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Supplementary Figures S1 (Spectrograms), S2 (Power Spectral Density), S3 (Power Decay), and S4 (Swarm Plots)

Additional figures related to the acoustic data analysis

International audience; Species introductions on islands result into heterogeneous assemblages with short common biogeo- graphic histories, yet potentially redundant ecological functions. How native and feral species interact over resource and habitat in the absence of long co-evolutionary histories presides to the deterministic part of assembly processes in these assemblages, in turn affecting strategies to preserve indigenous bio- diversity. Critical to this question are the ability of introduced species to cope with novel environments and their degree of niche separation with native species, which may or not permit local invasion. These processes can be investigated by studying shifts in alien species’ ecological trait space between their native and introduction ranges, and its degree of overlap with co-occuring native species on introduction grounds, accounting for the depth of their common phylogenetic histories. Previous results suggested that insular assemblages are driven either by past competitive exclusion, habitat filtering or niche dis- placement associated with post-introduction lability in species’ trait space. We attempt to disentangle these processes in New Zealand bird assemblages, which uniquely mix species from multiple biogeo- graphical origin and range from narrow endemism to colonizing alien birds. New Zealand thus hosts some of the world’s most peculiar bird assemblages, albeit without obvious conflicts among species with differing local histories. We use a multispecies hierarchical bayesian model fitted on 501 point counts to investigate niche separation between 21 alien and native species through their responses in abun- dance to habitat composition at landscape (proportion of native and man-modified habitats) and local scales (forest composition and vertical structure). Complementarily, we investigate the roles of species’ ecological trait space and biogeographical origins in these responses through an ordination framework constructed with literature data. Our results support habitat filtering operating simultaneously at multiple scales, associated with trait-based separation between native and alien species. We further present preliminary results on the contributions of biogeographic origin and phylogenetic relatedness to habitat-trait associations in New-Zealand bird assemblages, and eventually propose avenues to refine these results through novel curve analysis methods. Our framework aims to integrates functional and biogeographic perspectives on novel insular communities to the benefit of a better understanding and conservation of island biodiversity.

Land-use change creates acute trade-offs among ecosystem services that support wellbeing. We comprehensively assess trade-offs and synergies in ecosystem service provisioning across land covers. We systematically surveyed published literature (1970 – 2015) for New Zealand, to quantify 1137 individual land cover - ecosystem services relationships for 473 service provision indicators across 17 services. For each service, we used a network meta-analysis to obtain quantitative estimates of provision from each land cover. Multivariate analyses of these estimates allowed us to compare 1) land covers in the provision of multiple services, and 2) services in terms of the different land covers that provide them. We found a significant trade-off in service provision between land covers with a high production intensity against those with extensive or no production; the former providing only a limited range of services. However, our results also indicate that optimal provision of multiple services is unlikely to be met by a single land cover, but requires a combination of multiple land covers in the landscape. When applied to land-use/land-cover planning, our approach reveals: 1) land covers that cluster together, and thus provide redundancy (and potentially resilience) in service production, and 2) land covers that are likely to exhibit complementary roles in service provision because they occur at opposite extremes of the multivariate service space. It also allows identification of service bundles that respond similarly to land cover. Actively incorporating findings from different disciplines into ecosystem services research can guide practitioners in shaping land systems that sustainably support human welfare.

Species introductions on islands result into heterogeneous assemblages with short common biogeo- graphic histories, yet potentially redundant ecological functions. How native and feral species interact over resource and habitat in the absence of long co-evolutionary histories presides to the deterministic part of assembly processes in these assemblages, in turn affecting strategies to preserve indigenous bio- diversity. Critical to this question are the ability of introduced species to cope with novel environments and their degree of niche separation with native species, which may or not permit local invasion. These processes can be investigated by studying shifts in alien species’ ecological trait space between their native and introduction ranges, and its degree of overlap with co-occuring native species on introduction grounds, accounting for the depth of their common phylogenetic histories. Previous results suggested that insular assemblages are driven either by past competitive exclusion, habitat filtering or niche dis- placement associated with post-introduction lability in species’ trait space. We attempt to disentangle these processes in New Zealand bird assemblages, which uniquely mix species from multiple biogeo- graphical origin and range from narrow endemism to colonizing alien birds. New Zealand thus hosts some of the world’s most peculiar bird assemblages, albeit without obvious conflicts among species with differing local histories. We use a multispecies hierarchical bayesian model fitted on 501 point counts to investigate niche separation between 21 alien and native species through their responses in abun- dance to habitat composition at landscape (proportion of native and man-modified habitats) and local scales (forest composition and vertical structure). Complementarily, we investigate the roles of species’ ecological trait space and biogeographical origins in these responses through an ordination framework constructed with literature data. Our results support habitat filtering operating simultaneously at multiple scales, associated with trait-based separation between native and alien species. We further present preliminary results on the contributions of biogeographic origin and phylogenetic relatedness to habitat-trait associations in New-Zealand bird assemblages, and eventually propose avenues to refine these results through novel curve analysis methods. Our framework aims to integrates functional and biogeographic perspectives on novel insular communities to the benefit of a better understanding and conservation of island biodiversity.

