As threats to species continue to increase, precise and unbiased measures of the impact these pressures are having on global biodiversity are urgently needed. Some existing indicators of the status ...and trends of biodiversity largely rely on publicly available data from the scientific and grey literature, and are therefore prone to biases introduced through over-representation of well-studied groups and regions in monitoring schemes. This can give misleading estimates of biodiversity trends. Here, we report on an approach to tackle taxonomic and geographic bias in one such indicator (Living Planet Index) by accounting for the estimated number of species within biogeographical realms, and the relative diversity of species within them. Based on a proportionally weighted index, we estimate a global population decline in vertebrate species between 1970 and 2012 of 58% rather than 20% from an index with no proportional weighting. From this data set, comprising 14,152 populations of 3,706 species from 3,095 data sources, we also find that freshwater populations have declined by 81%, marine populations by 36%, and terrestrial populations by 38% when using proportional weighting (compared to trends of -46%, +12% and +15% respectively). These results not only show starker declines than previously estimated, but suggests that those species for which there is poorer data coverage may be declining more rapidly.
New technologies have vastly increased the available data on animal movement and behaviour. Consequently, new methods deciphering the spatial and temporal interactions between individuals and their ...environments are vital. Network analyses offer a powerful suite of tools to disentangle the complexity within these dynamic systems, and we review these tools, their application, and how they have generated new ecological and behavioural insights. We suggest that network theory can be used to model and predict the influence of ecological and environmental parameters on animal movement, focusing on spatial and social connectivity, with fundamental implications for conservation. Refining how we construct and randomise spatial networks at different temporal scales will help to establish network theory as a prominent, hypothesis-generating tool in movement ecology.
Network theory is developing in its application across multiple disciplines.
Animal movement networks can reveal important insight about ecological connectivity.
Further development is necessary to fully encapsulate temporal dynamics.
We discuss using network metrics to understand spatial and social ecology.
Pollinating species are in decline globally, with land use an important driver. However, most of the evidence on which these claims are made is patchy, based on studies with low taxonomic and ...geographic representativeness. Here, we model the effect of land-use type and intensity on global pollinator biodiversity, using a local-scale database covering 303 studies, 12,170 sites, and 4502 pollinating species. Relative to a primary vegetation baseline, we show that low levels of intensity can have beneficial effects on pollinator biodiversity. Within most anthropogenic land-use types however, increasing intensity is associated with significant reductions, particularly in urban (43% richness and 62% abundance reduction compared to the least intensive urban sites), and pasture (75% abundance reduction) areas. We further show that on cropland, the strongly negative response to intensity is restricted to tropical areas, and that the direction and magnitude of response differs among taxonomic groups. Our findings confirm widespread effects of land-use intensity on pollinators, most significantly in the tropics, where land use is predicted to change rapidly.
Ecological systematic reviews and meta‐analyses have significantly increased our understanding of global biodiversity decline. However, for some ecological groups, incomplete and biased datasets have ...hindered our ability to construct robust, predictive models. One such group consists of the animal pollinators. Approximately 88% of wild plant species are thought to be pollinated by animals, with an estimated annual value of $230–410 billion dollars. Here we apply text‐analysis to quantify the taxonomic and geographical distribution of the animal pollinator literature, both temporally and spatially. We show that the publication of pollinator literature increased rapidly in the 1980s and 1990s. Taxonomically, we show that the distribution of pollinator literature is concentrated in the honey bees (Apis) and bumble bees (Bombus), and geographically in North America and Europe. At least 25% of pollination‐related s mention a species of honey bee and at least 20% a species of bumble bee, and approximately 46% of s are focussed on either North America (32%) or Europe (14%). Although these results indicate strong taxonomic and geographic biases in the pollinator literature, a large number of studies outside North America and Europe do exist. We then discuss how text‐analysis could be used to shorten the literature search for ecological systematic reviews and meta‐analyses, and to address more applied questions related to pollinator biodiversity, such as the identification of likely interacting plant–pollinator pairs and the number of pollinating species.
