Tag Archives: eDNA

Using the Smith-Root ANDe System for Wildlife Conservation

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POST PROVIDED BY TRACIE SEIMON, PHD

The ANDe system can help researchers tell whether endangered species are present.

The ANDe system can help researchers tell whether endangered species are present.

In recent years, there have been a lot of studies on the use of environmental DNA (eDNA) for species detection and monitoring. This method takes advantage of the fact that organisms shed DNA into the environment in the form of urine, feces, or cells from tissue such as skin. As this DNA stays in the environment, we can use molecular techniques to search for traces of it. By doing this, we can determine if a species lives in a particular place.

At the Wildlife Conservation Society (WCS), we’re integrating and using the ANDe system in combination with ultra-portable qPCR (quantitative polymerase chain reaction) and DNA extraction technologies developed by Biomeme Inc. for eDNA capture and species detection of endangered turtles, and other aquatic organisms. This helps us to better monitor species within our global conservation programs. Continue reading →

Editor Recommendation: Assessing Strengths and Weaknesses of DNA Metabarcoding-Based Macroinvertebrate Identification for Routine Stream Monitoring

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Post provided by Andrew R. Mahon

The use of molecular methods for monitoring and surveillance of organisms in aquatic and marine systems has become more and more common. We’ve since expanded this technology this through using both captured whole organisms and collecting/filtering environmental DNA (eDNA).  These methods naturally migrated from single species, active surveillance methods towards using high throughput sequencing as a method of passive surveillance via metabarcoding.

In this virtual issue, the article “Assessing strengths and weaknesses of DNA metabarcoding-based macroinvertebrate identification for routine stream monitoring” by Vasco Elbrecht et al. provides an excellent overview to the field. It also helps to clarify the work being done to provide interested groups, including management agencies, with the best practices for utilising these new methods for monitoring and surveillance.  This work will help the field, particularly for those searching for rare species of organisms in aquatic systems.

I’d recommend this paper to all researchers and management groups interested in applying metabarcoding techniques to answer both experimental and applied questions. The design of this article will provide both experienced researchers and those new to the field with important information to further this rapidly expanding field.

To find out more about, read the full Methods in Ecology and Evolution article ‘Assessing strengths and weaknesses of DNA metabarcoding-based macroinvertebrate identification for routine stream monitoring’

 This article is part of ‘Practical Tools: A Field Methods Virtual Issue’. All articles in this Virtual Issue will be available for a limited time.

ANDe™: High‐Throughput eDNA Sampling in a Fully Integrated System

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Current eDNA sampling technologies consist mainly of do‐it‐yourself solutions. The lack of purpose‐built sampling equipment is limiting the efficiency and standardization of eDNA studies. So, Thomas et al. (a team of molecular ecologists and engineers) designed ANDe™.

In this video, the authors highlight the key features and benefits of ANDe™. This integrated system includes a backpack-portable pump that integrates sensor feedback, a pole extension with remote pump controller, custom‐made filter housings in single‐use packets for each sampling site and on-board sample storage. 

This video is based on the article ‘ANDe™: A fully integrated environmental DNA sampling system‘ by Thomas et al.

Uncertainties in Species Occurrence Data: How to deal with False Positives and False Negatives

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Post provided by Gurutzeta Guillera-Arroita

Species Surveys: New Opportunities and Ongoing Data Challenges

Technologies, such as drones, open new opportunities for wildlife monitoring ©J. Lahoz-Monfort, UMelb.

Technologies, such as drones, open new opportunities for wildlife monitoring ©J. Lahoz-Monfort, UMelb.

Monitoring is a fundamental step in the management of any species. The collection and careful analysis of species data allows us to make informed decisions about management priorities and to critically evaluate our actions. There are many aspects of a natural system that we can measure and, when it comes to monitoring the status of species, occurrence is a commonly used metric.

