Is there evidence of shifting baseline syndrome in environmental managers? An assessment using perceptions of bird population targets in UK nature reserves

Shifting baseline syndrome (SBS) describes changing perceptions of biological conditions due to a loss of historical knowledge. Perceptions of ‘normal’ environmental conditions are continually updated, leading to underestimation of the true magnitude of long-term ecological change and potential setting of unambitious management targets. There has been speculation as to the presence and impacts of SBS within conservation management since Daniel Pauly's seminal paper in 1995, which outlined the potential effects of SBS on target-setting in fisheries management. Previous case studies have suggested that SBS may not occur in management, despite empirical evidence of SBS in other systems. In this study, 44 professionals and volunteers involved in bird species management, monitoring and target-setting across England were interviewed. Interviews asked for personal perceptions of current, maximum and target abundance, long-term trends, and perceived conservation priority for six bird species. Using paired tests, this study found no significant effect of experience on perceptions of current, maximum or target abundance of all species, despite differences in national abundance and trends, and differences in participant experience. Further power analysis indicated that even if SBS was statistically detectible with a larger sample, the practical implications of the syndrome would be minimal due to small effect sizes. Finally, the effect of experience on individual perceptions of species conservation priority varied between species, with generational amnesia in the form of ‘lifting baselines’ suggested for only one of the six species. This study suggests that shifting baseline syndrome may not be as significant a threat in conservation management as first thought

Exploitation histories of pangolins and endemic pheasants on Hainan Island, China: baselines and shifting social norms

Overexploitation is a critical threat to the survival of many species. The global demand for wildlife products has attracted considerable research attention, but regional species exploitation histories are more rarely investigated. We interviewed 169 villagers living around seven terrestrial nature reserves on Hainan Island, China, with the aim of reconstructing historical patterns of hunting and consumption of local wildlife, including the globally threatened Chinese pangolin (Manis pentadactyla) and Hainan peacock-pheasant (Polyplectron katsumatae), from the mid-20th century onwards. We aimed to better understand the relationship between these past activities and current consumption patterns. Our findings suggest that eating pangolin meat was not a traditional behaviour in Hainan, with past consumption prohibited by local myths about pangolins. In contrast, local consumption of peacock-pheasant meat was a traditional activity. However, later attitudes around hunting pangolins and peacock-pheasants in Hainan were influenced by pro-hunting policies and a state-run wildlife trade from the 1960s to the 1980s. These new social norms still shape the daily lifestyles and perceptions of local people towards wildlife consumption in Hainan today. Due to these specific historical patterns of wildlife consumption, local-adapted interventions such as promoting substitute meat choices and alternative livelihoods might be effective at tackling local habits of consuming wild meat. Our study highlights the importance of understanding the local historical contexts of wildlife use for designing appropriate conservation strategies

Knowledge and attitudes about the use of pangolin scale products in Traditional Chinese Medicine (TCM) within China

1. All eight pangolin species are threatened with extinction, largely through demand for their products including scales, meat and body parts. The demand for pangolin scales has gained attention from many conservation groups due to the large volumes involved in illegal trade. Market demand in China is one of the major drivers for international illegal trade according to confiscation reports, and many conservation interventions have been attempted to reduce this demand. 2. The Traditional Chinese Medicine (TCM) community plays a key role in regulating legal trade and combating illegal trade in pangolin scales. However, this community has been largely overlooked by previous conservation interventions directed at the pangolin scale trade. There has also been little research into the involvement of the TCM community in pangolin scale trade in China. 3. To fill these knowledge gaps, we interviewed TCM doctors from 41 hospitals, shop owners/assistants from 90 TCM shops, two TCM wholesalers, and 2,168 members of the general public in Henan and Hainan provinces, China. Respondents' knowledge of and attitudes towards the pangolin scale trade were investigated using semi-structured and structured questionnaires, with a total of 2,301 respondents. 4. Our results show that TCM practitioners generally have poor awareness of the illegal nature of their behaviours and pangolin scale products involved. Awareness is particularly poor among participants at the end of the trade chain (i.e. end sellers). The public also generally lacked understanding of pangolin products in markets. 5. Results also show that 20 (71%) of 28 doctors believed that the use of pangolin scales in at least some, if not all, treatments could be substituted by other ingredients. 6. These findings suggest that raising awareness of the legality of pangolin scale products and petitioning TCM communities to use alternative substitutes for these products could constitute feasible and effective pangolin conservation interventions. 7. This study provides the first insights into the knowledge of and attitudes towards the pangolin scale trade from the perspective of TCM practitioners, and suggests that collaborating with the TCM community is necessary to combat this illegal trade

