One water bucket to find them all: Detecting fish, mammals, and birds from a single sample

Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study.

Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study

Collection of water samples for eDNA metabarcoding bioassessment.
Photo by Till-Hendrik Macher.

In times of exacerbating biodiversity loss, reliable data on species occurrence are essential, in order for prompt and adequate conservation actions to be initiated. This is especially true for freshwater ecosystems, which are particularly vulnerable and threatened by anthropogenic impacts. Their ecological status has already been highlighted as a top priority by multiple national and international directives, such as the European Water Framework Directive.

However, traditional monitoring methods, such as electrofishing, trapping methods, or observation-based assessments, which are the current status-quo in fish monitoring, are often time- and cost-consuming. As a result, over the last decade, scientists progressively agree that we need a more comprehensive and holistic method to assess freshwater biodiversity.

Meanwhile, recent studies have continuously been demonstrating that eDNA metabarcoding analyses, where DNA traces found in the water are used to identify what organisms live there, is an efficient method to capture aquatic biodiversity in a fast, reliable, non-invasive and relatively low-cost manner. In such metabarcoding studies, scientists sample, collect and sequence DNA, so that they can compare it with existing databases and identify the source organisms.

Furthermore, as eDNA metabarcoding assessments use samples from water, often streams, located at the lowest point, one such sample usually contains not only traces of specimens that come into direct contact with water, for example, by swimming or drinking, but also collects traces of terrestrial species indirectly via rainfalls, snowmelt, groundwaters etc. 

In standard fish eDNA metabarcoding assessments, these ‘bycatch data’ are typically left aside. Yet, from a viewpoint of a more holistic biodiversity monitoring, they hold immense potential to also detect the presence of terrestrial and semi-terrestrial species in the catchment.

In their new study, reported in the open-access scholarly journal Metabarcoding and MetagenomicsGerman researchers from the University of Duisburg-Essen and the German Environment Agency successfully detected an astonishing quantity of the local mammals and birds native to the Saxony-Anhalt state by collecting as much as 18 litres of water from across a two-kilometre stretch along the river Mulde.

After water filtration the eDNA filter is preserved in ethanol until further processing in the lab.
Photo by Till-Hendrik Macher.

In fact, it took only one day for the team, led by Till-Hendrik Macher, PhD student in the German Federal Environmental Agency-funded GeDNA project, to collect the samples. Using metabarcoding to analyse the DNA from the samples, the researchers identified as much as 50% of the fishes, 22% of the mammal species, and 7.4% of the breeding bird species in the region. 

However, the team also concluded that while it would normally take only 10 litres of water to assess the aquatic and semi-terrestrial fauna, terrestrial species required significantly more sampling.

Unlocking data from the increasingly available fish eDNA metabarcoding information enables synergies among terrestrial and aquatic biodiversity monitoring programs, adding further important information on species diversity in space and time. 

“We thus encourage to exploit fish eDNA metabarcoding biodiversity monitoring data to inform other conservation programs,”

says lead author Till-Hendrik Macher. 

“For that purpose, however, it is essential that eDNA data is jointly stored and accessible for different biodiversity monitoring and biodiversity assessment campaigns, either at state, federal, or international level,”

concludes Florian Leese, who coordinates the project.

Original source:

Macher T-H, Schütz R, Arle J, Beermann AJ, Koschorreck J, Leese F (2021) Beyond fish eDNA metabarcoding: Field replicates disproportionately improve the detection of stream associated vertebrate species. Metabarcoding and Metagenomics 5: e66557. https://doi.org/10.3897/mbmg.5.66557

New open-access journal Metabarcoding & Metagenomics joins the lines of publisher Pensoft

The new innovative academic journal makes use of the one-of-a-kind publishing platform ARPHA and its collaborative writing tool via the ARPHA-XML workflow

A new innovative open-access academic journal Metabarcoding and Metagenomics (MBMG) is launched to welcome novel papers from both basic and applied aspects.

Focusing on genetic approaches to study biodiversity across all ecosystems, MBMG covers a considerably large scope of research including environmental, microbial and applied metabarcoding and metagenomics (especially DNA-based bioassessment and -monitoring, quarantine, nature conservation, species invasions, eDNA surveillance), as well as associated topics, such as molecular ecology, DNA-based species delimitation and identification, and other emerging related fields. Submissions of bioinformatic approaches to MBMG (algorithms, software) are also encouraged.

Featuring novel article formats and data publishing workflows, MBMG is to reflect the rapid growth in the use of metabarcoding and metagenomics in life and environmental sciences.

Issued via ARPHA – the first ever publishing platform to support manuscripts all the way from authoring to peer review to publication and dissemination, designed by the academic publisher and technology provider Pensoft, the new journal is to host a wide range of outcomes from across the research cycle, including data, models, methods, workflows, software, perspectives, opinions, implementation strategies, as well as conventional research articles.

While the above-mentioned publication types are already available in other journals published on the ARPHA platform, such as Research Ideas and Outcomes (RIO)Biodiversity Data Journal and One Ecosystem, MBMG provides five extra domain-specific article types, namely: Emerging Technique, Applied Study, DNA Barcode Release, Primer Validation and Probe Validation.

The journal’s articles are to be available in three formats (PDF, XML, HTML) and full of semantic enhancements for better human- and machine-readability and discoverability. The XML-based workflow also ensures that content and data are available for extraction, indexing and re-use immediately after publication.

With Pensoft standing for transparent, reproducible and open science, the authors at MBMG are strongly encouraged to make all data publicly available either within the publication itself, or to link to external repositories. In their turn, the peer reviewers are also suggested to provide public access to their reviews and identities.

In time for the launch, MBMG has already gathered a team of experienced and renowned scientists from across the globe together on its editorial and advisory board.

“I am pleased to introduce the Metabarcoding and Metagenomics journal to the family of Pensoft,” says Prof. Lyubomir Penev, Founder and Managing Director at Pensoft. “With its exhaustive scope and advanced services and concept, I believe it fills fantastically a niche in our strong portfolio of mostly biodiversity- and ecology-themed journals.”

“Metabarcoding and metagenomics approaches are rapidly progressing and revolutionise research and its application alike,” Chief Editor Prof. Florian Leese states. “With the MBMG journal we provide an ideal platform to respond to this rapidly growing field, nucleate the emerging knowledge and stimulate further development.”

The first batch of research papers published in MBMG are now available on their new website.

“MBMG not only complements the range of journals in the field of molecular environmental life sciences, but also stands out as a novel outlet providing several unique features designed to help researchers to prepare for, and professionally deal with, the massive “deluge” of data,” reads the Editorial.

To celebrate the launch, MBMG starts with a tempting offer to potential authors: publishing will be completely free of charge during the beginning stages of the journal.

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