Recognizability bias in citizen science photographs

Citizen science and automated collection methods increasinglydepend on image recognition to provide the amountsof observational data research and management needs.Recognition models, meanwhile, also require large amounts ofdata from these sources, creating a feedback loop between themethods and tools. Species that are harder to recognize, bothfor humans and machine learning algorithms, are likely to beunder-reported, and thus be less prevalent in the trainingdata. As a result, the feedback loop may hamper trainingmostly for species that already pose the greatest challenge. Inthis study, we trained recognition models for various taxa, andfound evidence for a‘recognizability bias’, where species thatare more readily identified by humans and recognitionmodels alike are more prevalent in the available image data.This pattern is present across multiple taxa, and does notappear to relate to differences in picture quality, biologicaltraits or data collection metrics other than recognizability. Thishas implications for the expected performance of futuremodels trained with more data, including such challenging species. citizen science, image recognition, machinelearning, recognizability, artificial intelligence/environmental science/ecology, Ecology, conservation and global change biologypublishedVersio

Life-history attributes and resource dynamics determine intraspecific home-range sizes in Carnivora

Home ranges capture a fundamental aspect of animal ecology, resulting from interactions between metabolic demands and resource availability. Yet, the understanding of their emergence is currently limited by lack of consideration of the covariation between intrinsic and extrinsic drivers. We analysed intraspecific home-range size (HRS) variation with respect to life histories and remotely sensed proxies of resource dynamics for 21 Carnivora species. Our best model explained over half of the observed variability in intraspecific HRS across populations of multiple species. At the species level, median HRS was smaller for omnivorous species and increased with increasing body mass (model R2 = 0.66). Here, HRS scaled with body mass at 0.80, a value much closer to the expected allometric scaling of 0.75 than previously reported. At the intraspecific level, while much variation was driven by intrinsic factors (body mass, diet, social organization and sex; R2 = 0.39), inclusion of spatiotemporal variation in extrinsic factors (average resource availability and seasonality) enabled explanation of a further 13% of observed variability in HRS. We found no evidence for interactions between intrinsic and extrinsic HRS drivers, suggesting a generally ubiquitous influence of resource availability on space-use. Our findings illustrate how spatial and temporal information on resource dynamics as derived by satellite data can significantly improve our understanding of HRS variation at the interspecific and intraspecific levels, and urge caution in interpreting HRS allometry in the face of large intraspecific variation. Moreover, our results highlight the importance of considering life-history constraints in modelling intraspecific space-use and HRS

Life-history attributes and resource dynamics determine intraspecific home-range sizes in Carnivora

Home ranges capture a fundamental aspect of animal ecology, resulting from interactions between metabolic demands and resource availability. Yet, the understanding of their emergence is currently limited by lack of consideration of the covariation between intrinsic and extrinsic drivers. We analysed intraspecific home-range size (HRS) variation with respect to life histories and remotely sensed proxies of resource dynamics for 21 Carnivora species. Our best model explained over half of the observed variability in intraspecific HRS across populations of multiple species. At the species level, median HRS was smaller for omnivorous species and increased with increasing body mass (model R2 = 0.66). Here, HRS scaled with body mass at 0.80, a value much closer to the expected allometric scaling of 0.75 than previously reported. At the intraspecific level, while much variation was driven by intrinsic factors (body mass, diet, social organization and sex; R2 = 0.39), inclusion of spatiotemporal variation in extrinsic factors (average resource availability and seasonality) enabled explanation of a further 13% of observed variability in HRS. We found no evidence for interactions between intrinsic and extrinsic HRS drivers, suggesting a generally ubiquitous influence of resource availability on space-use. Our findings illustrate how spatial and temporal information on resource dynamics as derived by satellite data can significantly improve our understanding of HRS variation at the interspecific and intraspecific levels, and urge caution in interpreting HRS allometry in the face of large intraspecific variation. Moreover, our results highlight the importance of considering life-history constraints in modelling intraspecific space-use and HRS

