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Transitioning from trials to pest control tool, the efficacy of controlling waspsVespula vulgarisandV. germanicausing Vespex® wasp bait was tested in 2015. Vespex® is a protein-based bait matrix with 0.1% fipronil. Five sites ranging <300 to >2000 ha and over 5500 ha in total had bait stations placed 300 × 50 m apart and received one application of Vespex®. Wasp nest traffic rates declined 93% in four days at one site, and over 97% after 20–38 days at all other sites. Measured honeydew availability also improved post wasp control. Further demonstrating feasibility, five different agencies worked closely with government leading many programme aspects. Vespex® was made more widely available in New Zealand towards the end of 2015. Web page information showed ∼30% of all territorial authorities nationally are engaging in pest wasp problems. This signals a future potential in the way that pest wasps might be managed in a community context for social, economic and biodiversity conservation objectives. [ABSTRACT FROM AUTHOR]

Carpoglyphus wardleorum n. sp. (Astigmatina: Carpoglyphidae) is described from males and females collected from sooty mould fungi on the bark of black beech, Nothofagus solandri, at Ashley Gorge, Canterbury, New Zealand. [ABSTRACT FROM AUTHOR]

Toxic honey is produced in New Zealand when honey bees (Apis mellifera) forage on honeydew containing the phytotoxin tutin that is produced by the passion vine hopper (Scolypopa australis) when feeding on the poisonous plant tutu (Coriaria arborea). Observational studies suggest that there are a set of conditions required for the production of toxic honey, but these factors have not been well studied. This research aims to investigate the importance of altitude and weather conditions for the production of toxic honey in New Zealand and makes some recommendations for a review of the New Zealand Food Safety Authority (NZFSA) Food (tutin in honey) Standard 2008 that was introduced after a toxic honey outbreak in 2008. Transects were established in parts of the North Island during the summer of 2009 and were visited weekly for 6 consecutive weeks. Variables recorded were elevation, S. australis density, honeydew abundance, honey bee and wasp (Vespula spp.) presence and temperature and rainfall data. Weather conditions present during the 2008 outbreak were compared with those from 1999 to 2009. S. australis were not present at altitudes of 375 m and above; with more research, some higher areas of New Zealand may be able to be reclassified as 'low risk'. Honeydew was available in a wide range of temperature and rainfall conditions. Rainfall appeared to wash honeydew from tutu bushes; however, it quickly reappeared in densely populated sites. Honey bee and wasp presence was positively affected by the presence of honeydew, nevertheless 30-50% of the time they were observed foraging in the absence of honeydew, indicating they may feed on small amounts of dew. As the absence of honeydew is an option given by the NZFSA to demonstrate honey safety, this requires investigation. Weather conditions leading up to the 2008 toxic honey outbreak were warm and dry but were not significantly different from other years. Therefore, inadequate management practices, rather than more favourable environmental conditions were probably responsible for the 2008 toxic honey outbreak. Future research should focus on determining the conditions required for toxic levels of honeydew to be incorporated into hives, and regions that have not produced toxic honey historically should be closely studied to determine whether any fit the low-risk criteria. [ABSTRACT FROM AUTHOR]

Sugar-rich honeydew production by phloem-feeding sooty beech scale insects (Ultracoelostoma spp.) is a keystone ecological process in New Zealand beech (Nothofagus) forest. A dynamical model to describe the formation of individual honeydew droplets is derived using simple fluid dynamics. The model assumes that the insects play little part in regulating flow, and that flow is driven by phloem hydrostatic pressure and regulated by environmental conditions affecting water evaporation from droplets. The model predicts different types of behaviour depending on local environmental conditions. In dry conditions, evaporation rates are high and honeydew droplets can become so concentrated that further excretion is prevented and droplet formation ceases. In humid conditions, the high concentrations required to prevent droplet formation do not occur and droplets continue to grow indefinitely. The model is fitted to new data and the data are used to estimate values for the rate of flow of phloem sap through the insect and for the concentration required to prevent further excretion. Model predictions provide a close qualitative match to field data. However, rates of fluid flow from the trees through the insects would need to be much greater than the model assumes to produce values for droplet production that match field data. This suggests that the insects are playing an active role in regulating the flow rate. [Copyright &y& Elsevier]

1. The degree of infestation by New Zealand sooty beech scale insects ( Ultracoelostoma assimile, Homoptera: Margarodidae) varies dramatically among adjacent southern beech trees ( Nothofagus spp., Fagaceae), but has previously been assumed to be uniformly or randomly distributed within individual host trees. In this study, a full-census survey was conducted from ground level to canopy level on 14 naturally occurring, canopy-dominant red beech ( Nothofagus fusca) trees (size range 38.7–107.6 cm diameter at breast height) to determine the degree of within-tree heterogeneity in herbivore density. 2. The within-tree distribution of the sooty beech scale was vertically stratified and highly heterogeneous, with the greatest densities occurring on bark surfaces in the canopy rather than on the trunk, and on the lower rather than upper sides of the branches. The spatial distribution was strongly negatively correlated with trunk and branch diameter, and increasing bark thickness (as a function of diameter) provides a plausible explanation for differences in the establishment and population density of sooty beech scale insects with trunk and branch size. Furthermore, there was a significant change in the spatial distribution of scale insect populations on trunks and branches of trees of increasing diameter at breast height. This indicates a strong temporal component to the spatial dynamics of the sooty beech scale insect driven by changing host phenology. Future studies on phytophagous insects infesting large host trees need to consider more explicitly changes in population dynamics through space and time. 3. Because of the high degree of within-tree heterogeneity in population density, the total population size of scale insects on an individual tree could not be predicted from any measure of population density low on the trunk. However, the dry weight biomass of sooty mould fungi growing on the ground beneath infested trees was a remarkably accurate predictor of the total population size of scale insects. The use of sooty mould fungi as a relative measure of population size could be incorporated into studies of other honeydew-producing hemipterans, since the growth of sooty mould is a distinctive feature synonymous with high concentrations of honeydew production worldwide. [ABSTRACT FROM AUTHOR]

1. Intraspecific competition can be an important factor influencing the individual fitness of organisms. This study reports density-dependent effects on the fecundity of the beech scale insect ( Ultracoelostoma assimile, Hemiptera: Margarodidae) on naturally occurring, canopy-dominant red beech ( Nothofagus fusca, Fagaceae) trees in New Zealand. For the first time an increasing intensity of intraspecific competition at increasing spatial scales within individual host trees is demonstrated. 2. Beech scale insect ‘tests’ containing adult female scale insects and eggs were collected from the trunks of 10 red beech trees [17.7–48.5 cm in diameter at breast height (1.4 m), d.b.h.] with varying densities of scale insect infestation. The relationship between individual female fecundity and scale insect density at three spatial scales: local (within 5 cm), lower trunk (below 2 m above ground level), and whole tree, was tested. 3. Beech scale insect fecundity was density dependent, with total female egg load decreasing with increasing scale insect density. The strength of the density-dependent effect increased with increasing spatial scale, suggesting that scale insects are creating a tree-wide drain on the quality of phloem sap, rather than depleting nutrients from localised, high-density areas within trees. These results indicate that at high densities, the New Zealand beech scale insect can have a negative effect on the nutritional quality of the phloem of red beech, thus negatively affecting conspecifics elsewhere on individual host trees. The increasing intensity of the effect with increasing spatial scale within individual trees emphasises the importance of measuring density-dependent effects at the appropriate spatial scale. [ABSTRACT FROM AUTHOR]