Simultaneous extinction of Madagascar’s megaherbivores correlates with late Holocene human-caused landscape transformation

Reconstructing the dynamics and drivers of late Quaternary megafaunal extinctions requires direct radiometric date series that are assessed within probabilistic statistical frameworks. Extinction chronologies are poorly understood for many tropical regions, including Madagascar, which had a diverse, now-extinct Holocene large vertebrate fauna including a “megaherbivore” guild of endemic hippopotami and elephant birds. Madagascar's megaherbivores likely played vital roles in regulating ecosystem structure and nutrient cycling, but few direct dates are available for megaherbivore specimens identified to species level, with uncertainty over when and why different representatives of this guild disappeared. Here, we conduct a new investigation into Malagasy megaherbivore extinction dynamics, including 30 new AMS dates and 63 audited published dates. We use Gaussian-resampled inverse-weighted McInerny (GRIWM) analysis to estimate species-specific extinction dates for three elephant bird species (Aepyornis hildebrandti, Mullerornis modestus, Vorombe titan), eggshell representing Aepyornis or Vorombe, and two hippo species (Hippopotamus lemerlei, H. madagascariensis), and to estimate extinction dates for megaherbivore communities in different biomes. Megaherbivores persisted for millennia after first human arrival. Extinction date estimates vary significantly between biomes, with disappearance from dry deciduous forest over a millennium earlier than other biomes, possibly reflecting local variation in megaherbivore population densities or human pressures. However, megaherbivore communities including all elephant bird and hippo species persisted elsewhere across Madagascar until ∼1200-900 bp, when they collapsed suddenly. Extinctions are closely correlated in time with intensive conversion of forests to grassland at ∼1100-1000 bp, probably associated with a shift to agro-pastoralism and representing a radical change in sustainability of prehistoric human interactions with biodiversity

Assessing the effectiveness of public awareness-raising initiatives for the Hainan gibbon Nomascus hainanus

Many protected areas conduct awareness-raising activities to increase local knowledge and support conservation programmes, but the effectiveness of such activities is rarely assessed. Public awareness-raising has been carried out since the early 2000s around Bawangling National Nature Reserve, Hainan, China, to improve conservation knowledge about the Critically Endangered Hainan gibbon Nomascus hainanus, one of the rarest mammals. We conducted 207 interviews in 25 villages around Bawangling National Nature Reserve to evaluate the outcome of previous conservation education, through comparison of variation in local respondent knowledge and attitudes, and specific enquiries about sources of knowledge acquisition. Likelihood of accurate responses to most of our questions regarding the species was positively correlated with local exposure to gibbon-themed billboards and murals, and respondents exhibited greater knowledge about several key conservation indices for gibbons compared to their knowledge about sympatrically occurring rhesus macaques Macaca mulatta. Many respondents specifically reported they knew about local existence, population size, conservation status, and threats to gibbons from past awareness-raising activities, with village education sessions and billboards widely identified as key sources of information. However, other known awareness-raising approaches have had little detectable effect on shaping local conservation awareness. Although educational activities have improved awareness about gibbons and their conservation requirements in relative terms, overall levels of knowledge remain low in many important areas and ongoing improvement of local awareness is still needed, in particular around poorly-understood topics such as gibbon conservation status, rarity and threats, and for socio-demographic groups possessing less conservation knowledge