Spørreundersøkelse blant rypejegere i Lierne 2018

Som en del av prosjektet "Bærekraftig småvilforvaltning som grunnlag for lokal verdiskaping" omhandler denne rapporten svar på spørsmål gitt til rypejegere som enten hadde søkt på jakt i Lierne eller jaktet der i perioden 2013-2017. Spørsmålene som ble stilt spesifikt til personer som hadde jaktet rype i Lierne, var en tilleggsdel i en større nasjonal Rypejegerundersøkelse. Spørsmålene om Lierne omhandlet tema som motiver for å jakte rype i Lierne, informasjon om og tilrettelegging for rypejakt i kommunen, eventuelle konflikter med andre brukergrupper, tilleggsaktiviteter eller -tjenester i Lierne som kan være av interesse for rypejegeren, samt forhold ved uttak av jaktbart smårovvilt

Harvest Regulations and Implementation Uncertainty in Small Game Harvest Management

A main challenge in harvest management is to set policies that maximize the probability that management goals are met. While the management cycle includes multiple sources of uncertainty, only some of these has received considerable attention. Currently, there is a large gap in our knowledge about implemention of harvest regulations, and to which extent indirect control methods such as harvest regulations are actually able to regulate harvest in accordance with intended management objectives. In this perspective article, we first summarize and discuss hunting regulations currently used in management of grouse species (Tetraonidae) in Europe and North America. Management models suggested for grouse are most often based on proportional harvest or threshold harvest principles. These models are all built on theoretical principles for sustainable harvesting, and provide in the end an estimate on a total allowable catch. However, implementation uncertainty is rarely examined in empirical or theoretical harvest studies, and few general findings have been reported. Nevertheless, circumstantial evidence suggest that many of the most popular regulations are acting depensatory so that harvest bag sizes is more limited in years (or areas) where game density is high, contrary to general recommendations. A better understanding of the implementation uncertainty related to harvest regulations is crucial in order to establish sustainable management systems. We suggest that scenario tools like Management System Evaluation (MSE) should be more frequently used to examine robustness of currently applied harvest regulations to such implementation uncertainty until more empirical evidence is available

Quantifying the checks and balances of collaborative governance systems for adaptive carnivore management

Recovering or threatened carnivore populations are often harvested to minimise their impact on human activities, such as livestock farming or game hunting. Increasingly, harvest quota decisions involve a set of scientific, administrative and political institutions operating at national and sub-national levels whose interactions and collective decision-making aim to increase the legitimacy of management and ensure population targets are met. In practice, however, assessments of how quota decisions change between these different actors and what consequences these changes have on population trends are rare. We combine a state-space population modelling approach with an analysis of quota decisions taken at both regional and national levels between 2007 and 2018 to build a set of decision-making models that together predict annual harvest quota values for Eurasian lynx (Lynx lynx) in Norway. We reveal a tendency for administrative decision-makers to compensate for consistent quota increases by political actors, particularly when the lynx population size estimate is above the regional target. Using population forecasts based on the ensemble of decision-making models, we show that such buffering of political biases ensures lynx population size remains close to regional and national targets in the long term. Our results go beyond the usual qualitative assessment of collaborative governance systems for carnivore management, revealing a system of checks and balances that, in the case of lynx in Norway, ensures both multi-stakeholder participation and sustainable harvest quotas. Nevertheless, we highlight important inter-regional differences in decision-making and population forecasts, the socio-ecological drivers of which need to be better understood to prevent future population declines. Synthesis and applications. Our work analyses the sequence of decisions leading to yearly quotas for lynx harvest in Norway, highlighting the collaborative and structural processes that together shape harvest sustainability. In doing so, we provide a predictive framework to evaluate participatory decision-making processes in wildlife management, paving the way for scientists and decision-makers to collaborate more widely in identifying where decision biases might lie and how institutional arrangements can be optimised to minimise them. We emphasise, however, that this is only possible if wildlife management decisions are documented and transparent