Ecologists have a long history of collecting species occurrence data from systematic surveys and our ability to gather species data is only going to grow! This is partly enabled by the fact that citizen science programs are starting to gain a prominent role in wildlife monitoring. There’s a growing recognition that well-managed citizen science surveys can produce useful data, while scaling up monitoring effort thanks to the increased human-power from large numbers of committed volunteers. Continue reading →

Refined DNA Tool Tracks Native and Invasive Fish

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Below is a press release about the Methods paper ‘Long-range PCR allows sequencing of mitochondrial genomes from environmental DNA‘ taken from the Cornell University.

©Nick Hobgood

Rather than conduct an aquatic roll call with nets to know which fish reside in a particular body of water, scientists can now use DNA fragments suspended in water to catalog invasive or native species.

The research from Cornell University, the University of Notre Dame and Hawaii Pacific University was published July 14 in Methods in Ecology and Evolution.

“We’ve sharpened the environmental DNA (eDNA) tool, so that if a river or a lake has threatened, endangered or invasive species, we can ascertain genetic detail of the species there,” said senior author David Lodge, the Francis J. DiSalvo Director of the Atkinson Center for a Sustainable Future at Cornell, and professor of ecology and evolutionary biology. “Using eDNA, scientists can better design management options for eradicating invasive species, or saving and restoring endangered species.” Continue reading →

Issue 7.11

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Issue 7.11 is now online!

The November issue of Methods is now online!

This month’s issue contains four Applications articles and two Open Access articles, all of which are freely available.

– moveHMM: This R package allows ecologists to process GPS tracking data into series of step lengths and turning angles, and to fit a hidden Markov model to these data, allowing, in particular, for the incorporation of environmental covariates.

– BORIS: An open-source and multiplatform standalone program that allows a user-specific coding environment to be set for a computer-based review of previously recorded videos or live observations. Being open to user-specific settings, the program allows a project-based ethogram to be defined that can then be shared with collaborators, or can be imported or modified.

– inbreedR: An R package that provides functions to measure variance in inbreeding – through the strength of correlation in heterozygosity across marker loci – based on microsatellite and SNP markers with associated P-values and confidence intervals. Within the framework of Heterozygosity–fitness correlation theory, inbreedR also estimates the impact of inbreeding on marker heterozygosity and fitness.

– Terrestrial Precipitation Analysis: This package is comprised of the Precipitation Trends (P-Trend), Precipitation Attributes (P-Att) and Precipitation Manipulation (P-Man) tools. Combined, these web tools allow researchers to easily calculate fundamental precipitation statistics for past, present and projected future precipitation regimes for any terrestrial location in the world.

Continue reading →

Issue 7.1

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Issue 7.1 is now online!

The January issue of Methods is now online!

As always, the first issue of the year is our sample issue. You can access all of the articles online free of charge. No subscription or membership is required!

We have two Open Access articles and two Applications papers in our January issue.

– Recognizing False Positives: Environmental DNA (eDNA) is increasingly used for surveillance and detection of species of interest in aquatic and soil samples. A significant risk associated with eDNA methods is potential false-positive results due to laboratory contamination. To minimize and quantify this risk, Chris Wilson et al. designed and validated a set of synthetic oligonucleotides for use as species-specific positive PCR controls for several high-profile aquatic invasive species.

– BiMat: An open-source MATLAB package for the study of the structure of bipartite ecological networks. BiMat enables both multiscale analysis of the structure of a bipartite ecological network – spanning global (i.e. entire network) to local (i.e. module-level) scales – and meta-analyses of many bipartite networks simultaneously. The authors have chosen to make this Applications article Open Access.

Gemma Murray et al. provide this month’s second Open Access article. In ‘The effect of genetic structure on molecular dating and tests for temporal signal‘ the authors use simulated data to investigate the performance of several tests of temporal signal, including some recently suggested modifications. The article shows that all of the standard tests of temporal signal are seriously misleading for data where temporal and genetic structures are confounded (i.e. where closely related sequences are more likely to have been sampled at similar times). This is not an artifact of genetic structure or tree shape per se, and can arise even when sequences have measurably evolved during the sampling period.

Our January issue also features articles on Monitoring, Population Ecology, Genetics, Evolution, Community Ecology, Diversity and more. Continue reading →