Kristin Scharnweber

So much fun to look at perch living in more salty waters and to link feeding specialization to a fitness proxy! This work was in collaboration with the fantastic Anna Gårdmark from the Institute of Coastal Research, Öregrund (SLU).

My paper on minnow divergence “Morphological and trophic divergence of lake and stream minnows (Phoxinus phoxinus )” has been published in Ecology and Evolution.

I enjoy working in collaborations and usually, my papers have many coauthors. With this one it was different and I wrote it as a single author. However, this study would not have been possible without the help of many different assistants and interns. Especially Leonie Haferkemper and Holger Villwock were an amazing help (and a lot of fun!) during field- and labwork!

It has been a long ride but now Fernando´s first PhD chapter is published in Oecologia! YES!

Fernando successfully defended his PhD thesis entitled “Bottom-up and top-down control of heterogeneous food webs” on April 3rd. With about 10 participants in the same room and 63 (!) that joined via zoom, this has set a new record for the number of followers for a defense in Limno history! He had a great discussion with his opponent Blake Matthews (eawag) and the committee Monica Winder (Stockholm University), Pär Byström (Umeå University), and Christer Brönmark (Lund University). I am very proud of Fernando’s achievements!

Another manuscript emerged from the KAWater mesocosms and turned into a Freshwater Biology article: “The emergence of fatty acids – Aquatic insects as vectors along a productivity gradient”

Congratulations to Robyn and Erik who successfully defended their Master’s theses!

Robyn´s thesis has the title “The effect of different browning agents on the fitness and survival of Daphnia magna”. Robyn picked up on the findings of decreased zooplankton abundances of the first KAWater mesocosm experiments in 2016 in treatments with HuminFeed and conducted standardized OECD toxicity tests on lab cultures of Daphnia. Her results show a clear reduction in offspring numbers when Daphnia is cultured in HuminFeed, highlighting that this browning agents should only be used with greatest caution in future browning-related experiments.

For his thesis “Effects of productivity and predation on zooplankton and emerging chironomids in a mesocosm experiment”, Erik has collected zooplankton and emerging Chironomidae from the mesocosm experiment conducted in summer 2017. Therefore, he did an excellent handcraft-job by building the emergence traps that we also could further use in the next season. In his thesis, he found interesting interactions between bottom-up and top-down effects where nutrients can mitigate the effects of predation pressure.

Another chapter of Marias’ thesis was published. Ecology and Evolution “Asymmetrical habitat coupling of an aquatic predator—The importance of individual specialization”.

The first mesocosm paper is out! Congrats Anna for your work and endurance during the review process!

We have ended the KAWater mesocosm experiments at Lake Erken! We had three exciting years of sampling, trying things and sometimes fail. Now we have accumulated a lot of samples, some of them processed and some of them still waiting to be analyzed. I am looking forward for the interesting things we will learn from these experiments, but we have finalized one big step and that is the actual sampling. Many, many hands have helped during these campaigns. Thank you so much to the great KAWater team! Without your work, sweat, patience and endurance, this project would not be possible!

For one week, me and my fabulous assistants Leonie and Holger went to Jämtland in Northern Sweden to catch minnows (Phoxinus phoxinus) in beautiful Lake Ånnsjön and its tributaries to look at divergence patterns between the fishes inhabiting the lake vs. stream habitats. It has been an exhausting but very successful week in an amazing landscape.