Biodiversity Threats Research Articles

Assessing long‐term effects of artificial light at night on insects: what is missing and how to get there

Abstract Widespread and significant declines of insect population abundances and biomass are currently one of the most pressing issues in entomology, ecology and conservation biology. It has been suggested that artificial light at night is one major driver behind this trend. Recent advances in the gathering and analysis of long‐term data sets of insect population and biomass trends, however, have mostly focused on the effects of climate change and agricultural intensification. We posit here that adequate assessment of artificial night at light that would be required to evaluate its role as a driver of insect declines is far from trivial. Currently its implementation into entomological monitoring programmes and long‐running ecological experiments is hampered by several challenges that arise due to (i) its relatively late appearance as a biodiversity threat on the research agenda and (ii) the interdisciplinary nature of the research field where biologists, physicists and engineers still need to develop a set of standardised assessment methods that are both biologically meaningful and easy to implement. As more studies that address these challenges are urgently needed, this article aims to provide a short overview of the few existing studies that have attempted to investigate longer‐term effects of artificial light at night on insect populations. To improve the quality and relevance of studies addressing artificial light at night and its effect on insects, we present a set of best practise recommendations where this field needs to be heading in the coming years and how to achieve it.

Spatio-temporal remotely sensed indices identify hotspots of biodiversity conservation concern

Over the course of a year, vegetation and temperature have strong phenological and seasonal patterns, respectively, and many species have adapted to these patterns. High inter-annual variability in the phenology of vegetation and in the seasonality of temperature pose a threat for biodiversity. However, areas with high spatial variability likely have higher ecological resilience where inter-annual variability is high, because spatial variability indicates presence of a range of resources, microclimatic refugia, and habitat conditions. The integration of inter-annual and spatial variability is thus important for biodiversity conservation. Areas where spatial variability is low and inter-annual variability is high are likely to limit resilience to disturbance. In contrast, areas of high spatial variability may be high priority candidates for protection. Our goal was to develop spatio-temporal remotely sensed indices to identify hotspots of biodiversity conservation concern. We generated indices that capture the inter-annual and spatial variability of vegetation greenness and land surface temperature and integrated them to identify areas of high, medium, and low biodiversity conservation concern. We applied our method in Argentina (2.8 million km2), a country with a wide range of climates and biomes. To generate the inter-annual variability indices, we analyzed MODIS Enhanced Vegetation Index (EVI) and Land Surface Temperature (LST) time series from 2001 to 2018, fitted curves to obtain annual phenological and seasonal metrics, and calculated their inter-annual variability. To generate the spatial variability indices, we calculated standard deviation image texture of Landsat 8 EVI and LST. When we integrated our inter-annual and spatial variability indices, areas in the northeast and parts of southern Argentina were the hotspots of highest conservation concern. High inter-annual variability poses a threat in these areas, because spatial variability is low. These are areas where management efforts could be valuable. In contrast, areas in the northwest and central-west are where protection should be strongly considered because the high spatial variability may confer resilience to disturbance, due to the variety of conditions and resources within close proximity. We developed remotely sensed indices to identify hotspots of high and low conservation concern at scales relevant to biodiversity conservation, which can be used to target management actions in order to minimize biodiversity loss.

Living at the Edge: Increasing Stress for Plants 2–13 Years After the Retreat of a Tropical Glacier

