New Zealand supports rich temperate forests believed to have occupied up to 80% of its land area below climatic tree line prior to human arrival in the 11th century, but deforestation, particularly motivated by conversion to agricultural systems in the last 150 years, has decreased today’s forest cover to less than 30% of the original estimate. There is currently interest in relatively large-scale afforestation of degraded lands, and this has initiated research and development to improve seeding of native forest species. We provide a synthesis of available literature, ongoing research, and practical experience to identify critical aspects of candidate afforestation sites, summarize practices and techniques used in current seeding research and operations, and recognize factors that affect success or failure of seeding native species. The main challenges are that pastoral farming has dramatically altered the soil microbiome, non-native mammalian herbivores and weeds reduce seedling establishment success, and many native trees are mast seeding or have recalcitrant seeds. Selection of sites with predictably adequate rainfall, deployment of fast germinating pioneer species, procurement of high-quality seed, availability of appropriate soil symbionts, and post-establishment weed and animal control are all important components of success when seeding native forest species in New Zealand.

ABSTRACT Both citizen science observations and taxonomic collections provide valuable data on species occurrences, typically including species identification, as well as the time and place of observation or collection. Comparing these datasets is intuitive and important for understanding biodiversity patterns. In this study, over 86,000 records of exotic insect species in New Zealand were obtained from the Global Biodiversity Information Facility, comprising two record types: citizen science observations (from iNaturalist) and specimen records (from digitised museum collections). These datasets were compared across taxonomic levels, temporal and geographic scales, and species body size. Key differences emerged between the two data sources. Although the total number of exotic insect records was similar, exotic species accounted for a greater proportion of citizen science observations (1 in 5) than specimen records (1 in 10). Taxonomic composition varied significantly between the datasets at the order, family, and species levels, with citizen science observations disproportionately representing larger-bodied species. Consequently, many exotic insect species present in New Zealand were underrepresented in observation records. Despite these biases, the large volume of citizen science data makes it a valuable resource for biosecurity and invasion biology. Enhancing public awareness of diverse insect groups, including smaller or less conspicuous species, could improve data coverage. Ultimately, leveraging the complementary strengths of both record types will enhance biodiversity monitoring and biosecurity efforts.

ABSTRACT A checklist and synopsis of the family Braconidae (Hymenoptera) that are present in New Zealand is provided. The fauna consists of 17 subfamilies, 74 genera, and 147 described species (99 indigenous, 48 exotic). A large portion of the taxonomic names previously listed in the catalogue of Valentine and Walker (1991) have changed or are new. Twenty-five new indigenous species have been described in the last ten years and 57 species since the year 2000. Two species previously recorded are now not considered present, Fopius carpocapsae (Ashmead, 1900) and Parallorhogas pallidiceps (Perkins, 1910). Currently 83% of genera and 52% of described species in New Zealand have a COI barcode sequence. The indigenous Braconidae fauna is estimated at over 400 species, indicating only ∼25% of indigenous species are currently described.

Context Phylogeographic patterns can reveal the physical environmental processes that shape biodiversity. Marine species often have dispersive larval stages, but might not be well-connected over large distances. Sand dollars, for example, often show regional isolation but local connectivity. Aims This study sought to quantify the population genomic structure of the New Zealand sand dollar, Fellaster zelandiae. Methods Sequencing of the cytochrome c oxidase I (COI) gene fragment determined the phylogenetic relationship of Fellaster with other sand dollars globally, and genotyping-by-sequencing (40,725 single-nucleotide polymorphisms) revealed the phylogeography of this species around New Zealand. Key results The genus Fellaster was resolved as sister to its Australian counterpart, Arachnoides. Fellaster zelandiae showed evidence of strong connectivity among populations. Conclusions Small-scale genetic variation between northern and southern populations appears to be consistent with biogeographic patterns seen in other coastal species in New Zealand and is probably driven by isolation of some regions by oceanographic features incluing the East Auckland Current, East Cape Current and Southland Current. Implications While the strong connectivity of many contemporary Fellaster zelandiae populations is likely to be the result of a long-lived larval stage, gene flow may reduce in the future if larval development times decrease.

