Limitations and Benefits of the Unmatched Count Technique: Considering How We Use New Methods in Conservation

Posted on January 9, 2019 by Chris Grieves

Post provided by Amy Hinsley and Ana Nuno

Esta publicação no blogue também está disponível em português

A New Conservation Toolbox

It is widely accepted that many conservation challenges are directly related to human behaviour. Whether it is the over-collection of a rare orchid by harvesters in Southeast Asia, or the decisions by collectors in Europe to buy and smuggle these orchids home, understanding the extent and nature of these behaviours is essential to addressing the threats they might cause. This has led conservation researchers and practitioners to start looking outside of their discipline, to find methods and approaches from across the social sciences to improve our understanding of these complex issues.

A research assistant carrying out a UCT survey about the use of Traditional Medicine products containing bear bile in China. © Chen Haochun.

While this interdisciplinarity is a positive move for conservation, it is important that we treat these ‘new’ methods carefully and understand their limitations. If we don’t, there is a risk that our new toolbox full of exciting methods that sound great on a funding application, may in fact not be making what we do any better, or in extreme cases they may even be making it worse.

With this in mind, a group of conservation social scientists, led by researchers at the Universities of Oxford and Exeter, decided to look in depth into one of these ‘new’ methods, to provide recommendations on when and how it should be used, and when it shouldn’t. Our Open Access article – ‘Asking sensitive questions using the unmatched count technique: Applications and guidelines for conservation‘ – looks at the Unmatched Count Technique (UCT – also called the list experiment), which is increasingly being used in conservation to ask questions about ‘sensitive’ topics. Continue reading →

Limitações e benefícios da técnica de contagem de itens: considerações sobre o uso de novos métodos em Conservação

Posted on January 9, 2019 by Chris Grieves

publicação no blogue FORNECIDO POR AMY HINSLEY E ANA NUNO

This blog post is also available in English

Novas ferramentas de conservação

Muitos desafios em conservação estão diretamente relacionados com o comportamento humano. Quer seja a recolha excessiva de uma orquídea rara no Sudeste Asiático, ou a compra e contrabando dessas orquídeas por colecionadores na Europa, entender a magnitude e a natureza desses comportamentos é essencial para lidar com as ameaças que eles podem causar. Isso levou os investigadores e profissionais da área de conservação a começarem a olhar para fora da sua própria disciplina, de modo a encontrar métodos e abordagens das ciências sociais para melhorar a nossa compreensão sobre estas questões complexas.

Assistente de investigação a realizar um estudo recorrendo a TCI sobre o uso de produtos de medicina tradicional com bílis de urso na China. © Chen Haochun.

Embora esta interdisciplinaridade seja um passo positivo para a conservação, é importante tratar esses “novos” métodos com cuidado e entender as suas limitações. Se não o fizermos, existe o risco da nossa nova caixa de ferramentas, repleta de métodos interessantes que soam bem em candidaturas a financiamento, na verdade não melhorar aquilo que nós geralmente já fazemos ou, em casos extremos, até piorá-lo.

Tendo isto em conta, um grupo de cientistas sociais em conservação, liderado por investigadores das Universidades de Oxford e Exeter, decidiu examinar em profundidade um desses “novos” métodos, fornecer recomendações sobre quando e como ele deveria ser usado, e quando não deveria. O artigo, disponível gratuitamente na revista científica Methods in Ecology and Evolution nesta semana, examina a Técnica de Contagem de Itens (TCI), que tem sido cada vez mais usada em conservação para fazer perguntas sobre tópicos “sensíveis”. Continue reading →

How to Assemble, Fill and Clean Metapopulation Microcosm Plates: Two Video Tutorials

Posted on November 30, 2018 by Chris Grieves

Metapopulation Microcosm Plates (MMP) are devices which resemble 96-well microtiter plates in size and shape, but with corridors connecting the wells in any configuration desired. They can be used to culture microbial metapopulations or metacommunities with up to 96 habitat patches.

In these two video tutorials, Helen Kurkjian explains how you can assemble, fill and clean MMPs in your lab.

Continue reading →

Spatial Cross-Validation of Species Distribution Models in R: Introducing the blockCV Package

Posted on November 29, 2018 by Chris Grieves

Post provided by Roozbeh Valavi

این پست به فارسی موجود است

Modelling species distributions involves relating a set of species occurrences to relevant environmental variables. An important step in this process is assessing how good your model is at figuring out where your target species is. We generally do this by evaluating the predictions made for a set of locations that aren’t included in the model fitting process (the ‘testing points’).

