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Rapid advances in eradicating invasive species from islands are improving conservation outcomes in these biodiversity hotspots. However, recent conservation gains could be reversed not only by future invasions from non‐native species but also by future extinctions of native taxa, both of which may be facilitated by – or exacerbated by interactions among drivers of – global environmental change. We highlight relevant knowledge gaps that must be filled to reduce uncertainty about the ecological effects of future climate change. We use Aotearoa New Zealand as a case study of island ecosystems to demonstrate that in addition to sea‐level rise, most ecologically meaningful impacts of climate change on biodiversity responses are indirect and due to exacerbation of existing threats, including the impact of invasive species as well as the loss and fragmentation of habitat. We identify key topics where progress is needed to future‐proof conservation management for island ecosystems susceptible to the direct and indirect effects of climate change.

As ecological patterns are scale dependent, making decisions about sampling design critical. In the context of community assembly, many metrics have been developed to quantify species segregation and aggregation, of which the checkerboard metric (C-score) and the V-ratio are widely used. Using data that describe the spatial pattern of four species-rich, Mediterranean-climate, shrubland communities, we confirm the scale dependence of these metrics. At three of the four sites, we observed that the co-occurrence metrics monotonically increased across all the spatial grains we assessed; at the other site, the previously reported hump-shaped relationship between spatial grain and co-occurrence metrics was observed. The spatial grain at which measures of co-occurrence peaked varied across the plant communities and taxa and increased with exclusion of the less frequently sampled species. Inferences about community assembly using co-occurrence metrics must recognise their inherent scale dependence, and the inferential tools developed in spatial point pattern analysis may facilitate this task.

Sustaining ecosystem services (ES) is a key interest in the management of land use in multifunctional landscapes (i.e. ES that support ecosystem function and sustain human livelihoods). In making l...

Morphology and phenology influence plant-pollinator network structure, but whether they generate more stable pairwise interactions with higher pollination success remains unknown. Here we evaluate the importance of morphological trait matching, phenological overlap and specialisation for the spatio-temporal stability (measured as variability) of plant-pollinator interactions and for pollination success, while controlling for species' abundance. To this end, we combined a 6-year plant-pollinator interaction dataset, with information on species traits, phenologies, specialisation, abundance and pollination success, into structural equation models. Interactions among abundant plants and pollinators with well-matched traits and phenologies formed the stable and functional backbone of the pollination network, whereas poorly matched interactions were variable in time and had lower pollination success. We conclude that phenological overlap could be more useful for predicting changes in species interactions than species abundances, and that non-random extinction of species with well-matched traits could decrease the stability of interactions within communities and reduce their functioning.

Terrestrial plants and fire have interacted for at least 420 million years1. Whether recurrent fire drives plants to evolve higher flammability and what the evolutionary pattern of plant flammability is remain unclear2–7. Here, we show that phylogeny, the susceptibility of a habitat to have recurrent fires (that is, fire-proneness) and growth form are important predictors of the shoot flammability of 194 indigenous and introduced vascular plant species (Tracheophyta) from New Zealand. The phylogenetic signal of the flammability components and the variation in flammability among phylogenetic groups (families and higher taxonomic level clades) demonstrate that shoot flammability is phylogenetically conserved. Some closely related species, such as in Dracophyllum (Ericaceae), vary in flammability, indicating that flammability exhibits evolutionary flexibility. Species in fire-prone ecosystems tend to be more flammable than species from non-fire-prone ecosystems, suggesting that fire may have an important role in the evolution of plant flammability. Growth form also influenced flammability—forbs were less flammable than grasses, trees and shrubs; by contrast, grasses had higher biomass consumption by fire than other groups. The results show that shoot flammability of plants is largely correlated with phylogenetic relatedness, and high flammability may result in parallel evolution driven by environmental factors, such as fire regime. Fire has shaped plant life for millions of years, but flammability as an inherited trait has been difficult to discern. This Letter reveals several predictors in the evolution of plant flammability.