Rapid warming is a major threat for the alpine biodiversity but, at the same time, accelerated glacial retreat constitutes an opportunity for taxa and communities to escape range contraction or extinction. We explored the first steps of plant primary succession after accelerated glacial retreat under the assumption that the first few years are critical for the success of plant establishment. To this end, we examined plant succession along a very short post-glacial chronosequence in the tropical Andes of Ecuador (2–13 years after glacial retreat). We recorded the location of all plant individuals within an area of 4,200 m2divided into plots of 1 m2. This sampling made it possible to measure the responses of the microenvironment, plant diversity and plants traits to time since the glacial retreat. It also made it possible to produce species-area curves and to estimate positive interactions between species. Decreases in soil temperature, soil moisture, and soil macronutrients revealed increasing abiotic stress for plants between two and 13 years after glacial retreat. This increasing stress seemingly explained the lack of positive correlation between plant diversity and time since the glacial retreat. It might explain the decreasing performance of plants at both the population (lower plant height) and the community levels (lower species richness and lower accumulation of species per area). Meanwhile, infrequent spatial associations among plants indicated a facilitation deficit and animal-dispersed plants were almost absent. Although the presence of 21 species on such a small sampled area seven years after glacial retreat could look like a colonization success in the first place, the increasing abiotic stress may partly erase this success, reducing species richness to 13 species after 13 years and increasing the frequency of patches without vegetation. This fine-grain distribution study sheds new light on nature's responses to the effects of climate change in cold biomes, suggesting that faster glacial retreat would not necessarily result in accelerated plant colonization. Results are exploratory and require site replications for generalization.

Diversity and Threats of Avifauna in Cheleleka Wetland, Central Rift Valley of Ethiopia

This study was conducted in Cheleleka Wetland, Central Rift Valley of Ethiopia to assess Species diversity and threats of aviafuana from August to February 2019. Data were analysed by using Simpson’s and Shannon-Weiner Index in analysing biodiversity indices. One way ANOVA was applied for analysis of the effect of season on the composition and abundance of species. Questionnaire surveys, key informant interviews and focus group discussion were also used to determine the threats of avifauna in the study area. The result indicated that 49 avian species record under 21 families and 10 orders during both the wet and dry seasons. The Shannon-Weiner diversity index shown that highest bird species diversity (H’=3.42) was recorded during wet season. Over grazing, agricultural expansion, settlement and sand extraction were the major avifaunal threats in the wetland. The result suggests that the need to conserve the avifauna through the conservation of their habitats by creating awareness to the local people and it will enable to decrease biodiversity threats.

CITES and beyond: Illuminating 20 years of global, legal wildlife trade

Nature has the potential to provide wide-ranging economic contributions to society – from ecosystem services to providing income to communities via fair trade of resources. Unsustainable trade in wildlife, however, threatens biodiversity and its ability to support communities and a functioning planet. It is therefore important to have clear systems in place for tracing traded wildlife. Monitoring legal wildlife trade in all species is as important as it is for trade in protected species, since flows of the legal trade correlate with, and provide cover for, illegally traded wildlife. The majority of wildlife trade research is focused on species listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The concurrent, considerably larger legal wildlife trade in both CITES and non-CITES-listed species, however, remains unexamined – despite the fact that if mismanaged, it can lead to over-exploitation. Here we analyzed 20 years of data from the UN Comtrade database, aiming to detail the scale, composition, and trends across all taxa of wildlife traded legally, and to indicate opportunities for improvement. From 1997 to 2016 the value of this trade totaled between US$2.9 and 4.4 trillion. Of this, $2.9 trillion wildlife was traded under “specific” codes that specify taxonomic Order and below, while around $1.4 trillion was traded under “broad” codes that declare wildlife to taxonomic Class and above. The top 10 trading nations/territories accounted for 51.4% of the total value of wildlife traded. The top commercial categories for wildlife trade were seafood (82%), furniture (7%), and fashion (furs and hides) (6%). In these three major categories, vague commodity codes such as “Fish”, “Tropical wood”, and “Other furs” were used to declare 23%, 24% and 26% of items traded, respectively – despite encompassing thousands of species. This lack of granularity imperils biodiversity as trade cannot be comprehensively monitored. We recommend a review of what species are traded under these broad code descriptions, and a distillation of codes to taxonomic Family or Genus level in the next HS Code review period, particularly in the pet, traditional Chinese medicine and furniture categories. In addition, interdisciplinary research into legal wildlife trade should be increased to provide forensic, policy, economic and social solutions to improve trade management.

