Allometry, the scaling of traits or biological rates with body mass, is central to a wide range of ecological research including dynamic food web modelling. There has been extensive focus on exponents (3/4 scaling laws), but little on the coefficients (normalisation constants). Coefficients that have been used since 2006 are derived from limited data and dated methodologies. Here, we compiled a data set of over 1000 genera with body mass spanning 10 orders of magnitude. We updated metabolism and production coefficients, deriving new genus and metabolic group levels estimates with phylogenetic hierarchical modelling providing robust inference. Our coefficients were mostly lower than those previously estimated, with increased uncertainty estimates. We used the Bioenergetic Food Web Model to evaluate their impact, finding increased biomass and species persistence but no change in stability. Our coefficients pave the way for future simulations that take advantage of subsets of genus and metabolic group data.

ABSTRACT Demographic risks from climate change remain poorly understood for megaherbivore species which face unique challenges because their large food requirements impose strong bottom-up limitation while their small surface-area-to-volume ratio limits heat dissipation. Here, we test how megaherbivore mortality is shaped by the concurrent effects of temperature and rainfall along with vegetation productivity, a potentially critical modifier of climate effects. By analysing four decades of monthly mortality records from 4,457 semi-captive Asian elephants across Myanmar, we identify multiple environmental pathways regulating megaherbivore mortality. Elephant mortality increased at extreme hot and cold temperatures in regions with low annual vegetation productivity, whereas high vegetation productivity buffered against such U-shaped effects of temperature. Furthermore, high rainfall amplified the negative impacts of extreme heat, underlining risks arising from the joint effects of heat and humidity. Seasonal declines in vegetation productivity did not explain the elevated mortality at temperature extremes. Together, our findings show that megaherbivores face elevated risks from global warming, but such risks strongly depend on vegetation productivity and humidity, highlighting multiple pathways through which climate change can shape the dynamics of megaherbivore populations.

Anticipating population declines is a crucial goal of conservation ecology. Recent conceptual work suggests that populations facing growing stressors should exhibit sequential shifts in behavior, morphology, and abundance before declining to extinction. However, the lack of high-resolution, multidimensional data has hindered empirical validation of this conceptual work. Using an autonomously monitored, high-throughput experimental system, we generated individual-based data on populations of the ciliate Paramecium caudatum forced to collapse due to increasingly stressful conditions. The gradual introduction of a pollutant elicited the predictable sequence of responses-declines in movement speed, followed by declines in body length, emergence of early warning signals of collapse, and finally, abundance declines. Conversely, a press disturbance generated by the introduction of predators did not induce this sequence. The time between the first detectable trait changes and population collapse depended on the statistical approach used, but the sequence remained consistent. Using general additive models, detectable behavioral signals in the polluted populations occurred one generation before abundance-based early warning signals were detectable, and two generations before abundance decline. We highlight that multivariate monitoring, particularly individual-based metrics, is crucial for forecasting population declines.

1. Steroid hormones, especially glucocorticoids (GCs), are widely used to assess physiological responses to stressors. As steroid hormones are heavily metabolised prior to excretion, it is essential to validate enzyme immunoassays (EIAs) for measuring faecal glucocorticoid metabolites (fGCMs). Although problems with unvalidated assays have been raised repeatedly, their use persists widely. 2. Lea et al. (2017) used an unvalidated corticosterone assay (CJM006) to relate fGCM concentrations to habitat quality, demography and population performance in the Cape mountain zebra (Equus zebra zebra). Here, we revisit their findings and evaluate the validity of their conclusions using a validated EIA. First, we evaluate the biological sensitivity of six EIAs (three group-specific metabolite assays and three corticosterone assays, including CJM006) through a biological validation experiment (translocation) for two sub-species of mountain zebra, Cape mountain and Hartmann's mountain zebra (E. z. hartmannae). Second, we reanalyse the faecal extracts from Lea et al. (2017) using a validated EIA. 3. fGCM concentrations consistently increased following translocation, when using two 11-oxoaetiocholanolone (lab codes: 72T and 72a) and an 11 ss-hydroxyaetiocholanolone (69a) EIA, but did not with three different corticosterone EIAs. All corticosterone EIAs (including CJM006) failed to detect an increase in fGCMs within the critical 48-72-h period post translocation. Therefore, the CJM006 EIA utilised in Lea et al. (2017) does not sensitively measure hypothalamic-pituitary-adrenal (HPA) axis activity in CMZ faeces. 4. Using a validated assay (72T), fGCM concentrations were no longer associated with adult sex ratio or habitat quality (measured by grassiness) and these variables were dropped from predictive models. fGCM concentrations now varied between seasons and were negatively associated with female fecundity (foal:mare ratio). Consequently, we can conclude that the results of the previous study are unreliable. 5. We introduce the terms "insensitive" and "sub-optimal" to categorise assays that are tested but fail validation, and assays that are comparatively poor at detecting relevant hormone changes, respectively. We discuss how both "insensitive" and "sub-optimal" assays could lead to incorrect inferences about population stressors and counterproductive conservation recommendations. Read the free Plain Language Summary for this article on the Journal blog.

