Johannesburg’s environment has
changed substantially from a Moist Highveld Grassland Biome into an ‘Urban
Forest’ made up of roughly ten million trees.[1] To
get an idea of what the terrain in Johannesburg must have looked like in the
past one could look at the Melville Koppies Nature Reserve in Central
Johannesburg and Klipriviersberg Nature Reserve in the South of Johannesburg. The
rapid urbanisation of the Johannesburg Area: through development of pristine
grassland and the draining of wetland areas into office parks, strip malls,
housing complexes and the urban sprawl and associated human activities has led
to a high number of local extinctions.
Humans are destructive, but human
activity has led to certain environmental conditions that have opened up spaces
for the proliferation of a few species that are able to find a place for
themselves in our rapidly changing urban environments. In Johannesburg, the
creation of an urban forest has enabled a few opportunistic animals a chance to
establish themselves in a new environment free from established competition and
to a large degree, predators.[2]
Some of these are new arrivals from other regions and others have always been
here but have become more common due to some ecological factor or another. Birds
are among the most successful of these animals and are for many people living
in the urban forest that is Johannesburg the only real source of wildlife they
may encounter.
Traditionally there are certain
types of birds that are associated with humans. These include the cosmopolitan
city bird, the Rock Dove or Feral Pigeon (Columba
livia). This is an introduced species and is abundant even in the most
densely populated areas in Johannesburg. There are another two pigeons in the
area, although not as common as the Feral Pigeon, that have become well
established in the urban environment, these are the Rock or Speckled Pigeon (Columba guinea) and the African Olive or
Rameron Pigeon (Columba arquatrix).
In nature the Speckled Pigeon favours roosting on cliffs, large boulders and
even caves, in Johannesburg it can commonly be found roosting on buildings in
suburbs and urban areas. This pigeon is very striking with its brick red
colouration and quite undisturbed by people. The African Olive Pigeon is a
forest species and was not always a bird of the Johannesburg area. In some
areas populations are suffering due to deforestation, but in Johannesburg their
numbers are steadily increasing. These pigeons are fruit eaters and are significant
distributors of seed and they play an important role in the urban forest. Another
bird that has a long association with humans is the House Sparrow (Passer domesticus). This bird, like the
Feral Pigeon is an introduced species from Europe. It was first introduced to
Durban in the late 1800s and there were separate introductions to East London
and Maputo. It became established in Johannesburg by 1949.[3]
Even though the House Sparrow is non-native it is not a threat to native
species, unlike another introduced species: the infamous Indian or Common Mynah
(Acridotheres tristis). This species
was introduced to Durban in the early 1900s from India, central and southern
Asia and were first introduced in Johannesburg in 1938.[4] They
are now locally abundant. These birds are aggressive, bold and intelligent and
they are undisturbed by traffic and people. They seem to have displaced local
species, like the Pied Starling (Spreo
bicolor), but field observations have shown a recent trend toward an
increase in indigenous starlings in the Johannesburg area.[5]
 |
| African Olive Pigeon |
Another
introduced species in Johannesburg is the Rose-ringed Parakeet, the population
seems to have originated from aviary escapes. These green birds are the only
parrot species that occur in the greater Johannesburg region and can often be
seen in the more forested areas, their green colour and long tails make them
unmistakable. They are very noisy birds and highly gregarious.
 |
| Rose-ringed Parakeet |
In urban and suburban areas, where
there are gardens, there are lawns. Lawns are also commonly cultivated on the
verges of suburban streets and schools, parks, sports-fields, graveyards and
open areas in office parks and housing estates all make use of lawn. These
cultivated lawns are good habitats for small invertebrates, both on the surface
as well as below the surface. One of the most familiar birds one could find on
practically any stretch of lawn or any piece of open ground with grass is the
Hadeda Ibis (Bostrychia hagedash).
 |
| Hadeda Ibis |
These large birds are common throughout the Johannesburg region and their call
is as familiar in the suburbs as car alarms and dogs barking. Increasing lawns
as well as an increase of trees in the region for roosting has led to this
species continued success. Open lawned spaces have provided a habitat for lapwings
or plovers (Vanellus) of which there
are three species which are most often seen in Johannesburg, these are: Crowned
Lapwing (V. coronatus), Blacksmith
Lapwing (V. armatus) and the lesser
seen African Wattled Lapwing (V.
senagallus). These birds commonly mob humans and animals that stray too
close to their nests, which are built on the ground. If the mobbing does not
work and the threat becomes too close to the nest or young, one of the birds will
pretend to be injured and attempt to lure the threat away. The young plovers
are excellently camouflaged and I have seen them seem to vanish before my eyes.
All three of these species have become more common in Johannesburg due to human
land use. The Spotted Dikkop or Thick-knee (Burhinus
capensis) is another bird that is expanding its range in the suburbs. These
birds are nocturnal and can often be seen at night on suburban verges. They
look like big plovers and have long legs with which they run down their prey.