Non-indigenous macrophytes in Central Mediterranean ports, marinas and transitional waters: Origin, vectors and pathways of dispersal

Non-indigenous species are confirmed to be among the biggest threats for marine biodiversity. Among them, non-indigenous macrophytes (NIM) are well known to have local negative effects, especially in coastal ecosystems. Since transitional waters (TWs), ports and also marinas are recognized as very vulnerable coastal ecosystems, greatly subjected to biological invasions, the present study analysed the available scientific literature on NIM in such areas in the Central Mediterranean Sea (CMED), in the period 1970–2019. The analysis underlined that 27 NIM were recorded in CMED TWs, marinas and ports. Around 37% of them (10 species) are marked as invasive, while about 11% (3 species) are considered as potentially invasive. Maricultural activities resulted the key vector of introduction, while the primary pathway of NIM dispersion is related to maritime activities. The paper also discusses why in CMED TWs, marinas and ports, currently, less NIM were detected than in similar Adriatic areas.

Effects of long-term floodplain disconnection on multiple facets of lake fish biodiversity: Decline of alpha diversity leads to a regional differentiation through time

Hydrological disconnection is increasingly threatening biodiversity in river floodplain ecosystems worldwide, but studies reporting long-term change of aquatic biodiversity in relation to floodplain disconnection are seldom, especially from multifaceted biodiversity perspectives. Here, we examined how loss of river-lake connectivity affected multifaceted (taxonomic, functional and phylogenetic) alpha and beta diversity of fish assemblages in 11 Yangtze River floodplain lakes over the past 70 years. We found that all three facets of alpha diversity significantly decreased through time, but the decrease rate was highest (31.4%) in taxonomic richness, second in functional (26.4%) and lowest in phylogenetic facet (4.7%). Nevertheless, taxonomic, functional and phylogenetic structures of fish fauna all exhibited differentiation. The taxonomic and phylogenetic differentiations were due to the joint increases in their turnover and nestedness-resultant component, whereas the functional differentiation was mainly driven by the increase in its turnover component. Such distinct results were because of the imbalanced extirpations of fish species (especially from species-poor orders and families) in disconnected lakes and connected lakes. With few exceptions of strong correlations between changes in taxonomic dissimilarities and phylogenetic dissimilarities, we generally found weak correlations between changes in different facets of both alpha and beta diversity. This discrepancy highlights that measuring different biodiversity facets offer distinct information about biodiversity dynamics and can enhance our ability to detect and evaluate the impacts of floodplain disconnection on biodiversity. We therefore recommend an integrative approach embracing taxonomic, functional and phylogenetic diversity is essential to effective biodiversity assessment and conservation in large river floodplains.

Hidden below‐ground plant diversity buffers against species loss during land‐use change in species‐rich grasslands

AbstractQuestionsTheory suggests that while plant diversity of grasslands decreases in response to increased competition for light, many plant species persist below‐ground even in the temporary absence of shoots. Thus, we hypothesized that below‐ground, diversity is less affected by increased competition during land‐use change compared to above‐ground.LocationSpecies‐rich, oligotrophic grasslands in the Železné hory Mts, eastern Bohemia, Czech Republic.MethodsWe quantified above‐ and below‐ground plant richness (roots and rhizomes, seed and bud bank) in grasslands subjected to seven years of experimental abandonment and fertilization. We used conventional species identification to measure richness above‐ground and 454 sequencing of the chloroplast trnL (UAA) gene to measure richness of roots and rhizomes; additionally, we used the shoot emergence method to measure soil seed and bud bank richness.ResultsWhile above‐ground richness decreased with abandonment and fertilization, below‐ground richness remained less affected or even increased compared to the control (traditional mowing). Overall, compared to above‐ground the proportion of plant species found only below‐ground as roots and rhizomes increased, particularly in the abandonment with fertilization treatment.ConclusionsBelow‐ground plant diversity could potentially buffer against biodiversity losses during short‐term land‐use change. Our findings highlight that measuring the complete plant species diversity improves our understanding of processes that underlie plant diversity and coexistence and refine predictions of vegetation responses to biodiversity threats.

