Examining Sediment Quality and its Influence on Brown Trout Egg Development with an Innovative Sediment Trap

Brown Trout Yolk Sac Larva in water with high concentration of fine sediment particles

What is known as the aftermath of intensified flood events has similar impact on life below water. This increases the entry of fine sediment particles into streams as well as periodically dried soil due to a higher erosion and sediment mobility, combined with extensive agricultural land use along the water edges. This endangers key-stone species especially the brown trout salmo trutta fario due to clogged gravel-gap-systems they need to spawn. Within this study, a sediment trap was developed as a method for long-term sampling during spawning time and tested in five Bavarian streams. Furthermore, the impact of these sediment compositions on the development of brown trout eggs was determined to improve the success of in-situ-floating incubators to restore their populations.

This is how I came up with the idea for this project:

Talking to an angler of our neighborhood, I grew aware of the decreasing brown trout populations in our rivers. I wanted to help, so I set up a brown-trout-fry-in-situ-incubation. Cleaning the incubator, I met 30 liters of mud. That was when the idea of a sediment trap was born.

Raising Awareness for Life under Water

As a Girl Scout, passing that appreciation for life under water on to our younger ones, is very dear to me. Because this is what creates that sense of responsibility. That you can make a change if only you care enough. This is why I invited our younger scouts on the deployment of the hatched larvae at the Friedberger Ach. Also, there was one of the fishermen responsible with us, being asked a lot of questions by the scouts. Furthermore, I managed to include the youth association of the fishery club at the Prien into the sampling. Currently, I am working on organizing workshops in this regard at the Konstanzer Ach. At my voluntary ecological year at the Centre for Aquaculture Research of the Alfred-Wegener-Institute, I also included workshops on the topic for visiting students.

Future Research

I am more than curious about the long-term results of the cooperation with the „gewässerkundliche Dienst“, the scientific water service of the Konstanzer Ach in 2025.