Hydrological connection links zooplankton communities and improves juvenile Chinook salmon growth in intertidal wetlands

Many once coupled habitats are now disconnected due to human infrastructure that prevents not only the transfer of organisms but also fundamental ecosystem processes. Here we investigate the importance of hydrologic connectivity between remnant floodplain and freshwater intertidal marsh habitats for zooplankton metacommunity dynamics and juvenile Chinook salmon growth in the Sacramento-San Joaquin Delta, California, U.S.A. Hydrological connection led to highly similar zooplankton communities between habitats. Further, we found that connected intertidal marsh habitats had approximately twice the total abundance of zooplankton of upstream floodplains and, in some cases, 15 times greater abundance than during disconnection. Gut content analysis demonstrated that salmon in our study utilized these abundant and high-value zooplankton food resources which likely contributed to elevated juvenile salmon growth rates in connected intertidal marsh habitats, where salmon had 25% greater growth rat..., , # Hydrological connection links zooplankton communities and improves juvenile Chinook salmon growth in intertidal wetlands

[https://doi.org/10.5061/dryad.c866t1gh1](https://doi.org/10.5061/dryad.c866t1gh1)

## Description of the data and file structure

This data was collected from 2019 -2020 in the California Delta; specifically in the Yolo Bypass, a restored intertidal marsh in Liberty Island, the Cosumnes River floodplain, and a intertidal marsh downstream of the Cosumnes River floodplains. Data includes water quality, zooplankton, and juvenile Chinook salmon growth data.

**wq.csv** - water quality data. NAs refer to when samples were not taken due to equipment malfunction, or in the case of time when collection times were not recorded. Site = location of collection, zooplankton at generic and family level, Temp_C = temperature degrees Celsius, EC = electrical conductivity uS/cm, SPC = specific electrical conductivity uS/cm, TDS = total dissolved solids mg/L, Sal=salinity PSU, DO_p...,