National audience

1. Dispersal and host detection are behaviours promoting the spread of invading populations in a landscape matrix. In fragmented landscapes, the spatial arrangement of habitat structure affects the dispersal success of organisms. 2. The aim of the present study was to determine the long distance dispersal capabilities of two non‐native pine bark beetles (Hylurgus ligniperda and Hylastes ater) in a modified and fragmented landscape with non‐native pine trees. The role of pine density in relation to the abundance of dispersing beetles was also investigated. 3. This study took place in the Southern Alps, New Zealand. A network of insect panel traps was installed in remote valleys at known distances from pine resources (plantations or windbreaks). Beetle abundance was compared with spatially weighted estimates of nearby pine plantations and pine windbreaks. 4. Both beetles were found ≥25 km from the nearest host patch, indicating strong dispersal and host detection capabilities. Small pine patches appear to serve as stepping stones, promoting spread through the landscape. Hylurgus ligniperda (F.) abundance had a strong inverse association with pine plantations and windbreaks, whereas H. aterabundance was not correlated with distance to pine plantations but positively correlated with distance to pine windbreaks, probably reflecting differences in biology and niche preferences. Host availability and dispersed beetle abundance are the proposed limiting factors impeding the spread of these beetles. 5. These mechanistic insights into the spread and persistence of H. ater and H. ligniperdain a fragmented landscape provide ecologists and land managers with a better understanding of factors leading to successful invasion events, particularly in relation to the importance of long‐distance dispersal ability and the distribution and size of host patches.

National audience

La partie est intégrée dans le Chapter 6: Insect – Tree Interactions in Thaumetopoea pityocampa; International audience; The pine processionary moth is, by far, the most important insect defoliator of pine forests in Southern Europe and North Africa, both in terms of its temporal occurrence, geographic range and socioeconomic impact. Monitoring and pest management actions are therefore required on a regular basis, to ensure the detection, evaluation and mitigation of potential risks to forest and public health. However, we still lack some of the basic knowledge required for relevant analyses of the risk posed by the pine processionary moth. Pest risk is defined as a combination of three components: (1) pest occurrence, which depends on the spatiotemporal dynamics of populations; (2) plant vulnerability to the pest, resulting in a certain amount of damage; and (3) the socioeconomic impact of damage, depending on the potential value of the plants damaged (Jactel et al. 2012). The population dynamics of the processionary moth has been extensively studied, in particular within the context of climate change (see Battisti et al. 2014, Chap. 2, this volume). Several studies have recently addressed the question of tree and forest vulnerability to pine processionary attacks but a comprehensive review of evidence was missing. This is the first objective of this chapter. In particular we were interested in a better understanding of the ecological mechanisms responsible for the host tree selection, at both the species and individual tree levels. In a second part we show that pine susceptibility to the pine processionary moth could be reduced by improving forest diversity at different spatial scales. In the last part of this chapter we provide quantitative estimate of the growth losses caused by defoliations of the pine processionary moth. Altogether this information paves the way for quantitative risk analyses on pine processionary moth infestations based on forest growth models.

Wood borers and bark beetles are among the most serious forest pests worldwide. Many such species have become successful invaders, often causing substantial, costly damages to forests. Here we design and evaluate the cost-efficiency of a trap-based surveillance program for early detection of wood borers and bark beetles at risk of establishing in New Zealand. Though costly, a surveillance program could lead to earlier detection of newly established forest pests, thereby increasing the likelihood of successful eradication and reducing control costs and damages from future invasions. We develop a mechanistic bioeconomic model that relates surveillance intensity (i.e., trap density) and invasion size to probabilities of detection and control; it captures the dynamics of invasive species establishment, spread, and damages to urban and plantation forests. We employ the model to design surveillance programs that provide the greatest net present benefits. Our findings suggest that implementing a surveillance trapping program for invasive wood borers and bark beetles would provide positive net benefits under all scenarios considered. The economically optimal trapping strategy calls for a very high investment in surveillance: about 10,000 traps in each year of the 30-year surveillance program, at a present value cost of US$54 million. This strategy provides a 39% reduction in costs compared with no surveillance, corresponding to an expected net present benefit of approximately US$300 million. Although surveillance may provide the greatest net benefits when implemented at relatively high levels, our findings also show that even low levels of surveillance are worthwhile: the economic benefits from surveillance more than offset the rising costs associated with increasing trapping density. Our results also show that the cost-efficiency of surveillance varies across target regions because of differences in pest introduction and damage accumulation rates across locales, with greater surveillance warranted in areas closer to at-risk high-value resources and in areas that receive more imported goods that serve as an invasion pathway.