Recently, the first representatives of endemic simplidactylate landhoppers in the ancient family Arcitalitridae were recognised from New Zealand. This study reveals the existence of a second endemic genus, Koekotroides gen. nov., from this family in New Zealand. Six new species of Koekotroides gen. nov. are described from native vegetation in the North Island of New Zealand and some of its offshore islands: K.moowhitihauuru sp. nov., K.taapinea sp. nov., K.tewhaarua sp. nov., K.maene sp. nov., K.pekehau sp. nov., and K.ngaokiroa sp. nov. Five of the six species were subjected to genetic investigation. There was generally good agreement between the taxon delineation determined from morphological analysis and that from sequence analysis of the mitochondrial 16S locus. The genus appears to have a centre of diversity in the northern North Island and the Three Kings and Poor Knights Islands each have their own species. Ancestors of Koekotroides presumably arrived in Zealandia before it rifted from Gondwana during the later Cretaceous. This brings the total number of described native landhopper species in New Zealand to 35 and increases the number of described arcitalitrids to nine.

Identifying contemporary population structure and genetic connectivity among seabird populations is essential for developing conservation plans for threatened species, especially as factors like philopatry, non-breeding behavior, and oceanographic features might limit gene flow between isolated populations and influence changes in genetic diversity over time. Here, we characterize the population structure of three closely related crested penguin species in New Zealand: Tawaki (Eudyptes pachyrhynchus; Fiordland penguins), erect-crested penguins/tawaki nana hī (Eudyptes sclateri), and eastern rockhopper penguins/tawaki piki toka (Eudyptes filholi). Whereas tawaki populations appear to be stable, the erect-crested and eastern rockhopper penguin populations have seen dramatic declines in the recent historical record. To understand the genetic implications of these differences in population trajectories, we assessed genetic connectivity among multiple colonies using thousands of nuclear autosomal loci. Our results indicate that tawaki are a single, genetically diverse population without colony-based structure, which is consistent with the currently observed stable or increasing population of tawaki. However, conservation efforts should continue to prioritize protecting marine habitats to safeguard this species. In contrast, we identified two genetically distinct populations of erect-crested penguins corresponding to the Antipodes Islands and the Bounty Islands groups. The Antipodes Islands eastern rockhopper population exhibited high levels of coancestry and low genetic diversity, consistent with population decline and limited immigration. The lack of gene flow and genetic diversity in both erect-crested and eastern rockhopper penguins on the Antipodes Islands raises concerns and highlights the need for continued research to identify the causes of declines to inform conservation efforts of these penguins.

Abstract The two egg parasitoids Enoggera nassaui (Girault) and Neopolycystus insectifurax Girault (both Hymenoptera: Pteromalidae) are biological control agents of the eucalyptus-defoliating paropsine leaf beetle Paropsis charybdis Stål (Coleoptera: Chrysomelidae), an invasive species in New Zealand. Recently another leaf beetle, Paropsisterna cloelia (Stål) (Coleoptera: Chrysomelidae), has established in New Zealand, causing defoliation on select eucalypt hosts, e.g., Eucalyptus bosistoana. To determine if established egg parasitoids can control Pst. cloelia, the host suitability and host preferences of the two parasitoids were tested under laboratory conditions and compared with in-field egg parasitism at a site where all parasitoid and beetle species were present. Laboratory and field assessments confirmed that both parasitoids can reproduce in P. charybdis and Pst. cloelia but have a strong preference for P. charybdis. Consequently, probabilities of unparasitized Pst. cloelia larvae hatching in the laboratory or field in the presence of either parasitoid was higher compared to P. charybdis, ranging between 32-79% versus 1-24%, respectively. Offspring of both parasitoids emerged 36% larger (wing length 1.40 mm versus 1.06 mm and 1.56 mm versus 1.07 mm for E. nassaui and N. insectifurax, respectively) from P. charybdis eggs versus Pst. cloelia eggs, confirming Pst. cloelia eggs as lower quality hosts for these parasitoids. We conclude that E. nassaui and N. insectifurax will not induce sufficient mortality in Pst. cloelia eggs to be effective biological control agents for this invasive beetle.