Passive acoustic sensing has emerged as a powerful tool for quantifying anthropogenic impacts on biodiversity, especially for echolocating bat species. To better assess bat population trends there is ...a critical need for accurate, reliable, and open source tools that allow the detection and classification of bat calls in large collections of audio recordings. The majority of existing tools are commercial or have focused on the species classification task, neglecting the important problem of first localizing echolocation calls in audio which is particularly problematic in noisy recordings. We developed a convolutional neural network based open-source pipeline for detecting ultrasonic, full-spectrum, search-phase calls produced by echolocating bats. Our deep learning algorithms were trained on full-spectrum ultrasonic audio collected along road-transects across Europe and labelled by citizen scientists from www.batdetective.org. When compared to other existing algorithms and commercial systems, we show significantly higher detection performance of search-phase echolocation calls with our test sets. As an example application, we ran our detection pipeline on bat monitoring data collected over five years from Jersey (UK), and compared results to a widely-used commercial system. Our detection pipeline can be used for the automatic detection and monitoring of bat populations, and further facilitates their use as indicator species on a large scale. Our proposed pipeline makes only a small number of bat specific design decisions, and with appropriate training data it could be applied to detecting other species in audio. A crucial novelty of our work is showing that with careful, non-trivial, design and implementation considerations, state-of-the-art deep learning methods can be used for accurate and efficient monitoring in audio.
Negotiating joint routes during group travel is one of the challenges faced by collectively moving animals, on spatial scales ranging from daily foraging trips to long-distance migrations. Homing ...pigeons, Columba livia, provide a useful model system for studying the mechanisms of group decision making in the context of navigation, owing to the combination of their gregarious nature and the depth of our understanding of their individual orientational strategies. Previous work has shown that during paired flight, if two birds’ individually preferred routes are sufficiently different, one bird will emerge as leader whom the other follows. What determines the identity of a leader has important implications for the efficiency of a moving collective, since leaders with higher navigational certainty can increase the accuracy of the group. We examined factors contributing to the establishment of leadership/followership, focusing on the role of previous navigational experience. We tested, on a homing task, pairs of pigeons in which the two partners had relatively greater and lesser prior experience, generated through individual training. Analysis of the GPS-tracked routes taken by such pairs revealed a negative correlation between homing experience and the probability that a pigeon would follow a co-navigating partner. Thus, the larger the difference in experience between two partners, the higher the likelihood the more experienced bird would emerge as leader. Our results contribute to a better understanding of the mechanisms and potential payoffs of collective navigational decision making in species that travel in mixed-experience groups.
► Study explores mechanisms of collective decision making in pigeon group navigation. ► Navigational experience is hypothesized to affect leadership in heterogeneous groups. ► Results show that more experienced birds are more likely to emerge as leaders. ► This tendency is more pronounced when difference between birds’ experience is large. ► Spontaneous leadership by experienced individuals can increase efficiency of group.
Navigational control of avian migration is understood, largely from the study of terrestrial birds, to depend on either genetically or culturally inherited information. By tracking the individual ...migrations of Atlantic Puffins, Fratercula arctica, in successive years using geolocators, we describe migratory behaviour in a pelagic seabird that is apparently incompatible with this view. Puffins do not migrate to a single overwintering area, but follow a dispersive pattern of movements changing through the non-breeding period, showing great variability in travel distances and directions. Despite this within-population variability, individuals show remarkable consistency in their own migratory routes among years. This combination of complex population dispersion and individual route fidelity cannot easily be accounted for in terms of genetic inheritance of compass instructions, or cultural inheritance of traditional routes. We suggest that a mechanism of individual exploration and acquired navigational memory may provide the dominant control over Puffin migration, and potentially some other pelagic seabirds, despite the apparently featureless nature of the ocean.