Random splitting of the species occurrence data into training and testing points

The normal, practical advice people give about this suggests that, for reliable validation, the testing points should be independent of the points used to train the model. But, truly independent data are often not available. Instead, modellers usually split their data into a training set (for model fitting) and a testing set (for model validation), and this can be done to produce multiple splits (e.g. for cross-validation). The splitting is typically done randomly. So testing points sometimes end up located close to training points. You can see this in the figure to the right: the testing points are in red and training points are in blue. But, could this cause any problem? Continue reading →

اعتبارسنجی متقاطع مکانی در مدلسازی توزیع گونه‌‌ها

Posted on November 29, 2018 by Chris Grieves

نویسنده: روزبه وَلَوی

This post is available in English

مدلسازی توزیع گونه‌ها به تخمین و برآورد ارتباط بین مجموعه‌ای از نقاط حضور گونه با متغیرهای زیست‌محیطی مرتبط می پردازد. یکی از مراحل اساسی این فرایند، ارزیابی قدرت مدل برای پیشبینی مکان‌هایی است که احتمال حضورگونه در آنجا وجود دارد. این کار اغلب با ارزیابی پیشبینی انجام شده در مجموعه‌ای ازنقاط که در فرآیند مدلسازی مورد استفاده قرار نگرفته اند (نقاط آزمایشی) صورت می‌گیرد.

تقسیم تصادفی داده‌های حضور گونه به نقاط آزمایشی و آموزشی

مطالعات پیشین بر این نکته تاکید دارند که به منظور ارزیابی معتبر، نقاط آزمایشی باید مستقل از نقاط آموزشی باشند، این درحالیست که داده مستقل واقعی به ندرت در دسترس می باشد. به همین دلیل، در فرایند مدلسازی معمولا داده‌های موجود را به دو قسمت داده‌های آموزشی (برای کالیبره کردن مدل) و داده های آزمایشی (برای ارزیابی دقت مدل) تقسیم می‌کنند، این استراتژی می‌تواند چند قسمتی هم باشد (برای مثال اعتبارسنجی متقاطع یا cross-validation). از آنجاییکه این تقسیم بندی معمولا بصورت تصادفی انجام می‌شود، بنابراین گاهی اوقات نقاط آزمایشی در فواصل نزدیک به نقاط آموزشی قرار می‌گیرند. شکل زیر این مساله را به خوبی نشان می دهد که در آن نقاط آزمایشی به رنگ قرمز و نقاط آموزشی آبی هستند. اما آیا این مساله می‌تواند مشکلی ایجاد کند؟ Continue reading →

Monitoring Ecosystems through Sound: The Present and Future of Passive Acoustics

Posted on November 15, 2018 by Chris Grieves

Post provided by Ella Browning and Rory Gibb

AudioMoth low-cost, open-source acoustic sensor ©openacousticdevices.info

As human impacts on the world accelerate, so does the need for tools to monitor the effects we have on species and ecosystems. Alongside technologies like camera traps and satellite remote sensing, passive acoustic monitoring (PAM) has emerged as an increasingly valuable and flexible tool in ecology. The idea behind PAM is straightforward: autonomous acoustic sensors are placed in the field to collect audio recordings. The wildlife sounds within those recordings are then used to calculate important ecological metrics – such as species occupancy and relative abundance, behaviour and phenology, or community richness and diversity.

The Pros and Cons of Passive Acoustic Monitoring

Using sound to monitor ecosystems, rather than traditional survey methods or visual media, has many advantages. For example, it’s much easier to survey vocalising animals that are nocturnal, underwater or otherwise difficult to see. Also, because acoustic sensors capture the entire soundscape, it’s possible to calculate acoustic biodiversity metrics that aim to describe the entire vocalising animal community, as well as abiotic elements in the environment.

The use of PAM in ecology has been steadily growing for a couple of decades, mainly in bat and cetacean studies. But with sensor costs dropping and audio processing tools improving, there’s currently a massive growth in interest in applying acoustic methods to large-scale or long-term monitoring projects. As very low-cost sensors such as AudioMoth start to emerge, it’s becoming easier to deploy large numbers of sensors in the field and start collecting data. Continue reading →

In Conservation Planning, Some Data are More Important Than Others

Posted on November 9, 2018 by Chris Grieves

Provided by Heini Kujala and José Lahoz-Monfort

Esta entrada de blog también está disponible en español

Spatial Conservation Planning and the Quest for Perfect Data

Conservation planners and managers often need to make decisions with imperfect information. When deciding what action to take or how to divide resources between candidate locations, we rarely have all the information we’d like on what species are present at a site or which areas are most critical for supporting their population viability. A large volume of ecological research focuses on answering these very questions.

To make conservation decisions, we need other types of data as well. These include information on things like the cost of carrying out a given conservation action, current condition of sites, the distribution and intensity of threats in a region, and much more. Many conservation problems are spatial, meaning that we often need to decide between multiple candidate locations and that there are spatial dependencies between sites that need to be accounted for. All these different pieces of information are needed to make cost-efficient and effective conservation decisions.

