Oxford Research Sheds Light on the Secret Life of Badgers

Below is a press release about the Methods paper ‘An active-radio-frequency-identification system capable of identifying co-locations and social-structure: Validation with a wild free-ranging animal‘ taken from the University of Oxford.

© Peter Trimming

Detecting the movements and interactions of elusive, nocturnal wildlife is a perpetual challenge for wildlife biologists. But, with security tracking technology, more commonly used to protect museum artwork, new Oxford University research has revealed fresh insights into the social behaviour of badgers, with implications for disease transmission.

Previous studies have assumed that badgers are territorial and, at times, anti-social, living in tight-knit and exclusive family groups in dens termed ‘setts’. This led to the perception that badgers actively defend territorial borders and consequently rarely travel beyond their social-group boundaries.

This picture of the badger social system is so widely accepted that some badger culling and vaccination programmes rely on it – considering badger society as being divided up into discrete units, with badgers rarely venturing beyond their exclusive social-groups. But, the findings, newly published in Methods in Ecology and Evolution, have revealed that badgers travel more frequently beyond these notional boundaries than first thought, and appear to at least tolerate their neighbours. Continue reading

Britain’s Smallest Bird Affected by Cold Winters: New Analysis Methods Relate Wildlife Abundance to Weather

Below is a press release about the Methods paper ‘Attributing changes in the distribution of species abundance to weather variables using the example of British breeding birds‘ taken from the University of St Andrews.

©CJ Hughson

The goldcrest is being hit hard by cold winters. ©CJ Hughson

Britain’s smallest bird species, the goldcrest, is being hit hard by cold winters, new analysis methods developed by researchers at the University of St Andrews have revealed.

The data analysis techniques, published today in Methods in Ecology and Evolution, take a longer term view over multiple locations and for a period of several years, compared to previous studies.

They showed that the cold temperatures strongly affected breeding numbers of the goldcrest, while in contrast, the song thrush was not affected by the cold, but benefited from wet and mild summers. Continue reading

Fast-Moving Biodiversity Assessment: Are We Already in the Future?

Post provided by Carola Gómez-Rodríguez & Alfried P. Vogler

Time flies… in the blink of an eye! And even more so in science. The molecular lab work we were used to two decades ago seems like ancient history to today’s PhD students. The speed of change in sequencing technology is so overwhelming that imagination usually fails to foresee how our daily work will be in 10 years’ time. But in the field of biodiversity assessment, we have very good clues. Next Generation Sequencing is quickly becoming our workhorse for ambitious projects of species and genetic inventories.

One by One Approach to Studying Biodiversity

For decades, most initiatives measured biodiversity in the same way: collect a sample of many individuals in the field, sort the specimens, identify them to a Linnaean species one at a time (if there was a good taxonomist in the group which, unfortunately, it is kind of lucky these days!), and count them. Or, if identification was based on molecular data, the specimen was subject to DNA extraction, to sequence one (or several) short DNA markers. This involved countless hours of work that could be saved if, instead of inventorying biodiversity specimen-by-specimen, we followed a sample-by-sample approach. To do this now, we just have to make a “biodiversity soup”.

Biodiversity assessment based on morphological identification and/or Sanger sequencing (“The one-by-one approach”)

Biodiversity assessment based on morphological identification and/or Sanger sequencing (“The one-by-one approach”)

Continue reading

Estimating the Size of Animal Populations from Camera Trap Surveys

Below is a press release about the Methods paper ‘Distance sampling with camera traps‘ taken from the Max Planck Society.

A Maxwell's duiker photographed using a camera trap. Marie-Lyne Després-Einspenner

A Maxwell’s duiker photographed using a camera trap. ©Marie-Lyne Després-Einspenner

Camera traps are a useful means for researchers to observe the behaviour of animal populations in the wild or to assess biodiversity levels of remote locations like the tropical rain forest. Researchers from the University of St Andrews, the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) and the German Centre for Integrative Biodiversity Research (iDiv) recently extended distance sampling analytical methods to accommodate data from camera traps. This new development allows abundances of multiple species to be estimated from camera trapping data collected over relatively short time intervals – information critical to effective wildlife management and conservation.

Remote motion-sensitive photography, or camera trapping, is revolutionising surveys of wild animal populations. Camera traps are an efficient means of detecting rare species, conducting species inventories and biodiversity assessments, estimating site occupancy, and observing behaviour. If individual animals can be identified from the images obtained, camera trapping data can also be used to estimate animal density and population size – information critical to effective wildlife management and conservation. Continue reading

Digitizing Historical Land-use Maps with HistMapR

Habitat destruction and degradation represent serious threats to biodiversity, and quantification of land-use change over time is important for understanding the consequences of these changes to organisms and ecosystem service provision.

Historical land-use maps are important for documenting how habitat cover has changed over time, but digitizing these maps is a time consuming process. HistMapR is an R package designed to speed up the digitization process, and in this video we take an example map to show you how the method works.

Digitization is fast, and agreement with manually digitized maps of around 80–90% meets common targets for image classification. We hope that the ability to quickly classify large areas of historical land use will promote the inclusion of land-use change into analyses of biodiversity, species distributions and ecosystem services.

This video is based on the Applications article ‘HistMapR: Rapid digitization of historical land-use maps in R‘ by Auffret et al. This article is freely available to anyone (no subscription required).

The package is hosted on GitHub and example scripts can be downloaded from Figshare.

When Measuring Biodiversity, Do Individuals Matter?

Post provided by Samuel RP-J Ross

Close up of a black-capped babbler (Pellorneum capistratum), one of the species included in our study.

Close up of a black-capped babbler (Pellorneum capistratum), one of the species in our study.