Grasslands, which encompass 40% of terrestrial ecosystems, hold global significance for food production, carbon storage and other ecosystem services. However, grasslands across the biosphere are becoming increasingly exposed to both wet and dry precipitation extremes resulting from climate change. Therefore, understanding how grasslands will respond to precipitation extremes is a pressing issue for managing changes to biodiversity and ecosystem service provision. Here, we use experimental manipulations of precipitation (50% increase and 50% decrease in growing-season precipitation) over 6 years to investigate the stability and resistance of both productivity and community diversity in a calcareous grassland community. We found that decreased growing-season precipitation led to reductions in mean productivity (25% decrease in peak above-ground biomass) and its temporal stability (54% increase in the coefficient of variation of biomass across years). Productivity losses were more pronounced for graminoids and legumes, but this was not reflected in species per cent cover. Community composition was resistant to the precipitation manipulations, with no clear differences in overall community compositional turnover, dissimilarity or biodiversity indices. There was also no detectible effect of increased precipitation on productivity or community composition, which may indicate a lack of efficacy of the irrigation treatment in increasing soil moisture. Finally, the precipitation manipulations had no effect on temporal trends of community change, with an overall increase in richness and shift in grassland community composition across the study period independent of treatment. Synthesis. While the diversity and composition of this calcareous grassland was resistant to precipitation extremes (at least in the short term), sustained reductions in growing-season precipitation reduced productivity and its temporal stability, particularly for graminoids and legumes. Therefore, we highlight that different properties of grasslands can vary in their responses to changes in precipitation. While the diversity and composition of this calcareous grassland was resistant to precipitation extremes (at least in the short term), sustained reductions in growing-season precipitation reduced productivity and its temporal stability, particularly for graminoids and legumes. Therefore, the authors highlight that different properties of grasslands can vary in their responses to changes in precipitation.image

Recent population recovery of many pinniped species (seals, sea lions, walrus) is a conservation success. However, pinniped population recovery combined with increasing global fisheries operations is leading to increased conflicts between pinnipeds and fisheries. This human-wildlife conflict threatens pinniped conservation outcomes and may impose damaging impacts on fisheries, but the economic consequences and extent of these impacts are poorly understood. Here, we provide a global assessment of pinniped and fisheries operational interactions. We show that a third of reported fishing days have interactions with pinnipeds and 13.8% of catch is lost. Our results also reveal high heterogeneity between studies. Small-scale fisheries are three times more likely to interact with pinnipeds and lose four times as much catch as large-scale fisheries. Finally, we develop a spatial index that can predict where conflict is most likely to occur. Our findings reveal a substantial global issue requiring appropriate management as pinniped populations continue to recover.

We describe a challenging robotics deployment in a complex ecosystem to monitor a rich plant community. The study site is dominated by dynamic grassland vegetation and is thus visually ambiguous and liable to drastic appearance change over the course of a day and especially through the growing season. This dynamism and complexity in appearance seriously impact the stability of the robotics platform, as localisation is a foundational part of that control loop, and so routes must be carefully taught and retaught until autonomy is robust and repeatable. Our system is demonstrated over a 6-week period monitoring the response of grass species to experimental climate change manipulations. We also discuss the applicability of our pipeline to monitor biodiversity in other complex natural settings.