Wood borers and bark beetles are among the most serious forest pests worldwide. Many such species have become successful invaders, often causing substantial, costly damages to forests. Here we design and evaluate the cost-efficiency of a trap-based surveillance program for early detection of wood borers and bark beetles at risk of establishing in New Zealand. Though costly, a surveillance program could lead to earlier detection of newly established forest pests, thereby increasing the likelihood of successful eradication and reducing control costs and damages from future invasions. We develop a mechanistic bioeconomic model that relates surveillance intensity (i.e., trap density) and invasion size to probabilities of detection and control; it captures the dynamics of invasive species establishment, spread, and damages to urban and plantation forests. We employ the model to design surveillance programs that provide the greatest net present benefits. Our findings suggest that implementing a surveillance trapping program for invasive wood borers and bark beetles would provide positive net benefits under all scenarios considered. The economically optimal trapping strategy calls for a very high investment in surveillance: about 10,000 traps in each year of the 30-year surveillance program, at a present value cost of US$54 million. This strategy provides a 39% reduction in costs compared with no surveillance, corresponding to an expected net present benefit of approximately US$300 million. Although surveillance may provide the greatest net benefits when implemented at relatively high levels, our findings also show that even low levels of surveillance are worthwhile: the economic benefits from surveillance more than offset the rising costs associated with increasing trapping density. Our results also show that the cost-efficiency of surveillance varies across target regions because of differences in pest introduction and damage accumulation rates across locales, with greater surveillance warranted in areas closer to at-risk high-value resources and in areas that receive more imported goods that serve as an invasion pathway.

International audience

International audience; The life cycle and seasonal phenology of the endemic geometrid Pseudocoremia suavis (Butler) is described, as well as a method for rearing the species continuously in the laboratory on cut foliage of radiata pine (Pinus radiata D.Don). Both males and females demonstrated developmental polymorphism, having either five (Type I) or six (Type II) larval instars. These two larval types did not differ significantly in the total development time (from egg hatch to adult) of around 60 days in either case.The development time and head capsule widths of the penultimate and ultimate instars of each type suggest that these two instars are equivalent in both Type I and Type II larvae. In the field, most instars were present throughout the sampling period from mid-November to mid-March, and no clear peaks in activity were observed for adult males caught on female-baited sticky traps. These results support the findings of others that this species does not have clearly synchronised generations. Catch data from femalebaited traps revealed that calling peaked in one-day old females, with a mean of c. 27% of catches, and declined steadily with age. About 99% of cumulative catches occurred by the time females were 12 days old

Conference: 55. Annual Conference of the New-Zealand-Plant-Protection-Society, Rotorua (Nouvelle-Zélande), 2002-08-13/2002-08-15; International audience; Several leafroller species (Tortricidae) are known to occasionally cause considerable defoliation in Pinus radiata plantation forests We conducted pheromone trapping for five indigenous species Ctenopseustis herana Ctenopseustis obliquana Planotortrix excessana Planotortrix notophaea and Planotortrix octo and the exotic Epiphyas postvittana to determine their abundance in 20 P radiata stands in Eyrewell Forest North Canterbury Trapping from December 2001 to February 2002 indicated that E postvittana and C obliquana were very abundant (with mean catches of 077 and 044 moths/trap/day respectively) while the other species were rarely caught Results for the native leafrollers differ considerably from those reported from other plantation forests and other habitats in Canterbury such as apple orchards where P octo and C herana are generally more common.

Chapter 4: Impacts of biological invasions on nature, nature’s contributions to people, and good quality of life of the Thematic Assessment Report on Invasive Alien Species and their Control of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services., Suggested citation: Bacher, S., Galil, B. S., Nuñez, M. A., Ansong, M., Cassey, P., Dehnen-Schmutz, K., Fayvush, G., Hiremath, A. J., Ikegami, M., Martinou, A. F., McDermott, S. M., Preda, C., Vilà, M., Weyl, O. L. F., Fernandez, R. D., and Ryan-Colton, E. (2023). Chapter 4: Impacts of biological invasions on nature, nature's contributions to people, and good quality of life. In: Thematic Assessment Report on Invasive Alien Species and their Control of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Roy, H. E., Pauchard, A., Stoett, P., and Renard Truong, T. (eds.). IPBES secretariat, Bonn, Germany. https://doi.org/10.5281/zenodo.7430731