornia) has been reported amongst the mangroves in the
past, and in the extreme north of the reserve, water conditions are
sufficiently fresh for Vallisneria (eelgrass) and Savinia (Kariba
weed) to develop." |
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Semi-aquatic
Vegetation |
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Terrestrial
vegetation |
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1978
(Ref.1): "
The
most significant botanical feature of the Mgeni estuary is the
Mangroves in the Beachwood nature reserve.
The 2 most common mangrove species are the White mangroves
(Avicennia) and the Black mangroves (Bruguiera) amongst which there
are various salt tolerant grass, reed and rush species." |
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Fauna |
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Zooplankton |
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1978
(Ref.1): "Studies
of the zooplankton of the lower
reaches of Beachwood concluded that conditions in the creek did
not favour the survival of estuarine and marine forms of zooplankton.
Fresh water forms of zooplankton were dominant.
Crab, fish and prawn larvae were the most abundant meroplankton
forms" |
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Benthos |
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1978
(Ref.1): "In
1972, 16 species of benthic animals were found to be present in the
estuary, dominated by the polychaetes Ceratonereis and Desdemona (both
being tolerant of low oxygen conditions). The lack of amphipods, isopods and tanaids was considered to
be striking, since these forms normally comprise a considerable part
of the biomass in Natal’s estuaries.
This is because they are probably less tolerant of pollution. Production was limited to the top two centimeters of
sediment, below which the sediment was anaerobic.
At the head of the estuary, some oligochaetes and entomostraca
(Pseudodiaptomus and Cyclops) occur, indicating the influence of fresh
water. Attention has been given to the
distribution and occurrence of fiddler (four species of Uca) and
gastropod mollusks, in Beachwood swamp.
In 1964 Brown found 10 species of gastropods (out of the 13
species listed as occurring in South African mangroves) present.
This represented the richest assemblage known at any one
locality. The greatest densities were 370/sq
metre. Brown concluded that the area might support populations
ranging from 200 000 Cassidula to 8 million Assiminea.
Beachwood is the type locality for Neritina natalensis.
Gastropod densities varied according to texture and moisture
content of the substrate as well as the amount of shade.
The same sort of factors govern the distribution of fiddler
crabs. The mangrove whelk
(Terebralia) has since been introduced from Durban Bay" |
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Epifauna |
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1978
(Ref.1): "In
the estuary, animal communities of the marginal vegetation were poorly
developed. Thirteen
species typical of estuarine conditions were found, these being
markedly different in May (when fresh water influenced) and in August
(when more typical of brack water forms).
Above the estuary the fauna of the marginal vegetation is
slightly better developed, with 18 species listed as present 2,5 km
above the estuary in 1965. Of the larger crustacea in the Beachwood
swamp, shrimps (Caridina) are said to be dominant, particularly in
spring when thousands of juveniles are said to be present.
Two species of prawns occur in the estuary, but they are not
common" |
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Aquatic
Invertebrates |
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Insects |
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Fish |
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1978
(Ref.1): "
30
Species of fish (mainly mullet and “glassies” species) have been
reported in the Mgeni estuary. 5 Species of fish are reported to breed
in the estuary and the marine species, tigerfish, stumpnose and perch
occur there as well. Amongst the fresh water fish species are
“guppies”and mud bream. "Of
the 30 species of fish reported as present in the Beachwood creek a
striking proportion belong to the gobioid family.
Mullet, followed by “glassies” (Ambassis) are the dominant
species, the ratio of juvenile mullet to all other species being in
excess of 20:1. Juveniles
1,5 cm in length representing fish only a few weeks old, have been
caught after coming into the estuary from the sea.
The Beachwood population of Periophthalmus (the mudskipper) is
one of the most southerly in terms of its distribution. Five species of fish are reported to breed in the estuary"
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Amphibians
and Reptiles |
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Birds |
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1978
(Ref.1): "
71
bird species have been reported from around the Mgeni estuary at the
Beachwood reserve". |
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1978
(Ref.1): "The
Mgeni sandbar is an important roost for
terns and gulls, in particular for the White-winged black
terns. There have reports of 23 wader species, of which Sanderling,
Common and Curlew sandpipers are the most common.
A rare bird that of the area is the Crab plover.
Fish eating birds, such as cormorants, herons and egrets are
common." |
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Mammals |
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1978
(Ref.1): "Among
the other fauna that have been reported, were vervet monkeys, grey
duiker, banded mongoose, leguaans, lizards, geckoes, skinks, snakes,
frogs, toads and insects."
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