Increasing protected area coverage mitigates climate-driven community changes

Climate change has ubiquitous impacts on ecosystems and threatens biodiversity globally. One of the most recognized impacts are redistributions of species, a process which can be hindered by habitat degradation. Protected areas (PAs) have been shown to be beneficial for preserving and reallocating species occurrences under climate change. Yet, studies investigating effects of PA networks on species' range shifts under climate change remain scarce. In theory, a well-connected network of PAs should promote population persistence under climate change and habitat degradation. To study this, we evaluated the effects of PA coverage on avian communities in Finland between two study periods of 1980–1999 and 2000–2015. Climate-driven community impacts were investigated by using community temperature index (CTI). We used linear models to study the association of PA coverage and the CTI changes in southern, central and northern Finland. In northern and central Finland, higher PA coverage was associated with lower changes in CTI and 45% PA coverage in northern and 13% in central Finland corresponded with complete mitigation of CTI increase. These results indicate that higher PA coverage strongly increases community resilience to warming climate. However a similar association between PA coverage and changes in CTI was not apparent in southern Finland. The PA coverage in southern Finland was much lower than in the two other sections and thus, may be too sparse to favour community resilience against climate change. The results provide empirical evidence for the international need to rapidly expand PA networks and halt biodiversity loss.

Responses of stream zooplankton diversity metrics to eutrophication and temporal environmental variability in agricultural catchments

Eutrophication of rivers and streams in agricultural lands is one of the main threats for biodiversity and ecosystem functions. This study was focused on seven subtropical streams where agriculture is the predominant land use. We tested the hypothesis that (i) eutrophication causes a decrease in taxonomic and functional diversity of zooplankton, leading to potential consequences for the ecosystem integrity. Furthermore, given that the temporal variability in the environmental conditions of each stream may influence the species sorting mechanisms, we also hypothesized that (ii) streams with higher temporal environmental variability have greater taxonomic and functional alpha (α) and temporal beta (βt) diversity measures regardless of the trophic state. Thus, we characterized the streams according to their trophic state and analyzed the zooplankton composition, α and βt by using taxonomic and functional perspectives. We found differences in the zooplankton composition between mesotrophic and eutrophic streams. However, eutrophic streams supported similar taxonomic and functional α diversity and similar taxonomic βt diversity to mesotrophic ones. These results were mainly explained by the occurrence of rare species occupying different temporal niches in eutrophic systems. On the contrary, functional βt diversity was lower in the eutrophic streams, being nestedness the ecological mechanisms underlying the variability in the zooplankton functional groups. Streams with higher temporal environmental variability supported greater α taxonomic diversity. However, the βt diversity metrics showed no correlation with the environmental variability, suggesting that the environmental filters of the studied systems were the overriding determinants of species turnover. Our study suggests that both taxonomic and functional perspectives should be considered to improve our knowledge on the biotic responses to environmental changes. Also, among all metrics analyzed on the zooplankton community, functional βt diversity was the most sensitive indicator of the eutrophication impact.

Prioritising conservation actions for biodiversity: Lessening the impact from habitat fragmentation and climate change

The interacting impacts of habitat fragmentation and climate change present a substantial threat for biodiversity, constituting a ‘deadly anthropogenic cocktail’. A range of conservation actions has been proposed to allow biodiversity to respond to those environmental changes. However, determining the relative effectiveness of these actions has been hampered by incomplete evidence. Empirical studies have provided important insights to inform conservation, but the challenge of considering multiple actions at large spatial and temporal scales is considerable. We adopt an individual-based modelling approach to qualitatively assess the effectiveness of alternative conservation actions in facilitating range expansion and patch occupancy for eight virtual species. We test actions to: (i) improve the quality of existing habitat patches, (ii) increase the permeability of the surrounding matrix, (iii) restore degraded habitat, (iv) create new habitat patches to form stepping-stones or (v) create new habitat to enlarge existing habitat patches. These actions are systematically applied to six real landscapes of the UK, which differ in their degree of habitat fragmentation and availability. Creating new habitat close to existing patches typically provides the strongest benefits for both range expansion and patch occupancy across species and landscapes. However, some landscapes may be so degraded that even under unrealistically high levels of management action, species' performances cannot be rescued. We identify that it is possible to develop a triage of conservation actions at the landscape, species and investment level, thereby providing timely evidence to inform action on the ground to lessen the hangover from the deadly anthropogenic cocktail.

