A role for selective contraception of individuals in conservation

Contraception has an established role in managing overabundant populations and preventing undesirable breeding in zoos. We propose that it can also be used strategically and selectively in conservation to increase the genetic and behavioral quality of the animals. In captive breeding programs, it is becoming increasingly important to maximize the retention of genetic diversity by managing the reproductive contribution of each individual and preventing genetically suboptimal breeding through the use of selective contraception. Reproductive suppression of selected individuals in conservation programs has further benefits of allowing animals to be housed as a group in extensive enclosures without interfering with breeding recommendations, which reduces adaptation to captivity and facilitates the expression of wild behaviors and social structures. Before selective contraception can be incorporated into a breeding program, the most suitable method of fertility control must be selected, and this can be influenced by factors such as species life history, age, ease of treatment, potential for reversibility, and desired management outcome for the individual or population. Contraception should then be implemented in the population following a step‐by‐step process. In this way, it can provide crucial, flexible control over breeding to promote the physical and genetic health and sustainability of a conservation dependent species held in captivity. For Tasmanian devils (Sarcophilus harrisii), black‐flanked rock wallabies (Petrogale lateralis), and burrowing bettongs (Bettongia lesueur), contraception can benefit their conservation by maximizing genetic diversity and behavioral integrity in the captive breeding program, or, in the case of the wallabies and bettongs, by reducing populations to a sustainable size when they become locally overabundant. In these examples, contraceptive duration relative to reproductive life, reversibility, and predictability of the contraceptive agent being used are important to ensure the potential for individuals to reproduce following cessation of contraception, as exemplified by the wallabies when their population crashed and needed females to resume breeding.     

Land‐use trade‐offs between tree biodiversity and crop production in the Atlantic Forest

Trade‐offs in ecosystem services (ES) have received increasing attention because provisioning services often come at the expense of biodiversity loss. When land‐use patterns are not maximally efficient relative to productivity, provisioning services, such as crop production, can often be increased without losing biodiversity. The Atlantic Forest (AF) encompasses dense, mixed, and seasonal forests and has high levels of endemism and anthropogenic threat. We examined trade‐offs between biodiversity and crop production in the AF to provide insights into land‐use management decisions. We developed a biodiversity metric that combines information on tree species richness, evolutionary distinctiveness, and rarity at the local level. We examined the extent to which the nature of ES trade‐offs differ among the 3 forest types. We assessed how annual deforestation rates and land management practices affect biodiversity and agricultural revenues. Finally, we tested whether it is possible to achieve the same total regional revenue without reducing biodiversity by improving local management practices. The 3 forest types had similar patterns in ES trade‐offs, although within mixed forest patterns differed. Biodiversity appeared to be more sensitive to land‐use change than crop revenues. Certain crops yielded up to 10 times higher values in some sites. Enhanced crop productivity may increase revenues without reducing biodiversity. Our results showed that to enhance human well‐being without further conversion of AF, maximizing crop productivity is needed . Increasing efficiency of management outcomes by maintaining higher biodiversity and increasing provisioning services depends on knowledge of forest type, the comparative advantage of planting crops in the best places, and preserving species in a balanced manner across forests.     

Using interview surveys and multispecies occupancy models to inform vertebrate conservation

Species distribution data are an essential biodiversity variable requiring robust monitoring to inform wildlife conservation. Yet, such data remain inherently sparse because of the logistical challenges of monitoring biodiversity across broad geographic extents. Surveys of people knowledgeable about the occurrence of wildlife provide an opportunity to evaluate species distributions and the ecology of wildlife communities across large spatial scales. We analyzed detection histories of 30 vertebrate species across the Western Ghats biodiversity hotspot in India, obtained from a large-scale interview survey of 2318 people who live and work in the forests of this region. We developed a multispecies occupancy model that simultaneously corrected for false-negative (non-detection) and false-positive (misidentification) errors that interview surveys can be prone to. Using this model, we integrated data across species in composite analyses of the responses of functional species groups (based on disturbance tolerance, diet, and body mass traits) to spatial variation in environmental variables, protection, and anthropogenic pressures. We observed a positive association between forest cover and the occurrence of species with low tolerance of human disturbance. Protected areas were associated with higher occurrence for species across different functional groups compared with unprotected lands. We also observed the occurrence of species with low disturbance tolerance, herbivores, and large-bodied species was negatively associated with developmental pressures, such as human settlements, energy production and mining, and demographic pressures, such as biological resource extraction. For the conservation of threatened vertebrates, our work underscores the importance of maintaining forest cover and reducing deforestation within and outside protected areas, respectively. In addition, mitigating a suite of pervasive human pressures is also crucial for wildlife conservation in one of the world's most densely populated biodiversity hotspots.     

The perpetual state of emergency that sacrifices protected areas in a changing climate

A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus.     

A moral panic over cats

Some conservationists believe that free-ranging cats pose an enormous risk to biodiversity and public health and therefore should be eliminated from the landscape by any means necessary. They further claim that those who question the science or ethics behind their arguments are science deniers (merchants of doubt) seeking to mislead the public. As much as we share a commitment to conservation of biodiversity and wild nature, we believe these ideas are wrong and fuel an unwarranted moral panic over cats. Those who question the ecological or epidemiological status of cats are not science deniers, and it is a false analogy to compare them with corporate and right-wing special interests that perpetrate disinformation campaigns over issues, such as smoking and climate change. There are good conservation and public-health reasons and evidence to be skeptical that free-ranging cats constitute a disaster for biodiversity and human health in all circumstances. Further, there are significant and largely unaddressed ethical and policy issues (e.g., the ethics and efficacy of lethal management) relative to how people ought to value and coexist with cats and native wildlife. Society is better served by a collaborative approach to produce better scientific and ethical knowledge about free-ranging cats.     

