5.4.2 Anas platyrhynchos (Mallards)
Mallards have been introduced around the world as domestic and sporting birds
(Champagnon et al. 2013; Long 1981). The first individuals sighted in the wild in
South Africa were around 1980 in Gauteng and the Western Cape, and are presumed
to be escapees from private collections. In South Africa, Mallards are reported to
hybridise with the Yellow-billed Duck, A. undulata (Dean 2000), and this formed
the basis for the listing of this species in the Regulations as Category 2b and
therefore the need for control (van Wilgen and Wilson 2018; Davies et al. 2020,
Chap. 22), and an impact of Major due to hybridisation with other species in the
genus Anas (Evans et al. 2016). A genetic study, using microsatellite markers of
Mallards, Yellow-billed Ducks and putative hybrids, demonstrated that hybridisation
is indeed taking place, but that the direction of hybridisation is into the Mallard
population, most commonly with Mallard females and Yellow-billed Duck males
(Stephens et al. 2020). This suggests that national control of mallard ducks may be
necessary to effectively protect the genetic integrity of Yellow-billed Ducks.
5.4.3 Passer domesticus indicus (House Sparrows)
House sparrows are believed to have been introduced to South Africa from India by
sugar cane workers who brought them as pets. They have expanded their range
considerably since the 1950s when they were mainly confined to KwaZulu-Natal,
and the population has expanded across South Africa and into all neighbouring
countries in southern Africa. House Sparrows are an example of an opportunist,
commensal species. In Pietermaritzburg, House Sparrow density was found to be
positively related to heavily transformed land use types, such as shopping malls
(Magudu and Downs 2015). As they appear not to impact on native birds, and are
not predators, this species is listed in the Regulations as Category 3, and is considered to have a moderate impact due to competition with other small passerines
(Evans et al. 2016).
5.4.4 Fringilla coelebs (Chaffinch)
Chaffinches originate in Europe, western Asia and North Africa but were introduced
to Cape Town in the 1890s by C J Rhodes as part of his attempt to make the Cape
more like his homeland. Currently, this species is most commonly seen on the Cape
Peninsula, although birds have been seen as far as Somerset West. Given the
130 years of establishment, it seems unlikely that this species will spread. This
species is not listed as invasive under South African legislation, and its impact has
not been assessed due to a deficiency of data (Evans et al. 2016).
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Mallards have been introduced around the world as domestic and sporting birds
(Champagnon et al. 2013; Long 1981). The first individuals sighted in the wild in
South Africa were around 1980 in Gauteng and the Western Cape, and are presumed
to be escapees from private collections. In South Africa, Mallards are reported to
hybridise with the Yellow-billed Duck, A. undulata (Dean 2000), and this formed
the basis for the listing of this species in the Regulations as Category 2b and
therefore the need for control (van Wilgen and Wilson 2018; Davies et al. 2020,
Chap. 22), and an impact of Major due to hybridisation with other species in the
genus Anas (Evans et al. 2016). A genetic study, using microsatellite markers of
Mallards, Yellow-billed Ducks and putative hybrids, demonstrated that hybridisation
is indeed taking place, but that the direction of hybridisation is into the Mallard
population, most commonly with Mallard females and Yellow-billed Duck males
(Stephens et al. 2020). This suggests that national control of mallard ducks may be
necessary to effectively protect the genetic integrity of Yellow-billed Ducks.
5.4.3 Passer domesticus indicus (House Sparrows)
House sparrows are believed to have been introduced to South Africa from India by
sugar cane workers who brought them as pets. They have expanded their range
considerably since the 1950s when they were mainly confined to KwaZulu-Natal,
and the population has expanded across South Africa and into all neighbouring
countries in southern Africa. House Sparrows are an example of an opportunist,
commensal species. In Pietermaritzburg, House Sparrow density was found to be
positively related to heavily transformed land use types, such as shopping malls
(Magudu and Downs 2015). As they appear not to impact on native birds, and are
not predators, this species is listed in the Regulations as Category 3, and is considered to have a moderate impact due to competition with other small passerines
(Evans et al. 2016).
5.4.4 Fringilla coelebs (Chaffinch)
Chaffinches originate in Europe, western Asia and North Africa but were introduced
to Cape Town in the 1890s by C J Rhodes as part of his attempt to make the Cape
more like his homeland. Currently, this species is most commonly seen on the Cape
Peninsula, although birds have been seen as far as Somerset West. Given the
130 years of establishment, it seems unlikely that this species will spread. This
species is not listed as invasive under South African legislation, and its impact has
not been assessed due to a deficiency of data (Evans et al. 2016).
130
J. Measey et al.