Black garden ants reduce aphid predation by native and invasive ladybirds

We established microcosms with a bean plant (Vicia faba) infested with black bean aphids (Aphis fabae). The microcosms were divided into the following treatments: no ants, aphids tended by common red ants (Myrmica rubra), and aphids tended by black garden ants (Lasius niger). We added either a native ladybird (Coccinella septempunctata) or an invasive ladybird (Harmonia axyridis) to the microcosms. We compared deterrence of ladybirds from plant-based aphids by ants and the number of aphids remaining at the end of the experiment. We present the data of remaining aphids [Aphids] and observations of ladybirds on plants [Plant] in two versions: 1) data_all: with the respective variables in one single column and observation [Observ] as an additional variable and 2) data_per_observ: presenting the measured variables in individual columns for the respective time of observation (h after the start of the experiment). Explanatory variables include the identity of the microcosm [No], experimental ..., , # Data from: Black garden ants reduce aphid predation by native and invasive ladybirds

Dataset DOI: [10.5061/dryad.j6q573nsc](10.5061/dryad.j6q573nsc)

## Description of the data and file structure

Background

Intraguild interference between predators can hamper top-down regulation. For example, aphid-tending ants often defend their mutualistic partners against antagonists. Greater ant aggression against native ladybirds compared to non-native ladybirds might benefit the non-native predator, due to predator-predator naïveté. As a consequence, non-native ladybirds are expected to consume more aphids and might thus outcompete native ladybirds.

Methods

We established microcosms with a bean plant (*Vicia faba*) infested with black bean aphids (*Aphis fabae*). The microcosms were divided into the following treatments: no ants, aphids tended by common red ants (*Myrmica rubra*) and aphids tended by black garden ants (*Lasius niger*). We added either a native ladybird (*Coccinella septempu...,