Reliable estimates of wild boar populations by nocturnal distance sampling

The wild boar is one of the most invasive species among large mammals in both its native and introduced ranges. This species represents a main threat for crops and biodiversity and a pest for the pig industry due to the rapid expansion of the African swine fever. Because of its peculiar life history traits, population control programmes and recreational hunting are usually unable to effectively reduce the number of wild boars. Therefore, a reliable approach based on appropriate, cost‐effective, monitoring methodologies is urgently required. Effective monitoring should adopt effective sampling strategies, otherwise the detection of population trends can be erroneous and resulting in a mismatch of appropriate management actions. First, we review the status‐of‐the‐art of wildlife monitoring with a special focus on wild boar and feral pigs. Then, we show that nocturnal distance sampling, carried out using thermal cameras, can be an effective monitoring technique for wild boar population assessment regardless of the characteristics of the sampled area. Using data from multiple surveys performed in four study areas in Italy, characterised by contrasting topography, habitats and level of environmental visibility, we found that the estimate of precision is generally good and almost independent of landscape conditions. A simple method to estimate visibility, which may empirically help wildlife managers to design effective nocturnal distance sampling surveys, is proposed. The bias of our population estimates is evaluated using simulations showing that in some areas the estimate is unbiased, while in others there is the tendency towards a negative bias. Based on reported results, we provide guidelines to perform nocturnal distance sampling of wild boar populations.

How protected are marine protected areas: A case study of tributyltin in Latin America

Protected areas (PAs) are dedicated and managed to achieve long-term conservation of nature with associated ecosystem services and cultural values. However, few studies have assessed contamination/pollution, one of the top five biodiversity threats, within these areas. In fact, more than 100,000 molecules used in consumer goods are potentially affecting over 250,000 protected areas distributed worldwide. As a result, chemical appraisal within PAs require specific approaches to be feasible. Herein, an approach for assessment of contamination in marine protected areas (MPAs) spread over large continental and/or global areas was proposed and tested using, as a case study, the impact of tributyltin (TBT) within Latin America. This approach included area delimitation, bibliographic survey, construction of attribute tables, data insertion in a Geographic Information System, overlapping with worldwide shapefiles of PAs, identification of affected PAs and evaluation of impacts using the outcomes against specific environmental quality guidelines/directives. A total of 259 records of TBT occurrence and/or its biological effect within 53 marine protected areas (including biosphere reserves, Ramsar sites and National parks) were gathered. Among affected species, were recorded 18 gastropods exhibiting imposex. In addition, 6 bivalves, 1 crustacean, and 3 fish species presenting TBT residues in tissues were seen in MPAs from Brazil, Argentina, Ecuador, Peru, Chile and Venezuela. Since levels of TBT recorded in several studied MPAs were enough do induce deleterious biological responses over marine biota, it was clear that conservancy goals of some “protected” areas are under threat. Considering that only TBT exposure was appraised, and these areas are likely to be concomitantly exposed to other classes of contaminants, the actual scenario can be even more frightening. Although initially applied as a TBT case study, the present approach enables an overview for other chemicals within protected areas worldwide.

