Establishment patterns of non-native insects in New Zealand

Biosecurity and post-arrival pathways in New Zealand: relating alien organism detections to tourism indicators

Between-country tourism is established as a facilitator of the spread of invasive alien species; however, little attention has been paid to the question of whether tourism contributes to the arrival and subsequent dispersal of exotic organisms within national borders. To assess the strength of evidence that tourism is a driver for the accidental introducing and dispersal of exotic organisms, we sourced three national databases covering the years 2011 to 2017, namely international and domestic hotel guest nights and national population counts, along with records of exotic organism detections collected by the Ministry for Primary Industries, New Zealand’s government agency that oversees biosecurity. We fitted statistical models to assess the strength of the relationship between monthly exotic organism interception rate, guest nights and population, the latter as a baseline. The analysis showed that levels of incursion detection were significantly related to tourism records reflecting the travel of both international and domestic tourists, even when population was taken into account. There was also a significant positive statistical correlation between the levels of detection of exotic organisms and human population. The core take-home message is that a key indicator of within-country human population movement, namely the number of nights duration spent in specific accommodation, is statistically significantly correlated to the contemporaneous detection of exotic pests. We were unable to distinguish between the effects of international as opposed to domestic tourists. We conclude that this study provides evidence of impact of within-country movement upon the internal spread of exotic species, although important caveats need to be considered.

Dataset of host records for introduced parasitoid wasp species (Hymenoptera) in New Zealand

Background

The introduction of species to new regions is occurring at an increasing rate. These introductions typically consist of species that are deliberately introduced for the purposes of biological control of pests or of species that are accidentally introduced through human-mediated transport networks.

Understanding the potential and actual impacts of these introduced species requires comprehensive information on their geographic distributions and biological associations.

However, apart from a few well-known case studies, such information is lacking for many introduced species which severely hinders further assessment of risks and impact.

New information

A dataset is provided on host associations, geographic distributions and dates of collection for both deliberately and accidentally-introduced parasitoid wasp species (Hymenoptera) in New Zealand. Information was obtained by digitising specimens from the New Zealand Arthropod Collection. Dates of records range from 1921 to 2017.

The dataset includes 1265 specimen records, representing 127 parasitoid species from 12 families, with host records for 177 host species from 61 families and eight insect orders.

These data provide baseline information to help evaluate the risk from introduced parasitoids to non-target and native species.

Accumulation of Urban Insect Pests in China: 50 Years’ Observations on Camphor Tree (Cinnamomum camphora)

Since China experienced a rapid and unprecedented process of urbanization and climate change from 1978 onwards, pest outbreaks were frequently reported on urban forests, which reflects a significant imbalance between natural regulation and human control. Based on information extracted from all journal articles and reports about insect pests on camphor tree (Cinnamomum camphora) in urban China, we characterized historical patterns and trends in pest outbreaks over large areas. Our results suggested that (1) most distribution areas of C. camphora in urban China had pest records (14 provinces) over the last 50 years, especially at the south-eastern coastal areas; (2) pests on camphor tree in urban China showed an accelerated growth since the 1990s; and (3) pests on camphor tree in urban China were characterized by native and leaf-feeding species. Urbanization seems to positively correlate with urban pest outbreaks. Changes of urban pest outbreaks could largely be described by synchronic changes of socio-economic indicators, of which CO2 emissions as metric tons per capita is the most significant predictor, followed by GDP and human population. Thus, managers and city planners should allocate resources to socio-economic-related pest outbreaks for a sustainable ecosystem.