GMSE: an R package for generalised management strategy evaluation

1. Management strategy evaluation (MSE) is a powerful tool for simulating all key aspects of natural resource management under conditions of uncertainty. 2. We present the R package GMSE, which applies genetic algorithms to provide a generalised tool for simulating adaptive decision‐making management scenarios between stakeholders with competing objectives under complex social‐ecological interactions and uncertainty. 3. GMSE models can be agent‐based and spatially explicit, incorporating a high degree of realism through mechanistic modelling of links and feedbacks among stakeholders and with the ecosystem; additionally, user‐defined sub‐models can also be incorporated as functions into the broader GMSE framework. 4. We show how GMSE simulates a social‐ecological system using the example of an adaptively managed waterfowl population on an agricultural landscape; simulated waterfowl exploit agricultural land, causing conflict between conservation interests and the interest of food producers maximising their crop yield. 5. The R package GMSE is open source under GNU Public License; source code and documents are freely available on GitHub

Quantifying the checks and balances of collaborative governance systems for adaptive carnivore management

1. Recovering or threatened carnivore populations are often harvested to minimise their impact on human activities, such as livestock farming or game hunting. Increasingly, harvest quota decisions involve a set of scientific, administrative and political institutions operating at national and sub-national levels whose interactions and collective decision-making aim to increase the legitimacy of management and ensure population targets are met. In practice, however, assessments of how quota decisions change between these different actors and what consequences these changes have on population trends are rare. 2. We combine a state-space population modelling approach with an analysis of quota decisions taken at both regional and national levels between 2007 and 2018 to build a set of decision-making models that together predict annual harvest quota values for Eurasian lynx (Lynx lynx) in Norway. 3. We reveal a tendency for administrative decision-makers to compensate for consistent quota increases by political actors, particularly when the lynx population size estimate is above the regional target. Using population forecasts based on the ensemble of decision-making models, we show that such buffering of political biases ensures lynx population size remains close to regional and national targets in the long term. 4. Our results go beyond the usual qualitative assessment of collaborative governance systems for carnivore management, revealing a system of checks and balances that, in the case of lynx in Norway, ensures both multi-stakeholder participation and sustainable harvest quotas. Nevertheless, we highlight important inter-regional differences in decision-making and population forecasts, the socio-ecological drivers of which need to be better understood to prevent future population declines. 5. Synthesis and applications. Our work analyses the sequence of decisions leading to yearly quotas for lynx harvest in Norway, highlighting the collaborative and structural processes that together shape harvest sustainability. In doing so, we provide a predictive framework to evaluate participatory decision-making processes in wildlife management, paving the way for scientists and decision-makers to collaborate more widely in identifying where decision biases might lie and how institutional arrangements can be optimised to minimise them. We emphasise, however, that this is only possible if wildlife management decisions are documented and transparent

Assessment of the risk to Norwegian biodiversity from import and keeping of crustaceans in freshwater aquaria

