How to preserve subterranean biodiversity

Our international collaborative team in the Biodiversa funded project DarCo has published a perspective paper in npj biodiversity. Subterranean ecosystems, consisting of terrestrial, semi-aquatic, and aquatic components, face increasing threats from human activities, and existing surface-protected areas are insufficient to safeguard their biodiversity. Establishing protected areas for subterranean ecosystems is hindered by technical challenges in mapping three-dimensional systems, the rarity and endemism of subterranean organisms, and the need for collaboration among multiple stakeholders with competing interests. Despite uncertainties, our paper emphasizes the timely and critical assessment of general criteria for subterranean biodiversity protection, advocating for their implementation based on precautionary principles and proposing solutions to enhance the coverage of subterranean ecosystems within European protected areas.

Groundwater is a hidden keystone ecosystem

In an international collaboration published in Global Change Biology, we investigated the importance of groundwater as a key global ecosystem. Groundwater plays a central role in the global water cycle, harbors a unique biodiversity and provides important ecosystem services such as clean drinking water. However, it is under increasing pressure and is often neglected in nature conservation. Our assessments show that groundwater interacts with more than half of the land surface. It is therefore essential to recognize its interconnected nature and pursue holistic approaches to groundwater protection. We propose eight concrete steps for a scientific and political agenda to protect groundwater and combat the loss of its biodiversity.

The Conversation published an article on the publication:

Taxonomic work on groundwater organisms

The latest two publications from our work on groundwater treat taxonomic questions on Niphargus and Haplotaxis. In a first study published in Zoologischer Anzeiger, we used molecular methods to review the taxonomic status of the Niphargus ruffoi clade, including the species N. ruffoi and Niphargus arolaensis, across the Alpine arc. In another study published in Zoosymposia, we questioned the supposedly sub-cosmopolitan species status of Haplotaxis gordioides, with our results suggesting that the species is a complex of at least 6 cryptic species in Switzerland.

Hints on how to keep Gammarus fossarum

Flow through system at Eawag, used to keep Gammarus fossarum.

Being a field biologist by training, I always wanted to study my beloved amphipods under laboratory conditions. Turns out it is not as straightforward. Our recent publication in Science of The Total Environment highlights some of the things we learned over the last few years. While some amphipod species such as Hyalella azteca are easy to breed in captivity, the freshwater genus Gammarus from Central Europe is notoriously hard to keep and maintain in the lab. Hence, most experiments rely on wild-caught animals. From an scientific point of view, having lab-bred individuals available is the preferred option. To improve survival and reproduction in lab cultures of Gammarus fossarum, we caught thousands of G. fossarum and ran several experiments in our laboratory facilities, tweaking around with food supply, day-length, water temperature, cage size etc. We supplemented the diet of G. fossarum with protein-rich food and provided additional shelter. Both these measures increased survival rate of laboratory-based populations significantly, especially the feed enrichment. We also manipulated the day length (fixed vs. variable). We did not observe a significant effect of day length on the abundance and reproductive activity of G. fossarum. Apart from these main findings, we provide several detailed husbandry protocols in the paper ( They are intended as starting point for future experiments in environmental sciences and ecotoxicology that rely on lab-bred G. fossarum. I want to thank everyone involved in improving our lab cultures of G. fossarum, especially Sarah Bollina, Eva Cereghetti, Morris Galli, Samuel Hürlemann, Silvana Kaeser, Chelsea Little, Manja Schleich and I want to acknowledge financial support by Eawag, University of Zurich, and BAFU.