Department Aquatic Ecology

Aquatic Ecology

Eawag’s Department of Aquatic Ecology is currently home for eight research groups that cover the broad disciplines of ecology and evolution from the individual to the community and ecosystem level, utilizing a wide range of tools and techniques from microscopes to molecular genetics. Read more

News

Eawag agrees on cooperation with International Atomic Energy Agency

From left to right: Najat Mokhtar, IAEA Deputy Director General, Janet Hering, Eawag Director, and Benno Laggner, Ambassador, Permanent Representative and Governor of Switzerland to the IAEA and Head of the Swiss delegation to the IAEA General Conference. (Photo: Michael Berg)
September 27, 2022 –

Janet Hering, Director of the aquatic research institute Eawag, signed a cooperation agreement with the International Atomic Energy Agency (IAEA) on Monday 26 September 2022. The cooperation between Eawag and the IAEA should help...

Janet Hering, Director of the aquatic research institute Eawag, signed a cooperation agreement with the International Atomic Energy Agency (IAEA) on Monday 26 September 2022. The cooperation between Eawag and the IAEA should help to further advance groundwater research and support the sustainable utilisation of groundwater resources.
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Aquascope

Real-time underwater imaging for lake phytoplankton and zooplankton monitoring

Publications

Packman, A. I., Robinson, C. T., & Lamouroux, N. (2021). Hydraulic drivers of populations, communities and ecosystem processes. Journal of Ecohydraulics, 6(2), 91-94. doi:10.1080/24705357.2021.1951506, Institutional Repository
Nickel, J., Schell, T., Holtzem, T., Thielsch, A., Dennis, S. R., Schlick-Steiner, B. C., … Cordellier, M. (2021). Hybridization dynamics and extensive introgression in the Daphnia longispina species complex: new insights from a high-quality Daphnia galeata reference genome. Genome Biology and Evolution, 13(12), evab267 (23 pp.). doi:10.1093/gbe/evab267, Institutional Repository

Hybridization and introgression are recognized as an important source of variation that influence adaptive processes; both phenomena are frequent in the genus Daphnia, a keystone zooplankton taxon in freshwater ecosystems that comprises several species complexes. To investigate genome-wide consequences of introgression between species, we provide here the first high-quality genome assembly for a member of the Daphnia longispina species complex, Daphnia galeata. We further resequenced 49 whole genomes of three species of the complex and their interspecific hybrids both from genotypes sampled in the water column and from single resting eggs extracted from sediment cores. Populations from habitats with diverse ecological conditions offered an opportunity to study the dynamics of hybridization linked to ecological changes and revealed a high prevalence of hybrids. Using phylogenetic and population genomic approaches, we provide first insights into the intra- and interspecific genome-wide variability in this species complex and identify regions of high divergence. Finally, we assess the length of ancestry tracts in hybrids to characterize introgression patterns across the genome. Our analyses uncover a complex history of hybridization and introgression reflecting multiple generations of hybridization and backcrossing in the Daphnia longispina species complex. Overall, this study and the new resources presented here pave the way for a better understanding of ancient and contemporary gene flow in the species complex and facilitate future studies on resting egg banks accumulating in lake sediment.
Briscoe, A. G., Nichols, S., Hartikainen, H., Knipe, H., Foster, R., Green, A. J., … Bass, D. (2021). High-throughput sequencing of faeces provides evidence for dispersal of parasites and pathogens by migratory waterbirds. Molecular Ecology Resources, 22(4), 1303-1318. doi:10.1111/1755-0998.13548, Institutional Repository

Examination of faecal material has demonstrated how a broad range of organisms are distributed by bird movements. Such research has largely focused on dispersal of plant seeds by frugivores and of freshwater organisms by waterbirds. However, with few exceptions (e.g. avian influenza, Ebola virus), there is a dearth of evidence for transport of parasites and pathogens. High-throughput sequencing methods now provide a powerful means of addressing this knowledge gap by elucidating faecal contents in unprecedented detail. We collected faeces excreted by a range of migratory waterbirds in south-west Spain and pooled faecal DNA to create libraries reflective of feeding behavior. We created sets of libraries using high-throughput metagenomic and amplicon sequencing. For the latter we employed two sets of primers to broadly target the V4 region of the 18S rRNA gene (one set amplifying the region across all eukaryotes, the other excluding amplification of metazoans). Libraries revealed a wide diversity of eukaryotes, including parasites of the faecal producers themselves, parasites of food items, or those incidentally ingested. We also detected novel microbial eukaryotic taxa and found that parasite assemblage profiles were relatively distinct. Comparing the performance of the methods used supports their joint use for future studies of diversity and abundance. Because viable stages of many parasites are likely to be present in faeces, our results suggest significant levels of bird-mediated dispersal of parasites (both from avian and other hosts). Our methods revealed much hidden biodiversity, and allowed identification of the individuals who produced the faecal samples to species level, facilitating the study of interaction networks.

SNSF Fellowships Ambizione / Eccellenza / Prima

Information for potential candidates

Eco Seminars

12.10.​2022,
26.10.​2022,
11.00 am
Eawag Dübendorf, FC C24 or Zoom
Nonlinear dynamics for ecosystem forecasting and management
09.11.​2022,

Research Projects

Using freshwater isopods to understand how gut microbiome mediates host function in the face of environmental stress

The Asellus triangle: the host, the microbiome, and global change
Functional characterization of isopod-microbe symbiosis

Defensive Actinobacteria in freshwater- and terrestrial Isopods
The architecture of community structure, functional traits and trophic networks across blue-green ecosystems

Architecture of blue-green communities
New tools to monitor changes in ecosystem conditions and to quantify genetic changes of populations in (semi-)natural environments to predict how human mediated environmental change will influence stability and resilience of ecosystems.

Stability and the eco-evolutionary dynamics of ecosystems

More current Research Projects