Namibian Invasive Alien Species Working Group

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Invasive alien species in Namibia

One of the tasks of the working group is to more clearly define which species are invasive aliens.

In Namibia, approximately 38 trees or large shrubs, 62 forbs and 24 grasses are considered invasive alien plants, 15 of which are serious economic and ecological threats. Many of the invasive shrubs are cactus species that flourish in Namibia’s arid environments, while aquatic weeds can choke the few permanent water sources in the country. Dry riverbeds and other disturbed areas are particularly vulnerable to invasion, which diminishes groundwater.

Several invasive alien animal species have been recorded in Namibia, including seven fishes, three reptiles, seven birds, four snails, one crayfish, two mussels and seven mammals. Eleven of these are considered serious threats to our native species. Besides outcompeting local species for space and resources (often the main threat), some invasive alien animals are similar enough to our native animals to interbreed with them and thus pose a genetic problem.

Plants

Fish

  • seven species

Reptiles

  • three species

Birds

  • Mallard Anas platyrhynchos Linnaeus, 1758; A. p. platyrhynchos Linnaeus.
  • Rock Dove (Feral Pigeon) Columba livia Gmelin, 1789.
  • Rose-ringed Parakeet Psittacula krameri Scopoli, 1769; P. k. borealis Neumann, 1915.
  • House Crow Corvus splendens Vieillot, 1817; C. s. splendens Vieillot.
  • Common Myna Acridotheres tristis Linnaeus, 1766.
  • Common Starling Sturnus vulgaris Linnaeus, 1758; S. v. vulgaris Linnaeus.
  • House Sparrow Passer domesticus Linnaeus, 1758; P. d. domesticus (Linnaeus).
» Download a species list with more details.

Snails

  • four species

Crayfish

  • one species

Mussels

  • two species

Mammals

  • seven species


<i>Datura innoxia</i>. Photo C Mannheimer
Psittacula krameri. Photo: Bernard Spragg (public domain)
Prosopis chilensis. Photo C Mannheimer
Salvinia molesta. Photo C Mannheimer