Redwood (Sequoia sempervirens (Lamb. ex D. Don) Endl.) is a fast-growing, long-lived conifer native to a narrow coastal zone along the western seaboard of the United States. Redwood can accumulate very high amounts of carbon in plantation settings and continuous cover forestry (CCF) represents a highly profitable option, particularly for small-scale forest growers in the North Island of New Zealand. We evaluated the profitability of conceptual CCF regimes using two case study forests: Blue Mountain (109 ha, Taranaki Region, New Zealand) and Spring Creek (467 ha, Manawatu-Whanganui Region, New Zealand). We ran a strategic harvest scheduling model for both properties and used its results to guide a tactical-spatially explicit model harvesting small 0.7 ha units over a period that spanned 35 to 95 years after planting. The internal rates of return (IRRs) were 9.16 and 10.40% for Blue Mountain and Spring Creek, respectively, exceeding those considered robust for other forest species in New Zealand. The study showed that small owners could benefit from carbon revenue during the first 35 years after planting and then switch to a steady annual income from timber, maintaining a relatively constant carbon stock under a continuous cover forestry regime. Implementing adjacency constraints with a minimum green-up period of five years proved feasible. Although small coupes posed operational problems, which were linked to roading and harvesting, these issues were not insurmountable and could be managed with appropriate operational planning.

BACKGROUNDAccurate identification of cryptic species is critical for invasive species monitoring. Footprint surveys are often used as an indirect rodent monitoring method, but surveyors can misidentify closely related species. Machine learning techniques can reduce observer errors by enabling species identification through training of statistical algorithms on known footprints and then classifying the footprints of unknown species using the resulting models. Such a tool has important applications for the identification and biosecurity management of invasive rodents.RESULTSWe conducted a study to test the accuracy of using linear discriminant analyses (LDA) and extreme gradient boosting (XGBoost) to distinguish between footprints of two congeneric invasive rat species in New Zealand, the Pacific rat (Rattus exulans) and ship rat (Rattus rattus). We collected footprints using inked tracking tunnels and extracted geometric profiles of the footprints. We built linear discriminant and XGBoost models on known‐species footprints, undertook ten‐fold cross‐validation, and then applied models to classify footprints of unknown species. The predictive accuracies of the models were all ≥ 90%, with the front foot models (99%) slightly outperforming the hind foot models (94%).CONCLUSIONFootprint models provide a reliable tool to distinguish rat species. We discuss potential shortcomings of the models in distinguishing between adult Pacific rats and juvenile ship rats particularly across different populations. We recommend the use of tracking tunnels and footprint models for assessing invasion and reinvasion of congeneric rat species and advocate the application of this technique for identifying and distinguishing among other rodent species. © 2025 Landcare Research New Zealand Limited and The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Clarifying the determinants of environmental partitioning between ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) associations may inform predictions of the effects of climate change on global vegetation patterns, nutrient cycling, and carbon storage in forest ecosystems. Nothofagus species (southern beeches) are the only widespread ECM trees in the humid temperate forests of the southern hemisphere. Despite long-standing interest in spatial and temporal partitioning of forest environments between Nothofagus and other tree species in South America, New Zealand, and Australia, rarely has this research adopted a mycorrhizal focus. We used two-stage landslide chronosequences to examine the environmental drivers of successional trajectories of the mycorrhizal makeup of south-temperate rainforests. We used structural equation modeling (SEM) to address two hypotheses: (1) soil N:P ratios mediate the relative abilities of Nothofagus and AM trees to colonize landslide scars, and (2) soil C:N ratios determine the ability of AM trees to invade the understories of established stands and potentially replace Nothofagus. Hypothesis (1) was not supported, as mean annual temperature (MAT) was the only significant predictor of the mycorrhizal makeup of early-successional stands. Hypothesis (2) was supported, as soil C:N was the sole significant predictor of the mycorrhizal makeup of understories of established forests, being negatively correlated with AM tree representation in understories. Soil C:N in beneath established forests was in turn influenced by MAT, by % Nothofagus overstory dominance in established forests, and by soil N and N:P ratios beneath early-successional stands. Marked continental disparities in soil parent materials and typical C:N ratios underlie the well-documented differences between south-central Chile and Tasmania in the dependence of Nothofagus regeneration on exogenous disturbance. Our results leave unanswered questions about the circumstances that favor Nothofagus capture of disturbed sites but support modeling studies that have identified soil C:N ratio and inherent site nutrient status as key controls on AM/ECM dynamics in later successional stages.

