Roads are proliferating worldwide at an unprecedented rate, with potentially severe impacts on wildlife. We calculated the extent and potential impacts of road networks across the 1,160,000-km2, 13-country range of the globally endangered tiger (Panthera tigris)—a conservation umbrella species. We found that roads were pervasive, totaling 134,000 km across tiger conservation landscapes (TCLs), even in tiger priority sites and protected areas. Approximately 43% of the area where tiger breeding occurs and 57% of the area in TCLs fell within the road-effect zone. Consequently, current road networks may be decreasing tiger and prey abundances by more than 20%. Nearly 24,000 km of new roads will be built in TCLs by 2050, stimulated through major investment projects such as China’s Belt and Road Initiative. Given that roads will be a pervasive challenge to tiger recovery in the future, we urge decision-makers to make sustainable road development a top priority.

Human-induced rapid environmental change (HIREC) can have dramatic impacts on ecosystems, leading to rapid trait changes in some organisms and extinction in others. Such changes in traits signify that human actions can lead to cases of increased phenotypic diversity and consequently can strongly impact population-, community- and ecosystem-level dynamics. Here, we examine whether the ecological consequences of habitat fragmentation have led to changes in the life histories of three native species of mosquitofish (Gambusia spp.) inhabiting tidal creeks on six different Bahamian islands. We address two important questions: (i) How predictable and parallel are life-history changes in response to HIREC across islands and species, and (ii) what is the relative importance of shared (i.e. parallel) responses to fragmentation, differences between species or islands and species- or island-specific responses to fragmentation? Phenotypic differences between fragmentation regimes were as great or greater than differences between species or islands. While some adult life histories (lean weight and fat content) showed strong, shared responses to fragmentation, offspring-related life histories (embryo fat and fecundity) exhibited idiosyncratic, island-specific responses. While shared responses to fragmentation appeared largely driven by a reduction in piscivorous fish density, increased conspecific density and changes in salinity, we found some evidence that among-population variation in male reproductive investment and embryo fat content may have arisen via variation in conspecific density. Our results suggest that phenotypic responses to HIREC can be complex, with the predictability of response varying across traits. We therefore emphasize the need for more theoretical and empirical work to better understand the predictability of phenotypic responses to human-induced disturbances.

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Mesocarnivores constitute a diverse and often abundant group of species, which are increasingly occupying hweigher trophic levels within multi‐use landscapes. Yet, we know relatively little about their interactions with each other, especially in human‐altered areas. Using camera trap data collected in a forestry concession in the Greater Gorongosa ecosystem of central Mozambique, we examined the spatiotemporal relationships and potential for intraguild competition among three understudied African carnivores: African civets (Civettictis civetta), bushy‐tailed mongooses (Bdeogale crassicauda), and large‐spotted genets (Genetta maculata). After accounting for habitat preferences and tolerance to anthropogenic factors, we found that African civets and bushy‐tailed mongooses avoid each other spatially and temporally. Additionally, civets and mongooses were also both more likely to use sites farther away from human settlements, possibly decreasing the total available habitat for each species if competition is driving this spatial partitioning. In contrast, we did not find evidence for spatial or temporal partitioning between large‐spotted genets and African civets, but bushy‐tailed mongooses altered their activity patterns where they co‐occurred with genets. Our study contributes to scant ecological knowledge of these mesocarnivores and adds to our understanding of community dynamics in human‐altered ecosystems.

ABSTRACT. Information, energy, and materials are flowing over greater distances than in the past, changing the structure and feedbacks within and across coupled human and natural systems worldwide. The telecoupling framework was recently developed to understand the feedbacks and multidirectional flows characterizing social and environmental interactions between distant systems. We extend the application of the telecoupling framework to illustrate how flows in beef affect and are affected by social-ecological processes occurring between distant systems in Africa, and how those dynamics will likely change over the next few decades because of climate-induced shifts in a major bovine disease, trypanosomosis. The disease is currently wide-spread in Africa, affecting millions of cattle every year and resulting in massive economic losses. Increasing temperatures are predicted to substantially reduce the geographic range of the cattle disease by 2050 in regions of Africa, thereby potentially releasing cattle from disease control in those areas. Despite the societal and economic benefits, greater cattle production can also lead to significant environmental degradation. Our investigation takes a qualitative, yet systematic, approach to explore how changes in the regional distribution of cattle production, caused by shifts in the bovine disease, will affect the social and ecological conditions of the telecoupled system in the future. Doing so lays the groundwork to quantify telecouplings and improve decision making under uncertainty in the future.

Illicit supply networks (ISNs) are composed of coordinated human actors that source, transit, and distribute illicitly traded goods to consumers, while also creating widespread social and environmental harms. Despite growing documentation of ISNs and their impacts, efforts to understand and disrupt ISNs remain insufficient due to the persistent lack of knowledge connecting a given ISN's modus operandi and its patterns of activity in space and time. The core challenge is that the data and knowledge needed to integrate it remain fragmented and/or compartmentalized across disciplines, research groups, and agencies tasked with understanding or monitoring one or a few specific ISNs. One path forward is to conduct comparative analyses of multiple diverse ISNs. We present and apply a conceptual framework for linking ISN modus operandi to spatial-temporal dynamics and patterns of activity. We demonstrate this through a comparative analysis of three ISNs -cocaine, illegally traded wildlife, and illegally mined sand -which range from well-established to emergent, global to domestic in geographic scope, and fully illicit to de facto legal. The proposed framework revealed consistent traits related to geographic price structure, value capture at different supply chain stages, and key differences among ISN structure and operation related to commodity characteristics and their relative illicitness. Despite the diversity of commodities and ISN attributes compared, social and environmental harms inflicted by the illicit activity consistently become more widespread with increasing law enforcement disruption. Drawing on these lessons from diverse ISNs, which varied in their histories and current sophistication, possible changes in the structure and function of nascent and/or low salience ISNs may be anticipated if future conditions or law enforcement pressure change.

This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

1. Illegal wildlife trade is a global threat to biodiversity, but its drivers and impacts and ways to combat it vary by taxa. News media framing of instances of illegal trade provides a novel window into understanding public perceptions of these dynamics and potential support for management actions.2. We used 54 known cases of illegal turtle trade in the United States occurring between 1998 and 2021 as a case study to investigate news media framing of this emergent issue in illegal wildlife trade. We synthesized information from these cases and qualitatively analysed how they were framed in 217 associated news articles.3. The 54 cases involved the illegal trade of at least 24,000 freshwater turtles of 34 different species; box turtles (Terrapene spp.) were traded the most. Of the known species involved, 23 were listed under one of the CITES Appendices, and 12 were considered threatened by the International Union for the Conservation of Nature.Trade occurred in at least 43 US states and 6 countries.4. Despite the multifaceted nature of these cases, problem and solution framing were relatively unvarying. Media coverage framed foreign demand, particularly from Asia for high-value pet turtles, as a main driver of illegal trade. Solutions focused on regulations and enforcement which follows global trends in illegal wildlife trade discourses. However, we also found that articles neutralized illegal turtle trade in several ways, reflecting a lack of perceived legitimacy of and necessity for trade rules and enforcement. 5. Without acknowledging longstanding and formerly legal practices in wildlife trading, conservation efforts which focus on regulations and enforcement may be undermined by a lack of normative compliance.