Although threats to global biodiversity are well known, slowing current rates of biodiversity loss remains a challenge. The Aichi targets set out 20 goals on which the international community should ...act to alleviate biodiversity decline, 1 of which (Target 1) aims to raise public awareness of the importance of biodiversity. Although conventional indicators for Target 1 are of low spatial and temporal coverage, conservation culturomics metrics show how biodiversity awareness can be quantified at the global scale. Following methods used for the Living Planet Index, we devised a species awareness index (SAI) to measure change in species awareness based on Wikipedia views. We calculated this index at the page level for 41,197 species listed by the International Union for Conservation of Nature (IUCN) across 10 Wikipedia languages and >2 billion views from 1 July 2015 to 30 March 2020. Bootstrapped indices for the page‐level SAI showed that overall awareness of biodiversity increased marginally over time, although there were differences among taxonomic classes and languages. Among taxonomic classes, overall awareness increased fastest for reptiles and slowest for amphibians. Among languages, overall species awareness increased fastest for Japanese and slowest for Chinese and German users. Although awareness of species as a whole increased and was significantly higher for traded species, from January 2016 through January 2020, change in awareness appeared not to be strongly related to whether the species is traded or is a pollinator. As a data source for public biodiversity awareness, the SAI could be integrated into the Conservation International Biodiversity Engagement Indicator.
El Índice de Sensibilización de Especie como Medida de Culturomia de la Conservación para la Sensibilización Pública por la Biodiversidad
Resumen
Aunque las amenazas a la biodiversidad mundial son bien conocidas, reducir las tasas actuales de pérdida de la biodiversidad todavía es un desafío. Los objetivos de Aichi establecieron 20 metas para las cuales debe actuar la comunidad internacional para aliviar la declinación de la biodiversidad. Una de estas metas (Objetivo 1) busca sensibilizar al público sobre la importancia de la biodiversidad. Aunque los indicadores convencionales del Objetivo 1 tienen una baja cobertura espacial y temporal, las medidas de culturomia para la conservación muestran cómo la sensibilización por la biodiversidad puede cuantificarse a escala global. Seguimos los métodos utilizados para el Índice del Planeta Viviente para diseñar un índice de sensibilización de especie (ISE) para medir el cambio en la sensibilización por una especie con base en las vistas en Wikipedia. Calculamos este índice a nivel de página para 41,197 especies incluidas en las listas de la Unión Internacional para la Conservación de la Naturaleza (UICN) en diez diferentes idiomas en Wikipedia y más de 2 mil millones de vistas entre el 1 de julio de 2015 y el 30 de marzo de 2020. Los índices de arranque para el ISE a nivel de página mostraron que la sensibilización general por la biodiversidad incrementó ligeramente con el tiempo, aunque hubo diferencia entre las clasificaciones taxonómicas y los idiomas. Entre las clasificaciones taxonómicas, la sensibilización general incrementó más rápido para los reptiles y más lento para los anfibios. Entre los idiomas, la sensibilización general por especie incrementó más rápido para los usuarios del japonés y más lento para los usuarios del chino y el alemán. Aunque la sensibilización por las especies en su totalidad incrementó y fue significativamente más alta para las especies comercializadas, entre enero de 2016 y enero de 2020 el cambio en la sensibilización pareció no estar relacionado fuertemente con si la especie es un polinizador o es comercializada. Como fuente de información para la sensibilización pública por la biodiversidad, el ISE podría ser integrado dentro del Indicador de Participación Internacional para la Conservación de la Biodiversidad.
摘要
尽管全球生物多样性面临的威胁已众所周知, 但要减缓目前生物多样性丧失的速度仍然是一项挑战。 “爱知目标” 提出了 20 个目标来要求国际社会采取行动以缓解生物多样性下降, 其中一个目标 (目标 1) 旨在提高公众对生物多样性重要性的认识。虽然目标 1 的传统指标的时空覆盖度较低, 但保护文化组学指标展示了如何在全球范围内量化生物多样性意识。我们效仿地球生命力指数 (Living Planet Index) 的方法设计了一个物种认知指数, 基于维基百科的浏览量来衡量人们对物种认识的变化。针对国际自然保护联盟 (IUCN) 列出的 41,197 个物种, 我们在 10 种语言的维基百科上基于 2015 年 7 月 1 日到 2020 年 3 月 30 日间超过 20 亿次页面浏览量计算了这个指数。基于网页的物种认知的引导指数显示, 尽管在类群和语言之间存在差异, 但人们对生物多样性的总体意识随时间推移都稍有提高。在不同类群中, 人们对爬行动物的整体认识增长最快, 而两栖动物的增长最慢。在不同语言中, 日语使用者的总体物种认知增长最快, 而中文和德语使用者的则增长最慢。尽管人们对物种的认识整体上有所提高, 且对贸易物种的认识明显更多, 但从 2016 年 1 月到 2020 年 1 月物种认知的变化似乎与该物种是否受贸易或是否为传粉者无关。物种认知指数作为公众生物多样性意识的数据来源, 可以纳入国际生物多样性保护参与指标之中。【翻译 :胡怡思 ;审校 :聂永刚】
Article impact statement: Wikipedia represents a powerful data source for developing indicators of public biodiversity awareness.
