It’s the 22nd of September and that means it’s this year’s UN World Rivers Day! In over 60 countries around the globe events are going on today to bring attention to the many values of our waterways. And we, the Aquatic Ecology Special Interest Group of the BES, are joining in with the celebrations! We’re highlighting recent methodological advancements that will help us to manage and conserve our rivers in the future. So let’s get started…
Multiple Stressors and Molecular Tools
Today, human activities across the world are impacting rivers to varying degrees. As scientists, we frequently see the interaction of multiple different stressors such as flow regulations, pollution or climate change affecting our rivers. The combined impact of stressors like these may be worse than any of their individual impacts. To understand and manage the effect of them, we need cost-effective and reliable analytical tools that can capture site-specific and ecosystem-wide effects.
Recent methodological advances that will help us to achieve these goals often rely on the application of new or improved molecular tools. Emerging techniques include environmental DNA (eDNA) based applications to monitor endangered and invasive species as well as stable isotope ecology, which provides us with new insights into animal diets and energy flows through aquatic food webs. We’d like to take the opportunity to introduce some of the novel developments in both of these exciting fields. Continue reading →
With the extra long issue, comes more free articles. There are ELEVEN papers in our August issue that are free to access for absolutely anyone. You can find out about the four Practical Tools papers and seven Applications articles below.
It’s estimated that a person sheds between 30,000 to 40,000 skin cells per day. These cells and their associated DNA leave genetic traces of ourselves in showers, dust — pretty much everywhere we go.
Other organisms shed cells, too, leaving traces throughout their habitats. This leftover genetic material is known as environmental DNA, or eDNA. Research using eDNA began about a decade ago, but was largely limited to a small cadre of biologists who were also experts in computers and big data. However, a new tool from UCLA could be about to make the field accessible and useful to many more scientists.
A team of UCLA researchers recently launched the Anacapa Toolkit — open-source software that makes eDNA research easier, allowing researchers to detect a broad range of species quickly and producing sortable results that are simple to understand. Continue reading →
Researchers at Washington State University and Smith-Root recently invented an environmental DNA (eDNA) filter housing that automatically preserves captured eDNA by desiccation. This eliminates the need for filter handling in the field and/or liquid DNA preservatives. The new material is also biodegradable, helping to reduce long-lasting plastic waste associated with eDNA sampling.
This video explains their new innovation in the field of eDNA sampling technology:
A new self-preserving filter housing automatically preserves eDNA, while reducing the risk of contamination, and creating less plastic waste.
Researcher collecting an eDNA sample using the self-preserving filter housing.
In 2015 the inventor of the Keurig disposable coffee cartridge (K-Cups) told reporters that sometimes he regrets ever inventing the technology. The single-use design simply produces too much non-recyclable trash. Well, that very same problem is what ultimately led to the creation of a self-preserving filter for environmental DNA (eDNA); a recently reported Practical Tool in Methods in Ecology and Evolution.
eDNA scientists rely on single-use sampling equipment because eDNA surveys are highly sensitive to potential contamination. “We started out simply looking for biodegradable plastics that could be molded into a filter housing, with the objective of reducing plastic waste.” says Dr. Austen Thomas who led the team of researchers and engineers who invented the Smith-Root eDNA Sampler. “That’s when we realized that some of the biodegradable compounds function by being highly hydrophilic.” Continue reading →
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.
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.
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.
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.
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 →
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.
“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 →