International audience; Despite many sectors of society striving for sustainability in environmental management, humans often fail to identify and act on the connections and processes responsible for social-ecological tipping points. Part of the problem is the fracturing of environmental management and social-ecological research into ecosystem domains (land, freshwater, and sea), each with different scales and resolution of data acquisition and distinct management approaches. We present a perspective on the social-ecological connections across ecosystem domains that emphasize the need for management reprioritization to effectively connect these domains. We identify critical nexus points related to the drivers of tipping points, scales of governance, and the spatial and temporal dimensions of social-ecological processes. We combine real-world examples and a simple dynamic model to illustrate the implications of slow management responses to environmental impacts that traverse ecosystem domains. We end with guidance on management and research opportunities that arise from this cross-domain lens to foster greater opportunity to achieve environmental and sustainability goals.

Long time-series of weather grids are fundamental to understanding how weather affects environmental or ecological patterns and processes such as plant distributions, plant and animal phenology, wildfires, and hydrology. Ideally such weather grids should be openly available and be associated with uncertainties so that users can understand any data quality issues. We present a History of Open Weather in New Zealand (HOWNZ) that uses climatological aided natural neighbour interpolation to provide monthly 1-km resolution grids of total rainfall, mean air temperature, mean daily maximum air temperature, and mean daily minimum air temperature across New Zealand from 1910 to 2019. HOWNZ matches the best available temporal extent and spatial resolution of any open weather grids that include New Zealand, and is unique in providing associated spatial uncertainty in appropriate units of measurement. The HOWNZ weather and uncertainty grids capture the dynamic spatial and temporal nature of the monthly weather variables and the uncertainty associated with the interpolation. We also demonstrate how to quantify and visualise temporal trends across New Zealand that recognise the temporal and spatial variation of uncertainties in the HOWNZ data. The HOWNZ data is openly available at https://doi.org/10.7931/zmvz-xf30 (Etherington et al., 2021).

1. Large animals provide crucial seed dispersal services, yet face continued threats and are susceptible to changes in landscape composition and configuration. Thus, there is a growing imperative to improve understanding of animal‐generated seed dispersal using models that incorporate spatial complexity in a realistic, yet tractable, way. 2. We developed a spatially explicit agent‐based seed dispersal model, with disperser movements informed by biotelemetry data, to evaluate how landscape composition and configuration affect seed dispersal patterns. We illustrated this approach for the world's second largest ratite, the emu (Dromaius novaehollandiae), a highly mobile generalist frugivore considered an important long‐distance disperser for many plant species across Australia. 3. When animal movement is unrestricted, model parameters related to seed gut passage largely determine seed dispersal kernels. However, as habitat loss and fragmentation increase, the extent of long‐distance dispersal events is reduced and seed shadows became progressively more aggregated. This effect is due to the emu not being able to move between disconnected parts of the landscape, with small changes in habitat structure causing decreased long‐distance dispersal. 4. We simulated seed dispersal patterns generated by three commonly used generic models of animal movement – unbiased and biased correlated random walks and Levy walks – to evaluate how different representations of movement affect estimations of animal movements and emergent seed dispersal patterns. Simulated movements informed by the emu biotelemetry data resulted in longer median seed dispersal distances than do the three generic models. 5. Synthesis. Changes in landscape composition and configuration can dramatically alter patterns of zoochorous seed dispersal as they influence animal movement. However, when models are used to simulate the patterns of seed dispersal, decisions about how animal movement is represented also affect estimates of seed dispersal.

Some extinctions have obvious drivers (e.g. over‐harvesting), while others can be less obvious and arise from multiple interacting factors. The extinction of the New Zealand grayling (Prototroctes oxyrhynchus) has been blamed on over‐fishing and predation by introduced trout, but these explanations fail to account for the species disappearance from isolated, uninvaded rivers. We investigated if source–sink dynamics, facilitated by P. oxyrhynchus's amphidromous dispersal habit, could account for the species’ rapid extinction. We created a database of P. oxyrhynchus sightings by surveying newspapers dating back to 1839, along with a review of traditional scientific literature. We used this database to update P. oxyrhynchus's known distribution map and inform sighting models to predict P. oxyrhynchus's extinction date. Finally, we implemented a meta‐population model to explore how source–sink dynamics could interact with off‐take (over‐fishing or predation) to drive extinction. Prototroctes oxyrhynchus was found across New Zealand, except the north of the North Island. Based on sightings methods, the earliest predicted extinction date was 1924, although the species may have persisted until 1972, later than previous estimates have suggested. In the absence of source–sink dynamics, relatively high levels of off‐take were sustainable (up to 30% per generation). When the species was modelled as a panmictic meta‐population including 5% sink habitats, the sustainable off‐take rate was reduced to as low as 5% per generation. Prototroctes oxyrhynchus was a widespread, abundant species that underwent rapid declines and ultimately went extinct. Previous attempts to explain this extinction have failed to account for the species extinction from isolated, pristine rivers. Our modelling shows that treating the species as a panmictic metapopulation and including source–sink dynamics rapidly increases the probability of extinction. We suggest that source–sink dynamics may be an important aspect of the population dynamics of amphidromous species and should be considered when managing taxa with similar dispersal habits.