Extreme precipitation events are becoming more intense and frequent due to climate change. This climatic shift is impacting the structure and dynamics of natural communities and the key ecosystem services they provide. Changes in species abundance under these conditions are thought to be mediated by functional traits, morpho-physiological characteristics of an organism that impact its fitness. Future environmental conditions may, therefore, favour different traits to those in present-day communities. After 6 years of manipulated precipitation levels, including drought (-50% of ambient precipitation), irrigation (+50% of ambient precipitation), and control (ambient precipitation), we measured five key functional traits (plant height, leaf dry matter content [LDMC], leaf thickness, specific leaf area [SLA], and leaf phosphorus concentration) in 586 individual vascular plants to study the effects of precipitation changes on community-weighted functional traits. Additionally, we tested whether the precipitation change effects on the traits depend on the time of the growing season. As expected, reduced precipitation impacted community composition only for the late-season timing, after the seasonal field mowing, but led to a significant change in all community-level plant traits between season timings. Under drought, communities shifted towards shorter individuals with thicker but small leaves and lower phosphorous content. Overall, a combination of community reassembly and intraspecific variation contributed to community-weighted differences between control and drought plots for plant height, SLA, and LDMC traits. Species turnover was the main driver of community-weighted means (CWMs) shifts in all traits in the late-season but SLA. Whereas all traits showed variations at the community level with drought, SLA and LDMC were the most responsive traits at the species level. Nevertheless, our results suggest underestimation of intraspecific variation due to sensitive species lower abundance under stress. No differences in CWMs of functional traits were observed between control and irrigated plots. Synthesis: Our findings suggest that functional trait composition of grassland communities may shift under climate change-induced drought, depending on the growing season timings. Trait-based attempts to predict ecosystem functioning must account for such temporal variation in community trait values. Los eventos de precipitaci & oacute;n extrema est & aacute;n volvi & eacute;ndose m & aacute;s intensos y frecuentes debido al cambio clim & aacute;tico, lo que est & aacute; afectando la estructura y din & aacute;mica de las comunidades. Los cambios en la abundancia de especies bajo estas condiciones son mediados por rasgos funcionales, caracter & iacute;sticas morfo-fisiol & oacute;gicas de los organismos que afectan su eficacia biol & oacute;gica. Por eso, las condiciones ambientales futuras podr & iacute;an favorecer rasgos funcionales diferentes a los de las comunidades actuales. Despu & eacute;s de seis a & ntilde;os manipulando los niveles de precipitaci & oacute;n con: sequia (-50% precipitaci & oacute;n ambiental), irrigaci & oacute;n (+50% precipitaci & oacute;n ambiental) y control (precipitaci & oacute;n ambiental), medimos cinco rasgos funcionales clave (altura de la planta, contenido seco foliar - LDMC -, grueso foliar, peso espec & iacute;fico foliar - SLA - y concentraci & oacute;n foliar de f & oacute;sforo) en 586 plantas vasculares para estudiar el efecto de la precipitaci & oacute;n en las medias ponderadas en la comunidad de rasgos funcionales. Adem & aacute;s, testeamos si el cambio en los rasgos funcionales con la precipitaci & oacute;n depende del momento de la temporada de crecimiento. La reducci & oacute;n de la precipitaci & oacute;n cambi & oacute; la composici & oacute;n de la comunidad en la etapa tard & iacute;a de la temporada, despu & eacute;s del corte estacional, pero provoc & oacute; cambios en los rasgos funcionales a nivel de comunidad en los dos momentos de la temporada. Con la sequ & iacute;a las comunidades de pastizal mostraron individuos m & aacute;s bajos, con hojas gruesas pero peque & ntilde;as y con menos f & oacute;sforo. Una combinaci & oacute;n de cambios en la comunidad y variabilidad intraespec & iacute;fica contribuy & oacute; a las diferencias entre medias ponderadas por la comunidad entre control y sequ & iacute;a en altura de la planta, SLA y LDMC. El recambio de especies fue el principal responsable de los cambios al final de la temporada en todos los rasgos excepto SLA. Mientras que observamos cambios a nivel de comunidad con la sequ & iacute;a en todos los rasgos medidos, SLA y LDMC fueron los m & aacute;s sensibles a nivel de especie. No obstante, nuestros resultados sugieren una subestimaci & oacute;n de la variabilidad intraespec & iacute;fica debido a la menor abundancia de las especies m & aacute;s sensibles bajo estr & eacute;s. No se observaron diferencias entre los tratamientos de control e irrigaci & oacute;n. S & iacute;ntesis: Nuestros resultados sugieren que la composici & oacute;n de rasgos funcionales de las comunidades puede cambiar bajo la sequ & iacute;a. La variaci & oacute;n temporal debe ser considerada para predecir el funcionamiento de los ecosistemas en el contexto de cambio clim & aacute;tico. These findings suggest that functional trait composition of grassland communities may shift under climate change-induced drought, depending on the growing season timings. Trait-based attempts to predict ecosystem functioning must account for such temporal variation in community trait values.image