Parasites play an important role in ecosystems, often exhibiting complex life cycles that involve two to four host species and transmission through trophic interactions. By tracking parasite life cycles, predator–prey links can be identified, offering valuable insights into food webs. In this study, we examined the helminth community of the mottled triplefin (Forsterygion capito), one of the most common intertidal fish species in New Zealand, using molecular techniques. We identified 14 parasite species, including one new to science and three new host records. These findings established new predator–prey links in the previously known local food web. We also provide evidence of parasite competition, focusing on the trematode Cardiocephaloides ovicorpus, the most prevalent and abundant parasite found in the brain case of F. capito. As the intensity of C. ovicorpus metacercariae increased, their individual size decreased, suggesting intraspecific competition for resources within the limited space of the brain case. Additionally, C. ovicorpus may indirectly outcompete other parasite species using F. capito by inducing host behavioural manipulation to enhance its transmission to avian hosts given its encystment site within the brain case of the fish. Overall, our findings emphasise the importance of obtaining information about parasites in order to improve our understanding of species interactions within ecosystems.

Background: Snapper is a significant commercial, recreational, and cultural teleost species in New Zealand, with aquaculture potential. The impact of long-term (chronic) temperature changes on immune and stress responses have not been studied in snapper, yet they have a critical importance to the health status of the fish. Methods: We investigated a set of genes in 30 individual snapper including fin, head kidney, and liver tissue, fish (10 per group) were exposed to either warm (22 °C), cold (14 °C), or ambient temperatures (10.5-18.6 °C) for 3 months. Results: Analyses of experimental fish using NanoString technologies to assess stress- and immune-related genes in the three tissue types showed that 22 out of 25 genes changed significantly in the experiment, indicating the significant impacts of chronic temperature changes on stress and immune responses. Furthermore, using a combined dataset based on this study and a previous one testing the impact of acute temperature changes in snapper, we identified five genes in the non-lethal fin-clip samples that can predict internal organ health status. Conclusions: Taken together, our experiments demonstrate the potential of the NanoString gene expression assessment tool for the rapid monitoring of stress responses in snapper, which can aid in the selection of stress-resilient wild stocks, monitor species in aquaculture environments, and inform the selection of locations for aquaculture.

The potential arrival of Halyomorpha halys in New Zealand jeopardizes a vast range of crops. Therefore, different preparedness strategies are being assessed before its arrival. A symbiont-targeted control strategy might be used along with other control tactics such as biological control. Prior its implementation, it is necessary to assess its potential impact on non-target stink bug species and their associated egg parasitoids. In this study, the effect of symbiont-targeted control was evaluated on three stink bug species in New Zealand, Oechalia schellenbergii (a native predatory species), Nezara viridula (a cosmopolitan pest) and Monteithiella humeralis (a non-pest adventive species). The interference of anti-symbiont treatment of egg masses with their associated Trissolcus egg parasitoids, namely T. basalis and T. oenone, was also tested. A variable response to symbiont elimination was observed in stink bug species, with N. viridula and M. humeralis undergoing high mortality and no negative effect detected for O. schellenbergii. Parasitism of N. viridula by T. basalis declined on egg masses treated with an anti-symbiont biocomplex or water. Similar results were obtained for T. oenone parasitizing eggs of M. humeralis; while, a parasitism increase was observed for O. schellenbergii egg masses exposed to anti-symbiont treatment and treated with water. These results confirm previous evidence of species-specific response to anti-symbiont control and indicate a moderate and variable effect on egg parasitism. Such responses suggest that symbiont-targeted control would not significantly interfere with the native insect communities that may interact with H. halys, encouraging the future incorporation of symbiont-targeted control in pest management programs.