Riverine plastic pollution from fisheries: Insights from the Ganges River system

Abandoned, lost or otherwise discarded fishing gear represents a substantial proportion of global marine plastic pollution and can cause significant environmental and socio-economic impacts. Yet little is known about its presence in, and implications for, freshwater ecosystems or its downstream contribution to plastic pollution in the ocean. This study documents fishing gear-related debris in one of the world's largest plastic pollution contributing river catchments, the Ganges. Riverbank surveys conducted along the length of the river, from the coast in Bangladesh to the Himalaya in India, show that derelict fishing gear density increases with proximity to the sea. Fishing nets were the main gear type by volume and all samples examined for polymer type were plastic. Illegal gear types and restricted net mesh sizes were also recorded. Socio-economic surveys of fisher communities explored the behavioural drivers of plastic waste input from one of the world's largest inland fisheries and revealed short gear lifespans and high turnover rates, lack of appropriate end-of-life gear disposal methods and ineffective fisheries regulations. A biodiversity threat assessment identified the air-breathing aquatic vertebrate species most at risk of entanglement in, and impacts from, derelict fishing gear; namely species of threatened freshwater turtle and otter, and the endangered Ganges river dolphin. This research demonstrates a need for targeted and practical interventions to limit the input of fisheries-related plastic pollution to this major river system and ultimately, the global ocean. The approach used in this study could be replicated to examine the inputs, socio-economic drivers and ecological impacts of this previously uncharacterised but important source of plastic pollution in other major rivers worldwide.

Covid-19 Outbreak, Timber Production, and Livelihoods in Nepal

The study assesses the likely consequences of COVID-19 in the forest sector of Nepal, focusing on timber production and rural livelihoods. The study conducted telephone interviews along with a review of the secondary source of information and consultations. The timber production in 2020 is likely to decrease by 80% compared to previous years, resulting in a monetary loss of NRs 647.0 million. Furthermore, local community will lose 147,447 days of employment, amounting NRs 117.9 million. This will make livelihoods of the people more vulnerable. Returning of youths from abroad can further escalate biodiversity threats. Timber import is likely to increase in the country, thus impacting on local level employment opportunities. Both long-term and short-term strategies are necessary to revive the timber production and rural livelihoods, where priority should be on increasing investment in the forestry sector. However, public-sector investment is declining. Hence there is a need to expand conservation finance portfolios to incentivise rural people on timber production and achieve synergies between conservation and livelihood outcomes.

Focus and social contagion of environmental organization advocacy on Twitter.

Agriculture, overexploitation, and urbanization remain the major threats to biodiversity in the Anthropocene. The attention these threats garner among leading environmental nongovernmental organizations (eNGOs) and the wider public is critical in fostering the political will necessary to reverse biodiversity declines worldwide. I analyzed the advocacy of leading eNGOs on Twitter by scraping account timelines, screening content for advocacy relating to biodiversity threats and, for prevalent threats, further screening content for positive and negative emotional language with a sentiment lexicon. Twitter advocacy was dominated by the major threats of climate change and overexploitation and the minor threat of plastic pollution. The major threats of agriculture, urbanization, invasions, and pollution were rarely addressed. Content relating to overexploitation and plastic pollution was more socially contagious than other content. Increasing emotional negativity further increased social contagion, whereas increasing emotional positivity did not. Scientists, policy makers, and eNGOs should consider how narrowly focused advocacy on platforms like Twitter will contribute to effective global biodiversity conservation.

Renewable energy production will exacerbate mining threats to biodiversity

Renewable energy production is necessary to halt climate change and reverse associated biodiversity losses. However, generating the required technologies and infrastructure will drive an increase in the production of many metals, creating new mining threats for biodiversity. Here, we map mining areas and assess their spatial coincidence with biodiversity conservation sites and priorities. Mining potentially influences 50 million km2 of Earth’s land surface, with 8% coinciding with Protected Areas, 7% with Key Biodiversity Areas, and 16% with Remaining Wilderness. Most mining areas (82%) target materials needed for renewable energy production, and areas that overlap with Protected Areas and Remaining Wilderness contain a greater density of mines (our indicator of threat severity) compared to the overlapping mining areas that target other materials. Mining threats to biodiversity will increase as more mines target materials for renewable energy production and, without strategic planning, these new threats to biodiversity may surpass those averted by climate change mitigation.