Extreme precipitation events are expected to become more intense and frequent with climate change. This climatic shift may impact the structure and dynamics of natural communities and the key ecosystem services they provide. Changes in species abundance under these extreme conditions are thought to be driven by functional traits, morpho-physiological characteristics of an organism that impact its fitness. Future environmental conditions may, therefore, favour different functional traits to those in present-day communities. Here, we measure functional traits on 586 vascular plants in a temperate grassland where precipitation has been experimentally manipulated for six years. We calculated community-weighted means of five functional traits (plant height, leaf dry matter content, leaf thickness, specific leaf area, and leaf phosphorus concentration) and compared community-weighted means between three levels of precipitation: drought (−50%), irrigated (+50%), and control. Additionally, we contrasted treatments at two different timings along the growing season: mid-season and late-season. We expected altered community-weighted means for traits associated with a conservative use of water that will result from increased summer stress-induced intraspecific variability in the mid-season and from community composition changes in the late-season, after the field is cut, a common management action across most European grasslands. In the drought treatment, we found significantly lower community-weighted mean plant height and leaf dry matter content. However, we only observed these differences after the mid-season cut. We also observed an increase in leaf phosphorus concentration in the drought treatment before the mid-season cut. A combination of changes in community composition and intraspecific variation contributed to these differences, with community composition being more important after the cut. Species with higher height, leaf dry matter content, and lower leaf thickness showed a more pronounced abundance decline at the drought plots. We observed no changes in functional traits community-weighted means in the irrigated treatment compared to those in control and drought treatments. Synthesis . Our results suggest how the functional trait composition of grassland communities may shift under climate change-induced drought, stressing the interacting effects with growing season stages.

Despite exponential growth in ecological data availability, broader interoperability amongst datasets is needed to unlock the potential of open access. Our understanding of the interface of demography and functional traits is well-positioned to benefit from such interoperability. Here, we introduce MOSAIC, an open-access trait database that unlocks the demographic potential stored in the COMADRE, COMPADRE, and PADRINO open-access databases. MOSAIC data were digitised and curated through a combination of existing datasets and new trait records sourced from primary literature. In its first release, MOSAIC (v. 1.0.0) includes 14 trait fields for 300 animal and plant species: biomass, height, growth determination, regeneration, sexual dimorphism, mating system, hermaphrodism, sequential hermaphrodism, dispersal capacity, type of dispersal, mode of dispersal, dispersal classes, volancy, and aquatic habitat dependency. MOSAIC includes species-level phylogenies for 1,359 species and population-specific climate data. We identify how database integration can improve our understanding of traits well-quantified in existing repositories and those that are poorly quantified (e.g., growth determination, modularity). MOSAIC highlights emerging challenges associated with standardising databases and demographic measures.

