Allocation of water specifically to the environment (often dubbed ‘environmental water’ or ‘environmental flows’) can be contentious within government, among irrigators and between community members. The reduction in supply of fresh water has led to questions surrounding the efficiencies and ecological value of securing these adequate flows for waterways. This literature review examines the evidence on these perceptions of environmental water allocations, focusing foremost on general public, irrigator, Indigenous and decision-maker perspectives. Existing studies are predominantly in Global North areas such as Australia, Canada and the USA. Two themes featured strongly in the papers: the importance of personal values in the acceptance of environmental water and the perception of fairness in environmental water allocation processes. Although the research area has been expanding, there is still limited representation in types of study, disciplinary backgrounds and study locations, and as such many research opportunities remain.

The intrinsic complexity, variety of concepts and numerous ways to quantify landscape heterogeneity (LH) may hamper a better understanding of how its components relate to ecological phenomena. Our study is the first to synthesize understanding of this concept and to provide the state of the art on the subject based on a comprehensive systematic literature review of 661 articles published between 1982 and 2019. Definitions, terminologies and measurements of LH were diverse and conflicting. Most articles (534 out of 661) did not provide any definition for LH, and we found great variation among the studies that did. According to our review, only 10 studies measured the effects of different land-cover types on biotic or abiotic processes (functional LH). The remaining 651 studies measured physical attributes of the landscape without mentioning that different land-cover types may impact biotic and abiotic processes differently (structural LH). The metrics most frequently used to represent LH were the Shannon diversity index and proportion of land-cover type. Most metrics used as proxies of LH also coincided with those used to represent non-heterogeneity metrics, such as fragmentation and connectivity. We identify knowledge gaps, indicate future perspectives and propose guidelines that should be addressed when researching LH.

Unsustainable hunting threatens biodiversity in the tropics through the removal of key seed-dispersing frugivorous primates. Traditionally, hunting in the Amazon Basin was managed through hunter territoriality, with the threat of social sanctions for overexploitation. We examined hunter territoriality and differential prey selection as alternative hypotheses to central-place foraging. Territoriality occurred beyond common hunting grounds, which were on major rivers and immediately surrounding the community. Hunters displayed selectivity in prey choice, with 50% of hunters not hunting primates. The combination of hunter territoriality and differential prey selection means that over 22% of the hunted area of the Sucusari river basin could be considered primate refuge. Of the remaining hunted area, 16% was hunted relatively little by primate hunters. We suggest that the combination of territoriality and selection against primates creates refuges, mitigating the effects of sustained hunting pressure and contributing to the conservation of these species.

One of the multiple threats to protected areas worldwide, invasive plant species have the potential to decrease biodiversity and ecosystem function. We studied changes in infestation by two widespread invasive plant species – Chromolaena odorata and Mikania micrantha – in India’s Manas National Park, a critical conservation site for threatened flora and fauna. Based on field surveys in 2011 and 2019, we found that C. odorata and M. micrantha were present in most of the sampled plots and had newly invaded over 20% of the plots. However, the abundance of M. micrantha decreased in 45% of the plots while C. odorata increased in >50% of the plots. We used a decision tree-based regression with environmental variables as predictors to generate the distribution, abundance and invasion risk maps of the two species. Among environmental variables, road proximity and fire frequency had the strongest influences, respectively, on C. odorata and M. micrantha. Invaded quadrats exhibited lower native-plant diversity than non-invaded quadrats, and C. odorata specifically had a strong negative association with native-plant community structure. These invasive species have increased their range and abundance, and our predicted invasion risk maps indicate the areas where management intervention is urgently needed.

Loss of local biodiversity resulting from abrupt environmental change is a significant environmental problem throughout the world. Extinctions of plants are particularly important yet are often overlooked. Drawing from a case in Hawai‘i, a global hotspot for plant and other extinctions, we demonstrate an effort to better understand and determine priorities for the management of an endangered plant (‘Ihi makole or Portulaca sclerocarpa) in the face of rapid and extreme environmental change. Volcanic heat emissions and biological invasions have anecdotally been suggested as possible threats to the species. We integrated P. sclerocarpa outplanting with efforts to collect geological and ecological data to gauge the role of elevated soil temperatures and invasive grasses in driving P. sclerocarpa mortality and population decline. We measured soil temperature, soil depth, surrounding cover and P. sclerocarpa survivorship over three decades. The abundance of wild P. sclerocarpa decreased by 99.7% from the 1990s to 2021. Only 51% of outplantings persisted through 3–4 years. Binomial regression and structural equation modelling revealed that, among the variables we analysed, high soil temperatures were most strongly associated with population decline. Finding the niche where soil temperatures are low enough to allow P. sclerocarpa survival but high enough to limit other agents of P. sclerocarpa mortality may be necessary to increase population growth of this species.

