Exotic mosquito species established in New Zealand

The presence of exotic mosquito species in Aotearoa New Zealand increases the risk of mosquito-borne disease outbreaks here.

No new exotic mosquito species introduced to New Zealand in 2020.

• The Culex sitiens, first discovered in Kaipara Harbour in 2018, was eradicated in 2020
• As of 2020, there are three long-established exotic mosquito species in New Zealand
• The Southern Saltmarsh mosquito (Aedes camptorhynchus), first discovered in New Zealand in 1998, was eradicated in 2010

No new exotic mosquito species were introduced in 2020. There are currently three long-established exotic species present in New Zealand. The eradication of the Southern saltmarsh mosquito (Aedes camptorhynchus) in 2010 has been the most important change to New Zealand’s mosquito profile in recent years (Table 1). 

Table 1: New Zealand’s recent history of exotic mosquito introductions

Data source: New Zealand BioSecure, 2021 [1]

Recent developments

In 2018, the Ministry for Primary Industries (MPI) first reported finding Saltmarsh Culex (Culex sitiens) larvae in the Kawau Parua Inlet, Kaipara Harbour (Auckland Region) through the National Saltmarsh Mosquito Surveillance Programme. In 2020, MPI announced the eradication of the Culex sitiens from New Zealand, two  years after larvae were initially detected. The eradication was the result of a successful ground surveillance and aerial spraying programme. Culex sitiens is a vector of Ross River virus and possibly Japanese encephalitis [2].

References

1. New Zealand BioSecure Entomology Laboratory. New Zealand Mosquitoes. Southern Monitoring Services Limited. (Accessed February 2021). Available at: www.smsl.co.nz

2. MPI (Ministry for Primary Industries). Alerts: Culex stitiens. (Accessed February 2021). Available at: www.mpi.govt.nz