“Trends in Arthropods of Alpine Aquatic Ecosystems” is the first topical collection for the journal of the Swiss Entomological Society
The open-access, peer-reviewed scholarly journal Alpine Entomology, published by Pensoft on behalf of the Swiss Entomological Society, announced its very first topical collection of articles, which will be focusing on arthropods associated with aquatic ecosystems in mountainous regions.
The journal is currently inviting scientists, working on aquatic fauna from alpine habitats, to openly publish their research articles and short notices that provide evidence how arthropods’ biogeography, species communities, distribution, behaviour and morphology have changed in recent times.
Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study
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 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.
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
Biological invasions are widely recognised as one of the most significant components of global change. Far-reaching and fast-spreading, they often have harmful effects on biodiversity.
Therefore, acquiring knowledge of potentially invasive non-native species is crucial in current research. In particular, it is important that we enhance our understanding of the impact of such invasions.
To do so, Prof Sabrina Lo Brutto and Dr Davide Iaciofano, both working at the Taxonomy Laboratory of the University of Palermo, Italy, performed research on an invasive alien crustacean (Ptilohyale littoralis) known to have colonised the Atlantic European Coast. Their findings are published in the open access journal ZooKeys.
The studied species belongs to a group of small-sized crustaceans known as amphipods. These creatures range from 1 to 340 mm in length and feed on available organic matter, such as dead animals and plants. Being widely distributed across aquatic environments, amphipods have already been proven as excellent indicators of ecosystem health.
While notable for their adaptability and ecological plasticity, which secure their abundance in various habitats, these features also make amphipods especially dangerous when it comes to playing the role of invaders.
The problem was that, back in 1985, when the amphipod was first collected from European coasts, it was misidentified as a species new to science instead of an invader native to the North American Atlantic coast.
A closer look into misidentified specimens stored in museum collections revealed that the species has been successfully spreading along the European coastlines.
Moreover, it was predicted that the amphipod could soon reach the Mediterranean due to the high connectivity between the sea and the eastern Atlantic Ocean through the Straits of Gibraltar – a route already used by invasive marine fauna in the past.
In the event that the invader reaches the Mediterranean, it is highly likely for the crustacean to meet and compete with a closely related “sister species” endemic to the region. To make matters worse, the two amphipods are difficult to distinguish due to their appearance and behaviour both being extremely similar.
However, in their paper, the scientists have also provided additional information on how to distinguish the two amphipods – knowledge which could be essential for the management of the invader and its further spread.
The authors believe that their study demonstrates the importance of taxonomy – the study of organism classification – and the role of natural history collections and museums.
“Studying and monitoring biodiversity can acquire great importance in European aquatic ecosystems and coastal Mediterranean areas, where biodiversity is changing due to climate change and invasions of alien species,” Prof Lo Brutto says. “In this context, specific animal groups play a crucial role in detecting such changes and they, therefore, deserve more attention as fundamental tools in biodiversity monitoring.”
“Regrettably, the steadily diminishing pool of experts capable of accurately identifying species poses a serious threat in this field.”
Lo Brutto S, Iaciofano D (2018) A taxonomic revision helps to clarify differences between the Atlantic invasive Ptilohyale littoralis and the Mediterranean endemic Parhyale plumicornis(Crustacea: Amphipoda). ZooKeys, 754: 47-62. https://doi.org/10.3897/zookeys.754.22884