Predation alters community structure through multiple trophic cascades

Predation plays a crucial role in shaping community structure and can initiate trophic cascades that alter abundances across adjacent trophic levels. Intraspecific variation among predators could lead to varying levels of top-down control with implications for trophic cascade strength. In this experiment, we manipulated body size variation in populations of predatory mole salamanders (Ambystoma talpoideum) within mesocosms and monitored a suite of abiotic and biotic responses. Measurements of these responses are contained within this dataset. We predicted that predator populations with increased body size variation would have limited top-down control due to weaker interactions with greater numbers of prey species. Conversely, we predicted that populations with similarly sized predators would have strong control over fewer prey species, leading to trophic cascades. Salamander presence affected nearly every parameter measured, suppressing some populations (e.g., invertebrate predator..., , # Predation alters community structure through multiple trophic cascades

Dataset DOI: [10.5061/dryad.6q573n68k](10.5061/dryad.6q573n68k)

## Description of the data and file structure

This study examined how predator body size variation shapes aquatic community structure. We conducted mesocosm experiments with size-structured predatory mole salamanders and collected a suite of abiotic and biotic parameters, which are provided here. The primary dataset presents data collected at periodic sampling bouts, while the secondary dataset presents tadpole abundance data collected at times other than these core sampling bouts. Results of the mesocosm experiment revealed dual trophic cascades triggered by mole salamanders, highlighting the pervasive, multi-channel influence of predators across all trophic levels in pond communities.

### Files and variables

#### **File: PredationAltersCommunityStructure2024\_Data.csv**

**Description:** Data collected in each mesocosm during the study period of...,