Government conservation measures will always depend on public support. While more has been learnt about which species the public values and which conservation measures are socially acceptable, less is known about the criteria that the public thinks government should consider when making conservation investment decisions. This study uses a stated preference best–worst scaling method to gauge the views of a sample of the Australian public on what they think government should consider when allocating funding to threatened species conservation. We found that the three most important factors were the risk that a species might become extinct, the likelihood that a conservation intervention might be effective and the risk of unintended consequences for other species that could potentially arise if the measure was implemented. Costs of conservation measures and the degree to which the society accepts these costs were considered much less important. The latter aspect was consistent with the high level of trust that respondents placed in the judgement of experts and scientists concerning threatened species conservation. We conclude that the Australian Government has a societal mandate to spend more money on threatened species conservation, provided that there is little risk and that it is backed up by science.

The analysis of conservation narratives primarily resides in the methods and techniques of social sciences, focusing mainly on uncovering advocacy versus critical lines of thought in the complex mosaic of arguments around institutional actors and the public. Researchers have previously proposed an archetypal scheme in which the core conservation narratives and their conceptual interrelations are classified. This report explores the feasibility of coupling such a traditional method with techniques emanating from quantitative linguistics, network analysis and bibliometry. The neologic metaphor of the Anthropause is purposely added to long-established narratives to examine its potential effects on the conservation narratives landscape. The results show that this metaphor reorganizes the mentally constructed connections between flag narratives and symbolic lexical units.

The energy needs of the human population inevitably affect natural environments, but the effects on wildlife of human modifications of habitat specifically for geothermal projects are scarcely known. Through acoustic monitoring, we quantified at Proyecto Geotérmico Las Pailas II, Guanacaste, Costa Rica, the impact of forest openings on the diversity and community composition of aerial insectivorous bats. Our data revealed that artificial clearing causes a border effect, an environment where the diversity of species and activity levels of insectivorous bats increase with respect to other habitats analysed. We discuss that, due to the combination of environmental properties and resource availability variables of the border habitats, in addition to the acoustic abilities of the bat species detected, borders represent transitional spaces where species adapted to uncluttered and background-cluttered spaces can easily commute and forage. The artificial clearings created by the geothermal project had a positive effect on aerial insectivorous bat species; however, this pattern cannot be assumed for other organisms within the area. Therefore, we highlight the importance of quantifying the influence of energy-extracting projects on biodiversity metrics and the use of this information to make informed decisions regarding managing and conserving natural resources.

Peru has the second-highest diversity of birds in the world, but little is known about the interactions between birds and plastic waste. To fill this knowledge gap, we searched the scientific literature, collected information from social networks such as Facebook and databases such as Macaulay Library and iNaturalist and solicited records through messaging with researchers and bird enthusiasts. We found 119 bird interactions with plastic debris involving 39 species from 20 families, with the red-legged cormorant Phalacrocorax gaimardi and the neotropical cormorant Phalacrocorax brasilianus being the most affected species. By type of interaction category, plastic waste in nests was the most abundant, followed by entanglement, capture and handling and ingestion. Ropes, nets and soft plastics such as bags were the most frequently reported types of waste. As our methodology has limitations, it is probable that other species that also interact with plastic waste have not been reported, so we recommend further study.

The anthropogenic spread of disease from captive to wild amphibian populations (referred to as spillover) is linked to global amphibian declines. Disinfecting procedures and protocols exist to mitigate pathogen transmission to and within natural areas, but understanding of visitor attitudes and behaviour regarding their adoption is limited. We surveyed visitors in two natural areas in a global amphibian biodiversity hotspot to assess their attitudes regarding pathogen spread in such areas and analysed the factors influencing their behavioural intentions to take specific actions to prevent pathogen spillover. Visitors’ willingness to take action was influenced by their attitudes, behavioural control and trust in wildlife/land managers, whereas socio-demographic characteristics were less influential. These findings help us to understand visitor behaviour with respect to amphibian biosecurity in natural areas and inform enhanced biosecurity measures and strategic messaging to reduce pathogen spillover.