Introduction The Norwegian Scientific Committee for Food and Environment (VKM) was requested by the Norwegian Environment Agency to assess the risk of negative impacts to biodiversity in Norway resulting from import of crustacean decapods for keeping in freshwater aquariums. VKM was asked to 1) list species of crayfish, crabs and shrimps that are currently kept in freshwater aquaria in Norway, and species that are likely to be kept in freshwater aquaria in Norway within the next 10 years, 2) assess the ability of the species to survive under Norwegian conditions and cause impacts on ecosystems and other species, and 3) state the potential negative effects on the biological diversity of diseases caused by pathogens, regulated under the Norwegian Food Act.Methods The risk assessment, without focus on pathogens, was performed in two steps. First, we used a pre-screening toolkit to identify species of crayfish, crabs and shrimps with potential to become invasive in freshwater habitats in Norway. Each species was given an invasiveness score based on 55 questions on biogeography, ecology, and climate change. In a second step, a full risk assessment, including the potential impacts of pathogens, was conducted on those species receiving the highest invasiveness score. This assessment included questions on the organism’s probability of entry and pathways of entry, establishment and spread, potential impacts on biodiversity, and how climate change scenarios might affect the assessment. Likelyhood and confidence was assessed for each question. In conclusion, each species was designated as either low-, moderate-, or high risk. Many crustacean decapod species are confirmed or suspected carriers of pathogens that can cause mass mortality among native crustaceans. The risk posed by crustaceans as carriers of pathogens may be independent of the environmental risk that they pose through ecological interactions. Therefore, the four crustacean disease pathogens that are regulated under the Norwegian Food Act, were assessed separately. These include Aphanomyces astaci causing crayfish plague, white spot syndrome virus (WSSV) causing white spot disease, Taura syndrome virus (TSV) causing Taura syndrome, and yellow head virus genotype 1 (YHV1) causing yellow head disease. The assessments comprised questions on the pathogen’s probability of entry (as a hitchhiker organism with imported crustaceans), pathways of entry, establishment and spread, and potential impact on crustacean biodiversity. Likelihood and confidence were assessed for each question. In conclusion, each pathogen was designated as either low-, moderate-, or high risk.In a third step, we categorized the likelihood that a crustacean species introduces a pathogen associated with a high- or moderate risk into: I) known chronic carriers, II) suspected chronic carriers, III) suspected situational carrier, IV) possible pathogen transmitters, and V) no direct or circumstantial evidence for carrier status or pathogen transmission in the genus.Results Based on information from the Norwegian Pet Trade Association, the project group listed 112 taxa (mainly species and some genera) of freshwater crayfish, crabs and shrimps that are relevant for trade in Norway. These included 38 crayfish taxa, 28 crab taxa, and 45 shrimp taxa. In addition, one marine crab was included. Sixteen species of crayfish, four species of shrimps, and two species of crabs underwent a full ecological risk assessment. The probabilities of entry both into the aquarium trade in Norway, and potentially further into Norwegian nature, were based on the prevalence of the species in the aquarium trade in Norway. We assumed that all species were equally likely to escape captivity or to be released. The four pathogens regulated under the Norwegian Food Act are either known or potential hazards to biodiversity in Norway. A. astaci is already present in Norway. It is regarded among the greatest threats to European freshwater crayfish, including noble crayfish (Astacus astacus). American freshwater crayfish are either known or suspected chronic carriers of A. astaci, while several crayfish species from other continents, as well as some species of crab and shrimp, may be situational carriers. WSSV is a "non-exotic" list 2 disease. All decapods can be infected by the virus. WSSV is primarily a problem in shrimp farming in Asia, but has spread to America and more recently to Australia. WSSV can cause 100% mortality in noble crayfish at water temperatures above 20 °C. Both TSV and YHV1 are "exotic" list 1 diseases. These can infect and cause high mortality in a limited range of saltwater shrimps. There is no evidence that TSV and YHV1 pose a risk to freshwater crayfish in the Nordic climate, nor is introduction likely through aquarium trade in freshwater crustaceans. Several other pathogens that cause crustacean dirsease are listed by the World Organization for Animal Health (OIE). These were briefly assessed, but not fully risk assessed.Conclusions VKM concluded that the risk of negative impacts on biodiversity caused by ecological interactions following import and private keeping of crayfish is high for Faxonius virilis, Faxonius spp., Procambarus clarkii, P. virginalis, and Pacifastacus leniusculus. These species can displace native crayfish, reduce the abundance of aquatic plants, and cause cascading effects that negatively influence invertebrates, fish, and birds. They can likely establish in Norwegian nature under the current climate conditions. The risk of negative consequences is moderate (with medium confidence) for the crayfish Cambarellus patzcuarensis, Procambarus alleni, Creaserinus fodiens, Cambarellus montezumae, Cherax monticola, Cherax tenuimanus, Faxonius neglectus. Perconon gibbesi of the crabs and Neocaridina davidi and Macrobrachium rosenbergii of the shrimps were associated with a moderate risk with medium confidence. Species associated with medium risk are omnivorous keystone species that will have at least moderate ecological impact on littoral freshwater ecosystems (medium confidence) if established in dense populations. None of the species associated with medium risk are likely to establish today. However, climate change will increase the risk for establishment and resulting ecological impact. The risk for negative impacts caused by the crayfish plague pathogen Aphanomyces astaci is high with high confidence. Crayfish plague can cause up to 100% mortality, and has already eradicated several noble crayfish populations in Norway. For WSSV, the risk for negative impact is moderate with high confidence. The risks associated with TSV and YHV1 are assessed as low for Norwegian crustacean biodiversity. According to the risk assessment of pathogens and the categorization of crustacean species based on their likelihood of being carriers of A. astaci and WSSV, 25 and 13 species of crayfish are associated with a high and medium risk, respectively. Four and 25 species of crabs are associated with a medium and low risk, respectively, and 14 and 31 species of shrimps are associated with medium and low risk, respectively. Notably, all species in the named genera should be regarded as belonging to the given risk category. OIE and general literature provide information of known crustacean diseases along with known susceptible crustacean hosts. However, there is a lack of information regarding carrier status of known and unknown disease pathogens for many exotic crustaceans. In this perspective, all exotic crustaceans should be regarded as potentially infected with a known or unknown pathogen. In order to reduce the risk of spreading diseases, eggs and living or dead animals should under no circumstances be disposed of in nature. The same applies for aquarium water or any material, such as gravel or ornamental plants, that have been in contact with the animals or water in the aquarium. The current permit requirement exemption for import of freshwater organisms that can only survive at temperatures above 5 °C provides no protection against the introduction, establishment, and spread of accompanying pathogens that could cause mass mortality in Norwegian crustacean populations. Finally, we can never predict how, or from which host species, a new disease might emerge. Many pandemics and plagues result from cross-continental pathogen-host jumps often facilitated by human transport, trade, introduction, release, or escape of alien species and associated alien pathogens