Disruption of seed dispersal processes may affect plant population spatial structure. We used a spatial simulation model and an empirical case study to assess the conditions under which the loss of seed dispersers has a detectable effect on a species' spatial pattern. Our simulation experiments suggested that detecting spatial change following disperser loss will be difficult, except when rates of fruit removal are initially high and then completely disappear. To contextualize the simulation modeling, we used spatial point pattern analyses to characterize the spatial pattern of two large‐seeded species (Leucopogon nutans, a fire‐killed seeder shrub and Macrozamia riedlei, a long‐lived, resprouting cycad) in the jarrah (Eucalyptus marginata) forests of southwestern Australia. The plant species' primary disperser, the emu (Dromaius novaehollandiae), was absent from one of the sites we considered, but present at the other two. There was no detectable difference for either plant species in the strength of aggregation between sites with and without emu. However, even if disperser loss may not greatly affect local spatial structure for most plant species, it is likely to be important for long distance dispersal and genetic structuring of populations, so accurate characterization of the dispersal kernel is critical, especially in terms of plant emigration.

Global environmental change and humanity's growing demands for resources have generated concerns regarding how much pressure Earth systems can absorb without drastic, potentially irreversible consequences. In natural resource production systems, tipping points can generate immediate threats to human well-being. However, empirically exploiting conceptual tipping point models, and applying that learning to management has proven challenging. We argue that primary industries are characterized by a set of social and ecological features that predisposes them to tipping points and motivates studying them as a special class of social-ecological systems. Several primary industry features and feedback loops can explain why some resource systems face a high risk of tipping points, how social responses can affect the detection of early warnings, and how tipping points may cascade among primary industry subsystems. New understanding of resource resilience could be gained by complementing current research with a primary industry perspective. We discuss challenges and solutions for this research agenda.

Metapopulation persistence depends on connectivity between habitat patches. While emphasis has been placed on the spatial dynamics of connectivity, much less has been placed on its short‐term temporal dynamics. In many terrestrial and aquatic ecosystems, however, transient (short‐term) changes in connectivity occur as habitat patches are connected and disconnected due, for example, to climatic or hydrological variability. We evaluated the implications of transient connectivity using a network‐based metapopulation model and a series of scenarios representing temporal changes in connectivity. The transient loss of connectivity can influence metapopulation persistence, and more strongly autocorrelated temporal dynamics affect metapopulation persistence more severely. Given that many ecosystems experience short‐term and temporary loss of habitat connectivity, it is important that these dynamics are adequately represented in metapopulation models; failing to do so may yield overly optimistic‐estimates of metapopulation persistence in fragmented landscapes.

Wildfire is a widespread natural hazard that is expected to increase in areal extent, severity and frequency with ongoing changes in climate and land-use. One tool that has been used in an effort to reduce the damage caused by wildfires is green firebreaks: strips of low-flammability vegetation grown at strategic locations in the landscape. Green firebreaks are increasingly being recommended for wildfire management and have been implemented in many countries. The approach is particularly widely used in China, where more than 364,000 km of green firebreaks have been planted and a further 167,000 km are planned for construction before 2025. China is not only a world leader in the implementation of green firebreaks but has also led the way in testing the effectiveness of green firebreaks and in providing guidelines for green firebreak construction. However, most of this research has been reported in the non-English literature, and so is inaccessible to many readers. Here we review the extensive research on the construction and effectiveness of green firebreaks in China and examine how the lessons learned from this research could contribute to the effective implementation of green firebreaks globally. Chinese studies suggest that the ideal species for green firebreaks should meet trait requirements from three perspectives: ecological, silvicultural and economic. Green firebreaks with a multi-layered structure and a closed canopy have the potential to be an effective, long-term, biodiversity-friendly and low-cost tool for fire suppression, although they complement rather than replace other more traditional fire suppression approaches.