Large, remote marine protected areas (MPAs) containing both reef and pelagic habitats, have been shown to offer considerable refuge to populations of reef‐associated sharks. Many large MPAs are, ...however, impacted by illegal fishing activity conducted by unlicensed vessels. While enforcement of these reserves is often expensive, it would likely benefit from the integration of ecological data on the mobile animals they are designed to protect. Consequently, shark populations in some protected areas continue to decline, as they remain a prime target for illegal fishers.
To understand shark movements and their vulnerability to illegal fishing, 3 years of acoustic tracking data, from 101 reef‐associated sharks, were analysed as movement networks to explore the predictability of movement patterns and identify key movement corridors within the British Indian Ocean Territory (BIOT) MPA. We examined how space use and connectivity overlap with spatially explicit risk of illegal fishing, through data obtained from the management consultancy enforcing the MPA.
Using individual‐based models, the movement networks of two sympatric shark species were efficiently predicted with distance‐decay functions (>95% movements accurately predicted). Model outliers were used to highlight the locations with unexpectedly high movement rates where MPA enforcement patrols might most efficiently mitigate predator removal.
Activity space estimates and network metrics illustrate that silvertip sharks were more dynamic, less resident and link larger components of the MPA than grey reef sharks. However, we show that this behaviour potentially enhances their exposure to illegal fishing activity.
Synthesis and applications. Marine protected area (MPA) enforcement strategies are often limited by resources. The British Indian Ocean Territory MPA, one of the world's largest ‘no take’ MPAs, has a single patrol vessel to enforce 640,000 km2 of open ocean, atoll and reef ecosystems. We argue that to optimize the patrol vessel search strategy and thus enhance their protective capacity, ecological data on the space use and movements of desirable species, such as large‐bodied reef predators, must be incorporated into management plans. Here, we use electronic tracking data to evaluate how shark movement dynamics influence species mortality trajectories in exploited reef ecosystems. In doing so we discuss how network analyses of such data might be applied for protected area enforcement.
Marine protected area (MPA) enforcement strategies are often limited by resources. The British Indian Ocean Territory MPA, one of the world's largest ‘no take’ MPAs, has a single patrol vessel to enforce 640,000 km2 of open ocean, atoll and reef ecosystems. We argue that to optimize the patrol vessel search strategy and thus enhance their protective capacity, ecological data on the space use and movements of desirable species, such as large‐bodied reef predators, must be incorporated into management plans. Here, we use electronic tracking data to evaluate how shark movement dynamics influence species mortality trajectories in exploited reef ecosystems. In doing so we discuss how network analyses of such data might be applied for protected area enforcement.
Analyses of animal social networks have frequently benefited from techniques derived from other disciplines. Recently, machine learning algorithms have been adopted to infer social associations from ...time-series data gathered using remote, telemetry systems situated at provisioning sites. We adapt and modify existing inference methods to reveal the underlying social structure of wide-ranging marine predators moving through spatial arrays of passive acoustic receivers. From six months of tracking data for grey reef sharks (Carcharhinus amblyrhynchos) at Palmyra atoll in the Pacific Ocean, we demonstrate that some individuals emerge as leaders within the population and that this behavioural coordination is predicted by both sex and the duration of co-occurrences between conspecifics. In doing so, we provide the first evidence of long-term, spatially extensive social processes in wild sharks. To achieve these results, we interrogate simulated and real tracking data with the explicit purpose of drawing attention to the key considerations in the use and interpretation of inference methods and their impact on resultant social structure. We provide a modified translation of the GMMEvents method for R, including new analyses quantifying the directionality and duration of social events with the aim of encouraging the careful use of these methods more widely in less tractable social animal systems but where passive telemetry is already widespread.
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