Our newly-developed method simulates intraspecific trait variation when measuring biodiversity. This gives us an understanding of how individual variation affects ecosystem processes and functioning. We were able to show that accounting for within-species variation when measuring functional diversity can reveal details about ecological communities which would otherwise remain unseen. Namely, we found a negative impact of selective-logging on birds in Borneo when accounting for intraspecific variation which we could not detect when ignoring intraspecific variation.

Why Biodiversity Matters

Biodiversity is important for many reasons. One of the main reasons is its contribution to the range of goods and services provided by ecosystems (i.e. ecosystem services) that we can take advantage of, such as natural food resources or climatic regulation. It’s generally believed that biodiversity contributes to these services by increasing and maintaining ‘ecosystem functioning’ – often defined as the rate at which ecosystems are turning input energy (e.g. sunlight) into outputs (e.g. plant biomass). Continue reading

Capturing the Contribution of Rare and Common Species to Turnover: A Multi-Site Version of Generalised Dissimilarity Modelling

Post provided by Guillaume Latombe and Melodie A. McGeoch

Understanding how biodiversity is distributed and its relationship with the environment is crucial for conservation assessment. It also helps us to predict impacts of environmental changes and design appropriate management plans. Biodiversity across a network of local sites is typically described using three components:

  1. alpha (α) diversity, the average number of species in each specific site of the study area
  2. beta (β) diversity, the difference in species composition between sites
  3. gamma (γ) diversity, the total number of species in the study area.
Two tawny frogmouths, a species native to Australia. ©Marie Henriksen.

Two tawny frogmouths, a species native to Australia. ©Marie Henriksen.

Despite the many insights provided by the combination of alpha, beta and gamma diversity, the ability to describe species turnover has been limited by the fact that they do not consider more than two sites at a time. For more than two sites, the average beta diversity is typically used (multi-site measures have also been developed, but suffer shortcomings, including difficulties of interpretation). This makes it difficult for researchers to determine the likely environmental drivers of species turnover.

We have developed a new method that combines two pre-existing advances, zeta diversity and generalised dissimilarity modelling (both explained below). Our method allows the differences in the contributions of rare versus common species to be modelled to better understand what drives biodiversity responses to environmental gradients. Continue reading

Carson’s Call: An Inspiration for Ecologists Working in a Post-Truth World

Post provided by Will Pearse

Rachel Carson (1940) Fish & Wildlife Service employee photo.

Rachel Carson (1940) Fish & Wildlife Service employee photo.

I can’t think of a more inspirational and influential ecologist than Rachel Carson. Nearly fifty years ago she released a book called Silent Spring, which argued that pesticides such as DDT were cascading up through food chains causing the death or sterilisation of birds and other animals. The publication of her book provoked public debate, likely in part because it was serialised in The New Yorker, and led to a paradigm shift in US and (arguably) global pest control policy.

With the full support of the scientific community to verify her facts and arguments, she was able to defeat the chemical industry’s backlash and galvanise public opinion in her favour. The 2005 Stockholm Convention, in which DDT was banned from agricultural use, would likely have never happened if it were not for her work.

“In a post-truth world where trust in the scientific process is being eroded almost daily, Rachel Carson is a perfect example of how we can speak out and be heard while still being scientists.”

Continue reading

Biomonitoring Pollution in Wetlands: A New Method for More Reliable Interpretation of Chemical Data

Post provided by Mark Gillingham and Fabrizio Borghesi

Wetlands tend to accumulate considerable anthropogenic pollution.

Wetlands tend to accumulate considerable anthropogenic pollution.

All living organisms are dependent on trace elements (TEs), including metals, that are acquired in very small quantities through their environment or diet. Most TEs are essential for growth, development and physiology of the organism, but excessive intake can be detrimental for animals and plants.  Some TEs – especially heavy metals such as mercury, cadmium, lead and others – are generally toxic though. This toxicity occurs because species’ natural mechanisms fail to excrete excess TEs quickly enough for their metabolism to cope. TEs are present in the environment at different concentrations, either through natural processes or anthropogenic processes (i.e. pollution).

Since the industrial revolution, pollution from human activities has dramatically increased the concentrations of TEs in the natural environment. TEs from pollution tend to persist for a long time on the top layer of soils and sediments, because they do not undergo microbial degradation. As a consequence they tend to enter the food web quicker than the same elements of natural origin.

Some natural environments are more vulnerable to toxic effects of TEs. For instance, wetlands are geochemical endpoints of large river systems that often flow near or through cities, roads, factories, industries, cultivated lands, and/or mines, so they tend to accumulate considerable anthropogenic pollution. Vulnerable habitats like wetlands need to be closely monitored in order to assess the environmental health of these ecosystems. For this kind of monitoring we need reliable methods to measure TEs exposure, intake and bioaccumulation. Continue reading

Lichens and the “health” of ecosystems: we are closer to a global ecological indicator

Below is a press release about the Methods paper ‘Tracking global change using lichen diversity: towards a global-scale ecological indicator‘ taken from the University of Lisbon.

Candelaria pacifica. © Paula Matos

Candelaria pacifica. © Paula Matos

For the first time, it is possible to integrate at the global scale the results obtained with the most widely used methods to evaluate the “health” of ecosystems using lichens. This is the result of a study now published in the journal Methods in Ecology and Evolution, and represents a fundamental step for this indicator to be considered at the global scale and included in the list of indicators of the United Nations.

Lichens have long been successfully used by scientists as ecological indicators – a kind of environment health thermometer. These complex organisms – the yellow or green taints we often see on the surface of tree trunks – are very sensitive to pollution and changes in temperature and humidity. Evaluating how many lichens, of what kind, and their abundance in a certain ecosystem allows scientists to understand the impact that problems like climate change or pollution have on those ecosystems.  Continue reading