ABSTRACT The green-lipped mussel, Perna canaliculus, is an important aquaculture species in New Zealand. Recently, the industry has been increasingly challenged by stressors associated with climate change. Predicting its response to climate change requires more than single-parameter measurements, as mussels show various physiological and behavioural adaptations. In this study, heart rate (HR), respiration rate ( M ˙ O 2 ), and relative gaping magnitude (RGM) of P. canaliculus were measured simultaneously under increasing temperature from 17°C to 30°C at a rate of 1°C every 20 min over seven hours. HR, M ˙ O 2 and RGM responded differently to acute temperature increase. HR peaked at 26°C, while M ˙ O 2 continued to rise until 30°C, and RGM spiked beyond 28°C. These integrated responses suggest the mussels’ upper thermal limit is around 26°C, higher than typical seawater temperatures of 20°C seen during summer heatwaves, indicating a significant thermal safety margin. Only HR and M ˙ O 2 were positively correlated, but this relationship was disrupted at higher temperatures due to higher inter-individual variabilities of those physio-behavioural responses. Variations in such responses have potential in identifying more thermally tolerant mussel lines within selective breeding programmes that ultimately may help produce mussels tolerant of a warming future.

ABSTRACT The bluegill bully is a small (TL < 100 mm) eleotrid fish that inhabits fast flowing habitats in New Zealand rivers. Bluegill bullies are amphidromous with larvae developing at sea and juveniles migrating upriver to adult rearing habitats in freshwaters. Throughout New Zealand, more than 90% of adults occur within 50 km upstream of river mouths. This species, therefore, has a relatively restricted longitudinal distribution in rivers compared with most other amphidromous fish species in New Zealand. In the Motu River, females were smaller than males (mean TL of 62 mm versus 72 mm). The mean length of both sexes increased with distance upriver, and although females dominated the population (77% of all fish), the proportion of males increased with distance upriver. Consequently, population structure in terms of both fish size and sex ratio varied with distance upriver. Due to the spatial variation in population structure, the loss of riverine connectivity resulting from anthropogenic obstructions may reduce habitat for the larger fish, especially the largest males. It may also alter population structure, thereby influencing selective pressures contributing to population fitness and further impacting populations of this vulnerable native fish.

ABSTRACT Twenty-one non-native freshwater fish species have established populations in New Zealand, yet only two have been reported with monogenean infestations; grass carp, Ctenopharyngodon idella (Valenciennes in Cuvier and Valenciennes, 1844) and western mosquitofish, Gambusia affinis (Baird and Girard, 1853), each with two identified monogenean species. Based on the diversity of monogeneans known from New Zealand's non-native freshwater fish species in their native and other invaded ranges, it is likely that many other monogeneans could be extant in the country. Accordingly, we surveyed monogeneans from seven freshwater fish species. Eleven monogenean species were found, including nine previously unreported from New Zealand. One represented a genus previously unrecorded in the country, the ancyrocephalid Ligictaluridus pricei (Mueller, 1936), infesting the gills of Ameiurus nebulosus (Lesueur, 1819). Six dactylogyrid monogenean species were found infesting Carassius auratus (L.): Dactylogyrus anchoratus (Dujardin, 1845), D. dulkeiti Bychowsky, 1936, D. formosus Kulweic, 1927, D. inexpectatus Izyumova, 1955, D. intermedius Wegener, 1909 and D. vastator Nybelin, 1924. Further, a Gyrodactylus species was observed from the gills of Carassius auratus, which could not be confidently identified to the species level. Finally, Dactylogyrus minutus Kulweic, 1927, was recorded from Cyprinus rubrofuscus Lacépède, 1803.

Abstract Fine root traits span two independent axes of variation, the conservation and collaboration axes, which define the root economic space (RES). However, whether early‐stage fine root decomposition rates (quantified as proportion mass loss, i.e. pml) are more strongly related to collaboration or conservation traits remains unclear. We studied 63 tree species in New Zealand's temperate rain forest. We determined the phylogenetic signal in pml and fine root traits, conducted phylogenetic principal component analysis and used phylogenetic generalized least squares to determine which traits are most strongly related to pml. Root decomposition exhibited a high phylogenetic signal and was more strongly related to the conservation than the collaboration axis. Root tissue density (RTD) was negatively correlated and root nitrogen (RN) was positively correlated with pml. Root diameter was positively yet weakly correlated with pml, but specific root length was uncorrelated with pml. The lignin‐to‐N ratio and root cellulose were the strongest predictors of pml. Synthesis: Early‐stage fine root decomposition is most strongly driven by tissue quality traits, such as root nitrogen, tissue density and lignin‐to‐N ratio, which all align with the conservation axis of the root economics space. However, root diameter plays a weak yet undeniable role in early‐stage fine root decomposition. Some thick‐rooted species decomposed faster, possibly due to the higher quality cortical tissue. Thin‐rooted species decomposed slower, possibly because of their higher cellulose concentration that maintains the structural integrity of small diameter roots. Relationships between decomposition and other traits that align with the collaboration gradient deserve further study across the phylogeny of vascular plants.