Biodiversity conservation and the earth system – mind the gap

One of the most striking human impacts on global biodiversity is the ongoing depletion of large vertebrates from terrestrial and aquatic ecosystems. Recent work suggests this loss of megafauna can affect processes at biome or Earth system scales with potentially serious impacts on ecosystem structure and function, ecosystem services, and biogeochemical cycles. We argue that our contemporary approach to biodiversity conservation focuses on spatial scales that are too small to adequately address these impacts. We advocate a new global approach to address this conservation gap, which must enable megafaunal populations to recover to functionally relevant densities. We conclude that re-establishing biome and Earth system functions needs to become an urgent global priority for conservation science and policy

Effects of protected areas on survival of threatened gibbons in China

Establishing protected areas (PAs) is an essential strategy to reduce biodiversity loss. However, many PAs do not provide adequate protection due to poor funding, inadequate staffing and equipment, and ineffective management. As part of China's recent economic growth, the Chinese government has significantly increased investment in nature reserves over the past 20 years, providing a unique opportunity to evaluate whether PAs can protect threatened species effectively. We compiled data from published literature on populations of gibbons (Hylobatidae), a threatened taxon with cultural significance, that occurred in Chinese reserves after 1980. We evaluated the ability of these PAs to maintain gibbon habitat and populations by comparing forest cover and human disturbance between reserves and their surrounding areas and modeling the impact of reserve characteristics on gibbon population trends. We also assessed the perspective of reserve staff concerning PA management effectiveness through an online survey. Reserves effectively protected gibbon habitat by reducing forest loss and human disturbance; however, half the reserves lost their gibbon populations since being established. Gibbons were more likely to survive in reserves established more recently, at higher elevation, with less forest loss and lower human impact, and that have been relatively well studied. A larger initial population size in the 1980s was positively associated with gibbon persistence. Although staff of all reserves reported increased investment and improved management over the past 20–30 years, no relationship was found between management effectiveness and gibbon population trends. We suggest early and emphatic intervention is critical to stop population decline and prevent extinction

Where the wild things were: intrinsic and extrinsic extinction predictors in the world’s most depleted mammal fauna

Preventing extinctions requires understanding macroecological patterns of vulnerability or persistence. However, correlates of risk can be nonlinear, within-species risk varies geographically, and current-day threats cannot reveal drivers of past losses. We investigated factors that regulated survival or extinction in Caribbean mammals, which have experienced the globally highest level of human-caused postglacial mammalian extinctions, and included all extinct and extant Holocene island populations of non-volant species (219 survivals or extinctions across 118 islands). Extinction selectivity shows a statistically detectable and complex body mass effect, with survival probability decreasing for both mass extremes, indicating that intermediatesized species have been more resilient. A strong interaction between mass and age of first human arrival provides quantitative evidence of larger mammals going extinct on the earliest islands colonized, revealing an extinction filter caused by past human activities. Survival probability increases on islands with lower mean elevation (mostly small cays acting as offshore refugia) and decreases with more frequent hurricanes, highlighting the risk of extreme weather events and rising sea levels to surviving species on low-lying cays. These findings demonstrate the interplay between intrinsic biology, regional ecology and specific local threats, providing insights for understanding drivers of biodiversity loss across island systems and fragmented habitats worldwide

The past and future human impact on mammalian diversity

To understand the current biodiversity crisis, it is crucial to determine how humans have affected biodiversity in the past. However, the extent of human involvement in species extinctions from the Late Pleistocene onward remains contentious. Here, we apply Bayesian models to the fossil record to estimate how mammalian extinction rates have changed over the past 126,000 years, inferring specific times of rate increases. We specifically test the hypothesis of human-caused extinctions by using posterior predictive methods. We find that human population size is able to predict past extinctions with 96% accuracy. Predictors based on past climate, in contrast, perform no better than expected by chance, suggesting that climate had a negligible impact on global mammal extinctions. Based on current trends, we predict for the near future a rate escalation of unprecedented magnitude. Our results provide a comprehensive assessment of the human impact on past and predicted future extinctions of mammals