City needs help monitoring invasive wasps
Two highly invasive wasp species are expanding their range throughout Cape Town and the Western Cape. The City and its partners are calling on the public to help identify and report new colonies.

The European paper wasp (Polistes dominula) and the German wasp or yellow-jacket (Vespula germanica) have found the Cape Metro and the Boland to be an ideal habitat suited for their expansion. If left uncontrolled, they may spread to the majority of towns in the Western Cape and other provinces where the climate is even more suited to their requirements.

 

European wasp. Image from http://www.invasives.org.za/

European wasp. Image from http://www.invasives.org.za/

Both species are listed as National Environmental Management Biodiversity Act (NEMBA) category 1b invasive species. These species require control by means of an invasive species management programme.

According to international cases of invasion involving both species, these insects have the potential to create problems ranging from being a nuisance to serious economic impacts in the wine, deciduous fruit and beekeeping industries.

The German wasp in particular is aggressive and there are several reported cases of them stinging workers harvesting grapes and other fruits. They can present a hazard to residents enjoying the outdoors who may unintentionally disturb a colony. These wasps also feed on mature grapes in the late summer months and cause extensive damage to vineyards.

They are also known to attack and kill honeybees and infiltrate bee hives, which is detrimental to the honey industry.

 

German Wasp. Image from http://www.capetowninvasives.co.za/

German Wasp. Image from http://www.capetowninvasives.co.za/

Research is currently being implemented by the South African National Biodiversity Institute’s (SANBI) Invasive Species Programme, which is funded by the Department of Environmental Affairs. They are trying to determine the rate of expansion and document new colonies to find solutions to control the spread of both invasive insect species.

The project is managed by a consortium of researchers from the Stellenbosch University, SANBI, the University of Cape Town, the Agricultural Research Council, CapeNature, Iziko Museums, and the City of Cape Town’s Invasive Species Unit.
The research programme is now in its second phase and will move to experimental trials on the effectiveness of local eradication of both species.

The City and its partners are therefore calling on the public to assist in documenting new colonies by reporting their localities online so that the appropriate measures can be taken to control these invaders.
The European paper wasp:

The European paper wasp is a medium-sized wasp (20 mm to 35mm) with wavy yellow and black markings on the abdomen and orange antennae.

Areas found include:

Brackenfell

Kraaifontein

Kuils River

Stellenbosch

Somerset West

Gordon’s Bay

Paarl

Grabouw

Franschhoek

Wellington

The German wasp:


The German wasp is also a medium-sized wasp (15 mm to 40mm) with yellow and black markings on the abdomen but it has black antennae. A record of 750 000 wasps was recorded on a farm in Somerset West in 2002. The German wasp is aggressive, especially if the nest or surrounding areas are disturbed.

Areas found includes:

Stellenbosch

Somerset West

Grabouw

Franschhoek

Paarl

Wellington

For more information, for photos, and to report sightings, visit http://www.capetowninvasives.org.za/edrr/target-list or

e-mail EDRR@capetown.gov.za 

ISSUED BY:
INTEGRATED STRATEGIC COMMUNICATION AND BRANDING DEPARTMENT, CITY OF CAPE TOWN