The global recovery of pinniped populations is a conservation success. However, pinniped population recovery has increased human-wildlife conflict with fisheries, an issue often reported and requiring management, but one that lacks global synthesis. We conduct a meta-analysis to estimate the impacts of operational interactions (specifically, lost catch) between pinnipeds and fisheries. Where quantifiable interactions are reported (n = 36), on average fishers have a 33.7% chance of interacting with pinnipeds on any given fishing day, and 13.8% lost catch. We find a large degree of heterogeneity between studies, with some fisheries experiencing much more negative interactions than others. Specifically, smaller-scale fisheries using nets are up to twice as likely to have negative interactions and lose up to five times more catch compared to large-scale fisheries. We conclude that pinniped-fishery conflict is a substantial global issue, but its impacts are not uniform. To successfully manage long-term coexistence between pinnipeds and humans, explicit data quantifying operational interactions is required. Population recoveries can have unintended consequences for fisheries, and management of ecological, social and economic outcomes is needed for long-term coexistence. Teaser Pinniped population recoveries have led to significant impacts on fisheries, but small-scale fisheries lose out most.

Although social behaviour is common in group-living mammals, our understanding of its mechanisms in long-lived animals is largely based on studies in human and non-human primates. There are health and fitness benefits associated with strong social ties, including increased life span, reproductive success, and lower disease risk, which are attributed to the proximate effects of lowered circulating glucocorticoid hormones. However, to deepen our understanding of health-social dynamics, we must explore species beyond the primate order. Here, using Asian elephants as a model species, we combine social data generated from semi-captive timber elephants in Myanmar with measurements of faecal glucocorticoid metabolite (FGM) concentrations. These data enable a "natural experiment" because individuals live in work groups with different demographic compositions. We examine sex-specific FGM concentrations for four different aspects of an individuals' social world: general sociality, work group size, sex ratio and the presence of immatures (<5 years) within the work group. Males experienced lower FGM concentrations when engaged in more social behaviours and residing in female-biased work groups. Surprisingly, females only exhibited lower FGM concentrations when residing with calves. Together, our findings highlight the importance of sociality on individual physiological function among elephants, which may have broad implications for the benefits of social interactions among mammals.

Image sensing technologies are rapidly increasing the cost-effectiveness of biodiversity monitoring efforts. Species differences in the reflectance of electromagnetic radiation have recently been highlighted as a promising target to estimate plant biodiversity using multispectral image data. However, these efforts are currently hampered by logistical difficulties in broad-scale implementation and their use in characterizing biodiversity at different spatial scales. Here, we investigate the utility of multispectral imaging technology from commercially available unmanned aerial vehicles (UAVs, or drones) in estimating biodiversity metrics at short-range (<10 m image recording height) in a temperate calcareous grassland ecosystem in Oxfordshire, UK. We calculate a suite of moments (coefficient of variation, standard deviation, skew, kurtosis) for the distribution of radiance from multispectral images at five wavelength bands (Blue 450±16 nm; Green 560±16 nm; Red 650±16 nm; Red Edge 730±16 nm; Near Infrared 840±16 nm) and test their effectiveness at estimating ground-truthed biodiversity metrics from in-situ botanical surveys for 37 - 1 m × 1 m quadrats. We find positive associations between the average coefficient of variation in spectral radiance and both the Shannon-Weiner and Simpsons biodiversity indices. Furthermore, we find that the average coefficient of variation in spectral radiance is consistent and highly repeatable, across sampling days and recording heights. Positive associations with biodiversity indices hold irrespective of the image recording height (2-8 m), but we report reductions in estimates of spectral diversity with increases to UAV recording height. UAV imaging reduced sampling time by 16-fold relative to in-situ botanical surveys. Synthesis - We demonstrate the utility of multispectral radiance moments as an indicator of grassland biodiversity metrics at high spatial resolution using a widely available UAV monitoring system at a coarse spectral resolution. The use of UAV technology with multispectral sensors has far-reaching potential to provide cost-effective and high-resolution monitoring of biodiversity in complex environments.