ROBITT: a tool for assessing the risk-of-bias in studies of temporal trends in ecology

1. Aggregated species occurrence and abundance data from disparate sources are increasingly accessible to ecologists for the analysis of temporal trends in biodiversity. However, sampling biases relevant to any given research question are often poorly explored and infrequently reported; this can undermine statistical inference. In other disciplines, it is common for researchers to complete ‘risk-of-bias’ assessments to expose and document the potential for biases to undermine conclusions. The huge growth in available data, and recent controversies surrounding their use to infer temporal trends, indicate that similar assessments are urgently needed in ecology. 2. We introduce ROBITT, a structured tool for assessing the ‘Risk-Of-Bias In studies of Temporal Trends in ecology’. ROBITT has a similar format to its counterparts in other disciplines: it comprises signalling questions designed to elicit information on the potential for bias in key study domains. In answering these, users will define study inferential goal(s) and relevant statistical target populations. This information is used to assess potential sampling biases across domains relevant to the research question (e.g. geography, taxonomy, environment), and how these vary through time. If assessments indicate biases, then users must clearly describe them and/or explain what mitigating action will be taken. 3. Everything that users need to complete a ROBITT assessment is provided: the tool, a guidance document and a worked example. Following other disciplines, the tool and guidance document were developed through a consensus-forming process across experts working in relevant areas of ecology and evidence synthesis. 4. We propose that researchers should be strongly encouraged to include a ROBITT assessment when publishing studies of biodiversity trends, especially when using aggregated data. This will help researchers to structure their thinking, clearly acknowledge potential sampling issues, highlight where expert consultation is required and provide an opportunity to describe data checks that might go unreported. ROBITT will also enable reviewers, editors and readers to establish how well research conclusions are supported given a dataset combined with some analytical approach. In turn, it should strengthen evidence-based policy and practice, reduce differing interpretations of data and provide a clearer picture of the uncertainties associated with our understanding of reality