In the day they can be seen crouching or standing amongst vegetation and tend
to stare out eerily. There are two owls common in the Johannesburg region and
these birds take advantage of the bounty of rodents that are associated with
humans (Rattus rattus and Mus musculus);
these are the Barn Owl (Tito alba)
and Spotted Eagle-Owl (Bubo africanus).
Both can be heard at night in suburban areas throughout Johannesburg, the Barn
Owl has a characteristic shriek and the Spotted Eagle-Owl hoots.
The urban forest has attracted some
traditionally woodland birds that would not exist in the numbers they currently
do if it was not for the trees and the shelter and food they provide. When
growing up in the South of Johannesburg I clearly remember a period where there
were simply no Grey Louries (Corythaixoides
concolor). Before the 1970s they were rare vagrants to the Witwatersrand
area and seem to have moved into region following a major drought in 1978.[6] In the mid nineties I began to notice their appearance in
the Southern Suburbs and now they are a very common sight. These birds have
adapted well to the suburban environment.
 | |
| Burchell’s Coucal |
As the vegetation mass increases in
suburban gardens the habitat of the Burchell’s Coucal (Centropus burchellii) increases. This bird is more often heard than
seen and is well known for its bubbling call. It is a voracious predator and
eats small mammals, small birds and nestlings, insects, reptiles and
amphibians. The bird often goes undetected as it clambers through the
undergrowth searching for food. The cackling Red-billed Wood-Hoopoe (Phoeniculus purpureus), although it has always
been a bird of the area, is also becoming more and more common in the urban
forest of Johannesburg. These highly gregarious and noisy birds move from tree
to tree hunting for insects and can often be seen on thatched roofs probing for
invertebrates with their long bills.
The suburban and urban environment
attracts a large number of African Pied Crows, these can be seen patrolling just
about any area in the region and are commonly associated with human
settlements. These birds are opportunistic and intelligent, they have been
known to forage under streetlights before dawn and after sunset.[7]
There are also some other animals
that have become more prolific in the Johannesburg area and some introduced
species. These include a number of insects, mammals, fish and reptiles. Some of
these animals are introduced into the environment for some or other reason,
some are escapees, some have just turned up and some are stowaways.[8]
Others still have either always been in the area and have become more common
because of human activity. This is an area that needs more (specialist)
research.
Among reptiles, there is a species
of Terrapin from North America that has become established in ponds, vlies and
streams in Johannesburg.[9]
These used to be sold as pets and were released when they became too large for
their enclosures. There is also a species of gecko that has colonized
Johannesburg known as Moreau’s Tropical House Gecko (Hemidactylus mabouia). These geckos arrive as stowaways amongst
holiday makers’ belongings who have been at the coast. They have managed to
make use of the microhabitats that surround security lights in suburban and
urban areas, the warmth from these lights and the creatures that they attract
have enables this gecko to colonize areas that would otherwise be too cold for
them to survive.[10]
In Norwood during 2010 I found two Cape Dwarf Chameleons, one dead one and on
live specimen. I am not sure if these isolated findings qualify as an
introduced species, but I intend on looking for more in the area soon. The Cape
Dwarf Gecko is another recent colonist to suburban and urban gardens. These
geckos are active in the day and can often be seen scuttling about on tree
trunks. The Striped Skink (Trachylepis
striata) is a reptile that has always occurred in the Johannesburg but it
is managing to survive where most reptiles are regionally extinct. This species
is very common on paved areas and around houses.
Most larger
mammals are unable to coexist with humans in Johannesburg. There are some hares
that can be found in park areas, on the outskirts of the city there are
mongooses and even porcupines that occasionally venture in the suburbs. One
mammal that is managing to coexist with humans in the suburban environment is
the Rock Hyrax or Dassie (Procavia
capensis). In June 2012 Municipal spokesperson Nthatisi Modingoane declared
that the Dassie population is “way above the carrying capacity of the municipal
nature reserves and other natural open spaces within the city”.[11]
Something interesting I have observed about the Hyraxs is that they are
traditionally regarded as a diurnal species, but I have observed them at night
and often hear their cries late into the night. This makes me think that
perhaps they are changing their behaviour due to human pressures and are
foraging at night.
Some
animals appear out of nowhere. During April 2012 there was a sighting of a
Baboon (Papio ursinus) in the
Klipriviersberg Nature Reserve. The Baboon was later spotted in Bassonia and
Meyersdal and has since disappeared.