Variation in individual demographic rates can have large consequences for populations. Female reproductive skew is an example of structured demographic heterogeneity where females have intrinsic qualities that make them more or less likely to breed. The consequences of reproductive skew for population dynamics are poorly understood in non-cooperatively breeding mammals, especially when coupled with other drivers such as poaching. We address this knowledge gap with population viability analyses using an age-specific, female-only, individual-based, stochastic population model built with long-term data for three Kenyan populations of the Critically Endangered eastern black rhino (Diceros bicornis michaeli). There was substantial reproductive skew, with a high proportion of females not breeding or doing so at very low rates. This had a large impact on the projected population growth rate for the smaller population on Ol Jogi. Moreover, including female reproductive skew exacerbates the effects of poaching, increasing the probability of extinction by approximately 70% under a simulated poaching pressure of 5% offtake per year. Tackling the effects of reproductive skew depends on whether it is mediated by habitat or social factors, with potential strategies including habitat and biological management respectively. Investigating and tackling reproductive skew in other species requires long-term, individual-level data collection.

SummaryMatrix population models (MPMs) are an important tool for biologists seeking to understand the causes and consequences of variation in vital rates (e.g., survival, reproduction) across life cycles. Empirical MPMs describe the age- or stage-structured demography of organisms and usually represent the life history of a population during a particular time frame at a specific geographic location.The COMPADRE Plant Matrix Database and COMADRE Animal Matrix Database are the most extensive resources for MPM data, collectively containing >12,000 individual projection matrices for >1,100 species globally. Although these databases represent an unparalleled resource for researchers, land managers, and educators, the current computational tools available to answer questions with MPMs impose significant barriers to potential COM(P)ADRE database users by requiring advanced knowledge to handle diverse data structures and program custom analysis functions.To close this knowledge gap, we present two interrelated R packages designed to (i) facilitate the use of these databases by providing functions to acquire, quality control, and manage both the MPM data contained in COMPADRE and COMADRE, and a user’s own MPM data (Rcompadre), and (ii) present a range of functions to calculate life history traits from MPMs in support of ecological and evolutionary analyses (Rage). We provide examples to illustrate the use of both.Rcompadre and Rage will facilitate demographic analyses using MPM data and contribute to the improved replicability of studies using these data. We hope that this new functionality will allow researchers, land managers, and educators to unlock the potential behind the thousands of MPMs and ancillary metadata stored in the COMPADRE and COMADRE matrix databases, and in their own MPM data.

With the looming threat of abrupt ecological disruption due to a changing climate, predicting which species are most vulnerable to environmental change is critical. The life-history of a species is an evolved response to its environmental context, and therefore a promising candidate for explaining differences in climate-change responses. However, we need broad empirical assessments from across the world's ecosystems to explore the link between life history and climate-change responses. Here, we use long-term abundance records from 157 species of terrestrial mammals and a two-step Bayesian meta-regression framework to investigate the link between annual weather anomalies, population growth rates, and species-level life history. Overall, we found no directional effect of temperature or precipitation anomalies or variance on annual population growth rates. Furthermore, population responses to weather anomalies were not predicted by phylogenetic covariance, and instead there was more variability in weather responses for populations within a species. Crucially, however, long-lived mammals with smaller litter sizes had smaller absolute population responses to weather anomalies compared with their shorter living counterparts with larger litters. These results highlight the role of species-level life history in driving responses to the environment.

AbstractIn Focus:Culina, A., Adriaensen, F., Bailey, L. D., et al. (2021) Connecting the data landscape of long‐term ecological studies: The SPI‐Birds data hub.Journal of Animal Ecology,https://doi.org/10.1111/1365‐2656.13388. Long‐term, individual‐based datasets have been at the core of many key discoveries in ecology, and calls for the collection, curation and release of these kinds of ecological data are contributing to a flourishing open‐data revolution in ecology. Birds, in particular, have been the focus of international research for decades, resulting in a number of uniquely long‐term studies, but accessing these datasets has been historically challenging. Culina et al. (2021) introduce an online repository of individual‐level, long‐term bird records with ancillary data (e.g. genetics), which will enable key ecological questions to be answered on a global scale. As well as these opportunities, however, we argue that the ongoing open‐data revolution comes with four key challenges relating to the (1) harmonisation of, (2) biases in, (3) expertise in and (4) communication of, open ecological data. Here, we discuss these challenges and how key efforts such as those by Culina et al. are using FAIR (Findable, Accessible, Interoperable and Reproducible) principles to overcome them. The open‐data revolution will undoubtedly reshape our understanding of ecology, but with it the ecological community has a responsibility to ensure this revolution is ethical and effective.