Spiny lobster recreational fisheries in Australia and New Zealand: An overview of regulations, monitoring, assessment and management

Specific leaf area (SLA) plays a critical role in carbon assimilation and nutrient cycling. While leaf habit (deciduous vs. evergreen) has often been recognized as a reliable predictor of SLA—with deciduous species typically having higher mean SLA values due to lower concentration of structural components compared to evergreens—high variation in SLA among evergreen species suggests further investigation of variation for species with this leaf habit could improve predictions of SLA effects on community and ecosystem processes. Furthermore, the presence of leaves of different ages in evergreen plants, emerging over multiple years, could amplify the within-individual variation in SLA, which remains underexplored. Here we report variations of SLA measured from c. 2000 leaves collected from 36 individuals across 19 woody species in an understory environment in New Zealand (NZ). We found that while most deciduous species, predominantly non-native, clustered towards higher SLA values, evergreen species presented a wide SLA spectrum. Moreover, we found that while being deciduous, having a smaller leaf size, and younger leaves, collected from lateral branches, correlated with elevated SLA values, the leaf habit did not primarily drive the within-individual SLA variation. Instead, smaller leaf size emerged as a significant predictor of within-individual SLA variation. The branch-order effect on SLA underscores a methodological consideration: accurate estimation of total leaf area in evergreen trees requires representative sampling across all branch orders. Our study also highlights the need for integrating leaf traits such as leaf size and branch order into functional trait analyses. Further research is vital to understand the underlying mechanisms of these trait variations and their impacts on ecosystem functioning.

Societal Impact StatementDust seeds, which are minute and contain minimal energy reserves, are often associated with heterotrophy (plants that obtain carbon without photosynthesis). Consequently, previous studies have mainly focused on the relationships between dust seeds and heterotrophy. However, dust seeds are also found in green plants. This manuscript focuses on the seed ecology of the apparently autotrophic shrub Rhynchotechum discolor that produces dust seeds. Using time‐lapse photography, feeding experiments, and germination tests, we show that camel crickets effectively disperse the seeds of this autotrophic shrub. This is the first study to document insect‐mediated internal seed dispersal of an autotrophic plant in regions inhabited by terrestrial mammals, offering new insights into the evolutionary ecology of dust seeds.Summary Although angiosperms exhibit a wide range of seed sizes, the mechanisms driving these differences are poorly understood. The evolution of dust seeds, which contain minimal energy reserves, is traditionally linked to heterotrophy, in which external carbon sources are provided to the embryo or seedling. Dispersal by small animals may be another important but underexplored evolutionary driver of minute seed size. However, insect endozoochory has been documented only in the seeds of heterotrophic species and autotrophic species in New Zealand (i.e., in communities without native terrestrial mammals). Here, we investigate this seed dispersal mechanism in the Japanese shrub Rhynchotechum discolor (Gesneriaceae), which produces white berries with numerous tiny ellipsoid seeds, using time‐lapse photography, feeding experiments, and germination tests, particularly focusing on potential interactions with insect internal seed dispersers. Our time‐lapse photography indicated that camel crickets predominantly feed on fallen fruits of R. discolor. Field sampling revealed that camel crickets excreted numerous intact R. discolor seeds. Feeding experiments confirmed that some camel crickets excreted a high proportion of intact seeds, many of which successfully germinated into autotrophic seedlings. The present study provides the first evidence of insects acting as endozoochorous seed dispersers in fully autotrophic plants within regions inhabited by terrestrial mammals. Our findings suggest that orthopteran‐mediated seed dispersal is more widespread than previously thought, and that dust seeds can evolve from selective pressures beyond heterotrophy, specifically through insect‐mediated seed dispersal.