Signals in flux: Investigating the seasonal turnover of the diel vertical migration-inducing kairomone 5α-cyprinol sulfate

5α-cyprinol sulfate (CPS) is a chemical signal released by cyprinid fish that plays a crucial role in predator-prey interactions by inducing diel vertical migration (DVM) in Daphnia, a key process shaping freshwater ecosystem dynamics. While CPS-mediated DVM has long been considered a stable and predictable response to predation risk, this study challenges previous assumptions by demonstrating that CPS undergoes rapid turnover in aquatic systems. We show that CPS exudation is tightly linked to fish feeding intensity, independent of fish size, while microbial degradation emerges as the dominant removal process, with degradation rates reaching up to 85.7% per day in lake water. Seasonal field data from a mesotrophic lake reveal that CPS concentrations range from 40 to 900 ng/L over a season, peaking in late summer, putatively indicating increased fish feeding and shifts in prey availability. Using an integrated approach combining laboratory feeding trials, field sampling, and predictive m..., The dataset includes:

CPS degradation rates from microbial degradation assays
CPS exudation rates from fish feeding experiments
Seasonal in-situ CPS concentrations in lake water
Environmental parameters such as temperature and Secchi depth

Daphnia spp. abundances in lake samples
R scripts to analyse the datasets and plot figures 
, , # README: Signals in flux: Investigating the seasonal turnover of the DVM-inducing kairomone 5α-cyprinol sulfate

[https://doi.org/10.5061/dryad.4qrfj6qmz](https://doi.org/10.5061/dryad.4qrfj6qmz)

## Description of the data and file structure

This dataset was collected to investigate the seasonal turnover of the fish-derived kairomone 5α-cyprinol sulfate (CPS) in freshwater ecosystems.

To understand the environmental factors regulating CPS persistence and availability, we conducted a series of controlled laboratory experiments, field measurements, and predictive modeling. The experimental efforts included:

1. CPS Degradation Experiments – Investigating microbial breakdown of CPS in lake water.
2. CPS Exudation Experiments – Measuring how fish excrete CPS under different feeding conditions.
3. Seasonal CPS Monitoring – Tracking CPS concentrations in Reeser Meer Nord Erweiterung (RMNE) over a season.
4. Zooplankton Sampling – Assessing seasonal *Daphnia* abundance
5. Temperature-Depen..., ,