Estimating non-native plant richness with a species-accumulation model along roads

Monitoring non-native plant richness is important for biodiversity conservation and scientific research. The species-area model (SA model) has been used frequently to estimate the total species richness within a region. However, the conventional SA model may not provide robust estimations of non-native plant richness because the ecological processes associated with the accumulation of exotic and native plants may differ. Because roads strongly dictate the distributions of exotic plants, we propose a species-accumulation model along roads (SR model), rather than an SA model, to estimate the non-native plant richness within a region. Using 270 simulated data sets, we compared the differences in performance between the SR and SA models. A decision tree based on prediction accuracy was created to guide model application, which was validated using field data from 3 national nature reserves in 3 different provinces in China. The SR model significantly outperformed the SA model when non-native species were restricted to the roadsides and the proportion of uncommon exotic species was small. More importantly, the SR model accurately estimated the non-native plant richness in all field sites with an error of <1 species per site. We believe our new model meets the practical need to efficiently and robustly estimate non-native plant richness, which may facilitate effective biodiversity conservations and promote research on non-native plant invasion and vegetation dynamics.     

Linking life history to landscape for threatened species conservation in a multiuse region

Landscape-scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial–environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision-making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial–environmental associations and linking them to life-history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision-making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally.     

Effect of semantics in the study of tolerance for wolves

As conservation scholars increasingly recognize the critical role of human thought and behavior in determining the persistence of biodiversity across the globe, a growing line of inquiry regarding the validity and comparability of previous applications of core psychological concepts has emerged. Specifically, inconsistent measurement and use of terms, such as attitudes and acceptance, reveal important questions about previous approaches. Given that these concepts differ by definition, yet have been used interchangeably, we explored what drives differences in people's responses when each concept is operationalized in the context of a contested wildlife species, the gray wolf (Canis lupus). To do so, we used data from a 2014 survey of U.S. residents (n = 1287) to test how measures of six concepts (i.e., acceptance, attitudes, benefits, risks, [prior] behavior, and behavioral intentions) often employed in the conservation social sciences were related with a broad set of possible explanatory variables. Despite moderate to strong correlations between all concepts measured (| Pearson's r | = 0.39–0.65, p < 0.001), results revealed considerable variation in their respective relationships with identical explanatory variables. Specifically, although wildlife value orientation (i.e., domination or mutualism) operated fairly consistently across cognitive and behavioral concepts, the relationship between the six concepts and other factors, such as social trust, identification with various interest groups (i.e., hunter, farmer, or rancher, environmentalist, and animal rights advocate), and political ideology (i.e., liberal vs. conservative), varied considerably. Our findings underscore that differences exist in these measures, which could have serious implications for conservationists integrating social science findings in their decision-making processes if they are unaware of the theoretical underpinnings of and distinctions between core psychological concepts.     

Savviness of prey to introduced predators

The prey naivety hypothesis posits that prey are vulnerable to introduced predators because many generations in slow gradual coevolution are needed for appropriate avoidance responses to develop. It predicts that prey will be more responsive to native than introduced predators and less responsive to introduced predators that differ substantially from native predators and from those newly established. To test these predictions, we conducted a global meta-analysis of studies that measured the wariness responses of small mammals to the scent of sympatric mammalian mesopredators. We identified 26 studies that met our selection criteria. These studies comprised 134 experiments reporting on the responses of 36 small mammal species to the scent of six introduced mesopredators and 12 native mesopredators. For each introduced mesopredator, we measured their phylogenetic and functional distance to local native mesopredators and the number of years sympatric with their prey. We used predator and prey body mass as a measure of predation risk. Globally, small mammals were similarly wary of the scent of native and introduced mesopredators; phylogenetic and functional distance between introduced mesopredators and closest native mesopredators had no effect on wariness; and wariness was unrelated to the number of prey generations, or years, since first contact with introduced mesopredators. Small mammal wariness was associated with predator-prey body mass ratio, regardless of the nativity. The one thing animals do not seem to recognize is whether their predators are native.     

Sentiment analysis of the Twitter response to Netflix's Our Planet documentary

The role of nature documentaries in shaping public attitudes and behavior toward conservation and wildlife issues is unclear. We analyzed the emotional content of over 2 million tweets related to Our Planet, a major nature documentary released on Netflix, with dictionary and rule-based automatic sentiment analysis. We also compared the sentiment associated with species mentioned in Our Planet and a set of control species with similar features but not mentioned in the documentary. Tweets were largely negative in sentiment at the time of release of the series. This effect was primarily linked to the highly skewed distributions of retweets and, in particular, to a single negatively valenced and massively retweeted tweet (>150,000 retweets). Species mentioned in Our Planet were associated with more negative sentiment than the control species, and this effect coincided with a short period following the airing of the series. Our results are consistent with a general negativity bias in cultural transmission and document the difficulty of evoking positive sentiment, on social media and elsewhere, in response to environmental problems.