Sleeper populations of non-native species can remain at low abundance for decades before irrupting. For over a century, fallow deer ( Dama dama ) in the island state of Tasmania, Australia, remained at low abundance and close to the region in which they were released. Recently, there are indications the population has increased in abundance and distribution. Here, we spatially quantify the population change using a time series of annual spotlight counts from 1985 to 2019 (total of 5,761 counts). Next, we predict the potential for further range expansion, using global occurrences to characterise the species’ climatic niche, and remote-camera surveys (n = 3,225) to model fine-grained habitat suitability. Spotlight counts of fallow deer increased by 11.5% annually, resulting in a 40-fold increase from 1985 to 2019. The core distribution increased 2.9-fold during this 35-year period, and now spans c. 27% of Tasmania’s land area. Satellite populations have established in locations where farmed deer have escaped or been released, suggesting that humans have facilitated some of the range expansion via new introduction events. Based on climate and habitat suitability, our models predict that 56% of Tasmania is suitable under the current climate. This suggests range expansion is likely to continue unless the population is actively managed, which could include the eradication of satellite populations and containment of core populations. This case study cautions that despite over a century of slow population growth, sleeper populations of non-native species can abruptly increase.

Understanding the function of social networks can make a critical contribution to achieving desirable environmental outcomes. Social-ecological systems are complex, adaptive systems in which environmental decision makers adapt to a changing social and ecological context. However, it remains unclear how multiple social influences interact with environmental feedbacks to generate environmental outcomes. Based on national-scale survey data and a social-ecological agent-based model in the context of voluntary private land conservation, our results suggest that social influences can operate synergistically or antagonistically, thereby enabling behaviors to spread by two or more mechanisms that amplify each other’s effects. Furthermore, information through social networks may indirectly affect and respond to isolated individuals through environmental change. The interplay of social influences can, therefore, explain the success or failure of conservation outcomes emerging from collective behavior. To understand the capacity of social influence to generate environmental outcomes, social networks must not be seen as ‘closed systems’; rather, the outcomes of environmental interventions depend on feedbacks between the environment and different components of the social system.

Plant flammability varies across species, but the evolutionary basis for this variation is not well understood. Phylogenetic analysis of interspecific variation in flammability can provide insights into the evolution of plant flammability. We measured four components of flammability (ignitability, sustainability, combustibility and consumability) to assess the shoot-level flammability of 21 species of Dracophyllum (Ericaceae). Using a macroevolutionary approach, we explored phylogenetic patterns of variation in shoot-level flammability. Shoot-level flammability varied widely in Dracophyllum. Species in the subgenus Oreothamnus had higher flammability and smaller leaves than those in the subgenus Dracophyllum. Shoot flammability (ignitability, combustibility and consumability) and leaf length showed phylogenetic conservatism across genus Dracophyllum, but exhibited lability among some closely related species, such as D. menziesii and D. fiordense. Shoot flammability of Dracophyllum species was negatively correlated with leaf length and shoot moisture content, but had no relationship with the geographic distribution of Dracophyllum species. Shoot-level flammability varied widely in the genus Dracophyllum, but showed phylogenetic conservatism. The higher flammability of the subgenus Oreothamnus may be an incidental or emergent property as a result of the evolution of flammability-related traits, such as smaller leaves, which were selected for other functions and incidentally changed flammability.

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and drier than average conditions across the globe. Disturbances in protected areas are smaller and more complex in shape compared to their surroundings affected by human land use. This signal disappears in areas with high recent natural disturbance activity, underlining the potential of climate-mediated disturbance to transform forest landscapes., Climate change may impact forest disturbances, though local variability is high. Here, Sommerfeld et al. show that disturbance patterns across the temperate biome vary with agents and tree traits, yet large disturbances are consistently linked to warmer and drier than average conditions.