Functional genetic diversity of domestic and wild American mink (Neovison vison).

The release of domestic organisms to the wild threatens biodiversity because the introduction of domestic genes through interbreeding can negatively impact wild conspecifics via outbreeding depression. In North America, farmed American mink (Neovison vison) frequently escape captivity, yet the impact of these events on functional genetic diversity of wild mink populations is unclear. We characterized domestic and wild mink in Ontario at 17 trinucleotide microsatellites located in functional genes thought to be associated with traits affected by domestication. We found low functional genetic diversity in both mink types, as only four of 17 genes were variable, yet allele frequencies varied widely between captive and wild populations. To determine whether allele frequencies of wild populations were affected by geographic location, we performed redundancy analysis and spatial analysis of principal components on three polymorphic loci (AR, ATN1 and IGF‐1). We found evidence to suggest domestic release events are affecting the functional genetic diversity of wild mink, as sPCA showed clear distinctions between wild individuals near mink farms and those located in areas without mink farms. This is further substantiated through RDA, where spatial location was associated with genetic variation of AR, ATN1 and IGF1.

The ghost of disturbance past: long-term effects of pulse disturbances on community biomass and composition.

Current global change is associated with an increase in disturbance frequency and intensity, with the potential to trigger population collapses and to cause permanent transitions to new ecosystem states. However, our understanding of ecosystem responses to disturbances is still incomplete. Specifically, there is a mismatch between the diversity of disturbance regimes experienced by ecosystems and the one-dimensional description of disturbances used in most studies on ecological stability. To fill this gap, we conducted a full factorial experiment on microbial communities, where we varied the frequency and intensity of disturbances affecting species mortality, resulting in 20 different disturbance regimes. We explored the direct and long-term effects of these disturbance regimes on community biomass. While most communities were able to recover biomass and composition states similar to undisturbed controls after a halt of the disturbances, we identified some disturbance thresholds that had long-lasting legacies on communities. Using a model based on logistic growth, we identified qualitatively the sets of disturbance frequency and intensity that had equivalent long-term negative impacts on experimental communities. Our results show that an increase in disturbance intensity is a bigger threat for biodiversity and biomass recovery than the occurrence of more frequent but less intense disturbances.

Off-centring empire in the Anthropocene: towards multispecies intimacies and nonhuman agents of survival

ABSTRACT This paper examines colonial legacies in human-nonhuman relations to off-centre empire in the Anthropocene. Imperial methods of collecting, preserving and displaying nature profoundly shaped species perception, which in turn affected the scientific attention and ecological relevance a species was granted. In particular, I reflect on the category of invasibility to show how empire sanctioned the mobility of specific population groups and animal species as border-crossing. This further shows how speciesist logics served to extend, maintain and legitimize imperial power. This analysis is relevant in the Anthropocene where invasibility is mobilised to police movement in the context of increased human and nonhuman migration. Further, I discuss how invasibility is considered as one of main threats for biodiversity, which may misdirect conservation efforts. Overall, the article examines the potential in human-nonhuman encounters to challenge colonial legacies. Based on an ethnographic example of multispecies homemaking with species considered invasive in (hetero)normative modes of intimacy and domesticity, I argue that colonial legacies of racialized, gendered and speciesist hierarchies can be disturbed by human-nonhuman relations of companionship, care and interdependence. Finally, I scale-up the analysis to the landscape, by tracing the transformation of a former imperial wasteland in Vienna’s peripheral South from being perceived as economically and aesthetically worthless to a natural monument. Attending to multispecies entanglements is key here to understand the transformative process that led to the recovery of this wasteland. Here I off-centre empire by challenging anthropocentric narrations of how landscape transforms in favour of a narration that re-centres nonhuman agency. I argue that stories of wasteland recovery guided by nonhuman animals are crucial due to the increase in industrial wasteland and environmental degradation in the Anthropocene.