The
Parktown Prawn (Libanasidus vittatus)
is the final creature that will be described here. Irrationally feared in
Johannesburg and subject of many urban myths, from exaggerations about the
impossibility of killing them, to stories about how they are the result of
science experiments gone wrong. This large insect is common in the well-wooded
suburbs of Johannesburg. They are carnivorous and spend most of their time
underground and their biology is not very well understood. The males have
spectacular heads with what appear to be tusks. There is some speculation as to
how they came to be so prolific in Johannesburg. They were not reported before
1960 and then suddenly they became highly prominent, the species has been
becoming more and more widespread in the region.[12] “The
natural habitat for this genus is in and around forests in Mpumalanga, Northern
Province and probably also Zimbabwe. During the day they can be found in
burrows or under logs. Specimens have also been collected in gardens in
Johannesburg, Randburg and Pretoria”.[13]
This overview of prolific animal
species in Johannesburg is by no means complete. I see this overview as the first
step towards further research in suburban and urban ecology in Johannesburg.
[1] Davie, L. 2004. Jozi's urban forest now at 10m trees, and growing. [Online] Available:
http://www.joburgnews.co.za/2004/sep/sep8_forest.stm [17 September 2012].
[2] Domestic cats are the main
predators of the urban environment and manage to kill a lot of the slower birds
that feed on the ground and smaller mammals and reptiles.
[3] Hockey, P.A.R, Dean W.R.J,
Ryan, P.J. (eds). 2005. Roberts – Birds
of Southern Africa, VII ed. The Trustees of the John Voelcker Bird Fund,
Cape Town. (Page 1083)
[4] Hockey, P.A.R, Dean W.R.J,
Ryan, P.J. (eds). 2005. Roberts – Birds
of Southern Africa, VII ed. The Trustees of the John Voelcker Bird Fund, Cape
Town. (Page 972)
[5] This is based on personal
observation. The indigenous starlings I am referring to here are: the Pied
Starling mentioned in the text, the Cape Glossy Starling (Lamprotornis nitens) and to a lesser extent the Red-winged Starling
(Onychagnathus morio).
[6] Hockey, P.A.R, Dean W.R.J,
Ryan, P.J. (eds). 2005. Roberts – Birds
of Southern Africa, VII ed. The Trustees of the John Voelcker Bird Fund,
Cape Town. (Page 250)
[7] Hockey, P.A.R, Dean W.R.J,
Ryan, P.J. (eds). 2005. Roberts – Birds
of Southern Africa, VII ed. The Trustees of the John Voelcker Bird Fund,
Cape Town. (Page 723)
[8] There was recently an
incident at Monte Casino where a Black Mamba (Dendroaspis polylepsis) was seen via cctv surveillance emerging
from the bonnet of a car that was parked. The snake was caught and positively
identified as a Black Mamba which is not a snake that occurs in Johannesburg.
At least another two suspected stowaway Black Mambas have been caught in
Johannesburg by reptile removal people.
[9] Branch, B. 1998. Field Guide to Snakes and other Reptiles of
Southern Africa. Struik Publishers, Cape Town. (Page 36)
[10] Alexander, G, and Marais,
J. 2007. A Guide to the Reptiles of
Southern Africa. Struik Publishers, Cape Town. (Page 300)
[11] Modingoane said the City
had received a barrage of complaints from residents in Fourways Gardens,
Norscot and Lonehill in the north, and Glenvista, Mondeor and Klipriviersberg
in the south about damage to their properties caused by dassies… Current
indications suggest that while some of the dassies venture into residential
areas merely to forage for food, other groups have taken up permanent residence
within residential areas, sometimes in drains or roofs, or even in houses. He
explained that the growth in infrastructure had led to a loss of natural open
spaces, while land use regulations had resulted in residential properties
“encroaching on the natural habitats of some mammal species, resulting in
human-wildlife conflict.”’
waka’Ngobeni,
M. L. 2012. Dassie numbers to be
controlled. [Online] Available:
http://www.jhbcityparks.com/index.php?option=com_content&view=article&id=838:dassie-numbers-to-be-controlled&catid=1:latest&Itemid=56
[18 September 2012].
[12] “The first museum specimen
from Johannesburg was collected by R. du Preez in November 1962. It now seems
possible that they were originally present in low numbers and that
environmental changes in suburban gardens led to an increase in numbers and
range. However, urbanization may not have been the only reason for an increase
in numbers, and changes in weather patterns may also have played a role. When
the rainfall increased over the past three summers it was expected that this
would lead to a massive increase in populations, but surprisingly, the opposite
occurred. It is thought that flooding of burrows and refuges could have led to
a decline in populations. Unfortunately entomologists do not have quantitative
data associated with changes in population density, but it is possible that
this species could act as environmental indicators” Toms, R. 2003. The monstrous cricket "turns 200"
while "badboy" Parktown prawn steals the limelight.
[Online] Available: http://www.scienceinafrica.co.za/2003/november/monster.htm
[17 September 2012].
[13] Toms, R. 2003. The monstrous cricket "turns 200"
while "badboy" Parktown prawn steals the limelight.
[Online] Available: http://www.scienceinafrica.co.za/2003/november/monster.htm
[17 September 2012].
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