Blue Swallow, Hirundo atrocaerulea, populations, and as livestock trampling has
been shown to negatively affect Burrowing Owls, Athene cunicularia elsewhere
(Holmes et al. 2003), the horses may be similarly affecting the burrow-nesting
swallows. Another population is in Rooisands Nature Reserve and surrounding
properties near Kleinmond in the Western Cape. No data are available in the formal
literature on either population. Muller and Bourne (2018) report on a population of
>100 feral horses in the Steinkopf area of the Northern Cape province, and suggest
that there may be significant competition with domestic livestock in that area.
Throughout the world, feral horses cause degradation and a decline in ecological
integrity (Porfirio et al. 2017). Affects would be context-dependant, but as work in
Australia shows there will likely be degradation of the environment. Like donkeys
they compete with livestock and native animals for food and space, spread invasive
plants and diseases, foul or damage waterholes holes and cause erosion (Australian
Government 2011). Hagen and Kumschick (2018) described horses as having Major
environmental impact, but only Moderate socio-economic impact. They are not
listed as invasive alien species in the Regulations.
5.3.5 Dama dama (Fallow Deer)
Fallow Deer are native to Iran and Iraq and were introduced to South Africa from
Europe in the mid-1800s to Cape Town (prior to the oft-cited movement by CJ
Rhodes, Skead et al. 2011). This population appears to have been moved around the
Cape region, so that by 1970 Fallow Deer covered much of the Western and
Northern Cape, and these populations have expanded significantly (Skead et al.
2011), and are now present in all provinces except Limpopo (Picker and Griffiths
2011). Fallow deer are the most widely sold alien ungulate species in South Africa
(Spear and Chown 2009a). This species is an opportunistic browser, likely to
severely impact native vegetation when densities are high, by ingestion and trampling (Picker and Griffiths 2011). Regulations now prohibit the movement of fallow
deer without permits. Consequently, permits for the movement of fallow deer are
second highest for mammals (after Red Lechwe, Kobus leche leche), but only
11 game farms are permitted to stock them (van Wilgen and Wilson 2018). The
Regulations list fallow deer as a Category 2 invasive species. Their relative impacts
have not been formally assessed using EICAT or SEICAT (Blackburn et al. 2014;
Bacher et al. 2018). One of the best known populations on Robben Island is currently
the subject of control (see Chap. 23, Holmes et al. 2020), and are noteworthy for
unusual dietary behaviours including ingestion of large amounts (up to 2 L) of
plastic (C. Wilke pers. comm.), stranded kelp, newspaper or cardboard and even a
rabbit carcass (Sherley 2016).
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been shown to negatively affect Burrowing Owls, Athene cunicularia elsewhere
(Holmes et al. 2003), the horses may be similarly affecting the burrow-nesting
swallows. Another population is in Rooisands Nature Reserve and surrounding
properties near Kleinmond in the Western Cape. No data are available in the formal
literature on either population. Muller and Bourne (2018) report on a population of
>100 feral horses in the Steinkopf area of the Northern Cape province, and suggest
that there may be significant competition with domestic livestock in that area.
Throughout the world, feral horses cause degradation and a decline in ecological
integrity (Porfirio et al. 2017). Affects would be context-dependant, but as work in
Australia shows there will likely be degradation of the environment. Like donkeys
they compete with livestock and native animals for food and space, spread invasive
plants and diseases, foul or damage waterholes holes and cause erosion (Australian
Government 2011). Hagen and Kumschick (2018) described horses as having Major
environmental impact, but only Moderate socio-economic impact. They are not
listed as invasive alien species in the Regulations.
5.3.5 Dama dama (Fallow Deer)
Fallow Deer are native to Iran and Iraq and were introduced to South Africa from
Europe in the mid-1800s to Cape Town (prior to the oft-cited movement by CJ
Rhodes, Skead et al. 2011). This population appears to have been moved around the
Cape region, so that by 1970 Fallow Deer covered much of the Western and
Northern Cape, and these populations have expanded significantly (Skead et al.
2011), and are now present in all provinces except Limpopo (Picker and Griffiths
2011). Fallow deer are the most widely sold alien ungulate species in South Africa
(Spear and Chown 2009a). This species is an opportunistic browser, likely to
severely impact native vegetation when densities are high, by ingestion and trampling (Picker and Griffiths 2011). Regulations now prohibit the movement of fallow
deer without permits. Consequently, permits for the movement of fallow deer are
second highest for mammals (after Red Lechwe, Kobus leche leche), but only
11 game farms are permitted to stock them (van Wilgen and Wilson 2018). The
Regulations list fallow deer as a Category 2 invasive species. Their relative impacts
have not been formally assessed using EICAT or SEICAT (Blackburn et al. 2014;
Bacher et al. 2018). One of the best known populations on Robben Island is currently
the subject of control (see Chap. 23, Holmes et al. 2020), and are noteworthy for
unusual dietary behaviours including ingestion of large amounts (up to 2 L) of
plastic (C. Wilke pers. comm.), stranded kelp, newspaper or cardboard and even a
rabbit carcass (Sherley 2016).
124
J. Measey et al.