Overview: The spread of the Portuguese millipede
The Portuguese millipede, an invasive and highly adaptable species first drawing attention on Wellington’s south coast, is now being reported in areas beyond the region. Known for its glossy black body with a red or brown banded appearance, this pest has become a nuisance for households, gardens, and damp indoor spaces. Local authorities and scientists say the spread is likely driven by human activity, weather patterns, and the millipede’s ability to survive in varied microhabitats.
What makes this millipede concerning
Unlike native millipedes, the invasive Portuguese millipede thrives in urban waterways, compost heaps, and homes, often appearing in shoes, bags, beds, and other living spaces. It emits a defensive chemical that can irritate skin and eyes, and it can survive in a wide range of temperatures and humidity levels. The species’ rapid reproduction and ability to hitchhike on outdoor gear, vehicles, and transported soil or plant material have amplified its reach beyond the initial outbreak sites.
Where the spread is being reported
Residents across coastal communities and inland suburbs have begun reporting sightings. While Wellington remains a hotspot, local pest control specialists have documented a growing number of incidents in nearby towns and rural properties. Entomologists caution that the true extent of spread may be underreported, as many individuals encounter these millipedes in minor, easily overlooked numbers.
Potential impacts on households and ecosystems
For households, the invaders can invade living spaces in search of moisture and shelter, creating concerns about cleanliness and discomfort. In gardens, they can feed on plant matter and organic debris, potentially altering soil conditions and microhabitats. Ecologically, the arrival of a non-native millipede disrupts local arthropod communities and could affect decomposer dynamics. Authorities stress that while most encounters are nuisances rather than dangerous threats to humans, the ecological ripple effects warrant careful monitoring.
What authorities are doing
Local councils and national biocontrol agencies are prioritizing surveillance, public reporting, and education. Response plans typically include guidance on sealing entry points, reducing damp habitats around homes, and safe disposal of found insects. In some cases, targeted baits and environmentally safe pesticides may be employed where infestations are confirmed, always following regulatory guidelines to protect non-target species and waterways.
How residents can protect their homes
Prevention is the key to minimizing encounters with the Portuguese millipede. Practical steps include: keeping homes dry and well-ventilated, sealing gaps under doors and around pipes, removing clutter where millipedes can hide, and regularly cleaning entryways. Outdoor management involves clearing leaf litter, decaying wood, and excess organic material, while ensuring outdoor lighting does not attract many insects at night. If you spot a millipede indoors, capture it safely in a container for identification and report the sighting to local pest control or council services.
What to watch for when traveling or moving goods
Since hitchhiking is a common spread mechanism, people who travel with outdoor gear, campers, or gardeners should inspect items before bringing them indoors. Washing boots, bags, and equipment and avoiding leaving damp gear near entry points can reduce accidental transport. If you operate a business that handles soil or plant materials, strict sanitation and quarantine practices help prevent accidental dispersal.
Looking ahead
Experts emphasize that ongoing monitoring and community engagement will shape the response. Public awareness campaigns encourage homeowners to report sightings promptly, enabling faster containment and more precise data collection. While the Portuguese millipede’s expansion is a challenge for the Wellington region and its neighbors, coordinated efforts between residents, councils, and scientists aim to limit ecological disruption and protect homes from recurring invasions.