Many mammals grow up with siblings, and interactions between them can influence offspring phenotype and fitness. Among these interactions, sibling competition between different-age offspring should lead to reproductive and survival costs on the younger sibling, while sibling cooperation should improve younger sibling's reproductive potential and survival. However, little is known about the consequences of sibling effects on younger offspring life-history trajectory, especially in long-lived mammals. We take advantage of a large, multigenerational demographic dataset from semi-captive Asian elephants to investigate how the presence and sex of elder siblings influence the sex, survival until 5 years old, body condition, reproductive success (i.e. age at first reproduction and lifetime reproductive success) and long-term survival of subsequent offspring. We find that elder siblings have heterogeneous effects on subsequent offspring life-history traits depending on their presence, their sex and the sex of the subsequent offspring (named focal calf). Overall, the presence of an elder sibling (either sex) strongly increased focal calf long-term survival (either sex) compared to sibling absence. However, elder sisters had higher impact on the focal sibling than elder brothers. Focal females born after a female display higher long-term survival, and decreased age at first reproduction when raised together with an elder sister rather than a brother. Focal males born after a female rather than a male showed lower survival but higher body weight when both were raised together. We did not detect any sibling effects on the sex of the focal calf sex, survival until 5 years old and lifetime reproductive success. Our results highlight the general complexity of sibling effects, but broadly that elder siblings can influence the life-history trajectory of subsequent offspring. We also stress the importance of considering all life stages when evaluating sibling effects on life trajectories.

In this article we present a standardized dataset on 6659 songbirds (Passeriformes) highlighting information relevant to species conservation prioritization with a main focus to support the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Data were collected from both scientific and grey literature as well as several online databases. The data are structured into six knowledge categories: Conventions and Treaties, Human Use, Extinction Risk, Management Opportunities, Biological Information, and Intrinsic Values. The Conventions and Treaties category includes the listings for two international conventions, CITES and the Convention on the Conservation of Migratory Species of Wild Animals (CMS), as well as EU listings for the EU Wildlife Trade Regulations and the EU Birds Directive. The Human Use category contains information on both regulated trade collected from the CITES Trade Database and the United States’ Law Enforcement Management Information System (LEMIS), and highly aggregated data on seizures which we obtained from TRAFFIC, the United Nations Office on Drugs and Crime (UNODC) and two data sources on traditional medicine. We also present, for the first time, the complete Songbirds in Trade Database (SiTDB), a trade database curated by taxon expert S. Bruslund based on expert knowledge, literature review, market surveys and sale announcements. Data on the types of human use, including traditional medicine are also provided. The knowledge area on Extinction Risk contains data on the species’ IUCN Red List status, the Alliance for Zero Extinction Trigger Species status, site and population at the site, the species’ IUCN Climate Change Vulnerability Assessment, and the listing of priority species at the Asian Songbird Crisis Summit. In the Management Opportunities category, we gathered data on ex-situ management from Species360 zoo holdings as well as species management plans from the European and North American Zoo Associations (EAZA and AZA, respectively). Biological Information includes data on body mass, clutch size, diet, availability of data from the IUCN Red List on habitat systems, extent of occurrence, generation length, migration pattern, distribution, and biological data from the Demographic Species Knowledge Index, number of occurrences recorded by the Global Biodiversity Information Facility (GBIF) as well as genomic data from the Bird 10 000K Genomes (B10K) project, Vertebrate Genome Project (VGP) and GenBank. Information on invasive species is also part of this knowledge area. The Intrinsic Value category refers to two measures of the species’ intrinsic value, namely Ecological and Evolutionary Distinctiveness. In order to make these knowledge areas comparable, we standardized data following the taxonomy of the Handbook of the Birds of the World and Birdlife (Version 4, 2019). The data enable a broad spectrum of analyses and will be useful to scientists for further research and to policymakers, zoos and other conservation stakeholders for future prioritization decisions.