Ecologists and conservation biologists are usually concerned about the completeness and accuracy of the ecological data used to make these decisions (understandably). But less effort has been spent in researching and verifying the accuracy of the types of data mentioned above. At the same time, we have relatively poor understanding of how data gaps influence solutions optimised across multiple species and locations, and the relative importance of gaps in different types of data. This is what we set out to find in ‘Not all data are equal: Influence of data type and amount in spatial conservation prioritisation’. Continue reading →

En la planificación de la conservación, algunos datos son más importantes que otros

Posted on November 9, 2018 by Chris Grieves

Por Heini Kujala y José Lahoz-Monfort

This blog post is also available in English

La planificación espacial de la conservación y la búsqueda de datos perfectos

Los planificadores y administradores de la conservación a menudo necesitan tomar decisiones con información imperfecta. Al decidir qué acción tomar o cómo dividir recursos entre diferentes localizaciones, rara vez tenemos toda la información que nos gustaría sobre qué especies están presentes en un lugar o qué áreas son las más críticas para respaldar su viabilidad poblacional. Un gran volumen de investigación ecológica se focaliza en responder a estas preguntas.

Para tomar decisiones de conservación, también necesitamos otros tipos de datos, incluyendo, entre otros, información sobre el costo de llevar a cabo una acción de conservación determinada, la condición actual de los diferentes sitios, y la distribución e intensidad de las amenazas en una región. Muchos problemas de conservación son espaciales, es decir que a menudo tenemos que decidir entre varias ubicaciones candidatas, con dependencias espaciales entre ellas. Todas estas diferentes piezas de información son necesarias para tomar decisiones de conservación rentables y efectivas.

Los ecólogos y los biólogos de la conservación suelen estar preocupados por la integridad y exactitud de los datos ecológicos utilizados para tomar estas decisiones (comprensiblemente). Pero se ha dedicado menos esfuerzo a investigar y verificar la exactitud de los otros tipos de datos mencionados anteriormente. Además, tenemos una comprensión relativamente pobre de cómo las lagunas en los datos influyen en las soluciones optimizadas en múltiples especies y ubicaciones, y la importancia relativa de las lagunas en los diferentes tipos de datos. Es esto precisamente lo que nos propusimos investigar en el artículo ‘Not all data are equal: Influence of data type and amount in spatial conservation prioritisation’. Continue reading →

New Research Shows Pretend Porpoise Sounds are Helping Conservation Efforts

Posted on October 31, 2018 by Chris Grieves

Below is a press release about the Methods in Ecology and Evolution article ‘Estimating effective detection area of static passive acoustic data loggers from playback experiments with cetacean vocalisations‘ taken from Swansea University.

Harbour porpoise under the surface – I. Birks, SeaWatchFoundation

An examination into the detection of harbour porpoises is helping to give new understanding of effective monitoring of species under threat from anthropogenic activities such as fisheries bycatch and coastal pollution.

In a first study of its kind, Dr Hanna Nuuttila, currently at Swansea University’s College of Science – together with scientists from the German Oceanographic Museum, the University of St Andrews and Bangor University – revealed how playing back porpoise sounds to an acoustic logger can be used to assess the detection area of the device, a metric typically required for effective monitoring and conservation of protected species.

Continue reading →

How do You Know that the Top Dog is Really the Top Dog? Using Elo-Ratings and Bayesian Inference to Determine Rankings in Animal Groups

Posted on October 29, 2018 by Chris Grieves

Post provided by Julia Fischer

A female chacma baboon (rear) signals her submission to another female by raising her tail. ©Julia Fischer.

Anyone who studies social animals in the wild (or human groups, for that matter), will soon find that some individuals threaten or attack others frequently, while others try to get out of the way or signal their submission in response to aggression. Observers tally the outcome of such aggressive interactions between any given two individuals (or ‘dyads’) and try to deduce the rank hierarchy from such winner-loser matrices. One drawback of this approach is that all temporal information is lost.

Imagine Royal, a baboon, dominating over Power, another baboon, 20 times, and Power dominating over Royal 20 times as well. If we just look at these data, we might think that they have the same fighting ability and similar ranks. But, if we know that Royal beat Power the first 20 of the interactions, then Power beat Royal in all further interactions, we’d come to a totally different conclusion. We’d infer that Power had toppled Royal and a rank change had taken place.

How do Rank Hierarchies Change Over Time?

One prominent method that takes the temporal dynamics of winner-loser interactions into account was originally developed to calculate the relative skill level of chess players. This method was introduced by Arpad Elo and is hence known as Elo-Rating. Elo-Rating has also been applied to rate the relative skills in a variety of competitive fields, including Major League Baseball, video games, and Scrabble. Continue reading →

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