DOI: 10.5061/dryad.kh1893250
title: Community-wide consequences of nonconsumptive predator effects on a foundation species

description: 1. Predators can exert nonconsumptive effects (NCEs) on prey, which often
 take place through prey behavioural adjustments to minimize predation
 risk. As NCEs are widespread in nature, interest is growing to determine
 whether NCEs on a prey species can indirectly influence several other
 species simultaneously, thus leading to changes in community structure. 2.
 In this study, we investigate whether a predator can exert NCEs on a
 foundation species and indirectly affect community structure. 3. Through
 laboratory experiments, we first tested whether the predatory marine snail
 Acanthina monodon exerts negative NCEs on larviphagy (consumption of
 pelagic larvae) and phytoplankton filtration rates of the mussel
 Perumytilus purpuratus, an intertidal foundation species. These hypotheses
 stem from the notion that mussels may decrease feeding activities in the
 presence of predator cues to limit detection by predators. Afterwards, a
 field experiment tested whether the presence of A. monodon near mussel
 beds leads to higher colonisation rates of invertebrates that reproduce
 through pelagic larvae (expected under a lower larviphagy in P.
 purpuratus) and to a lower algal biomass on P. purpuratus shells (expected
 under a lower metabolite excretion in the mussels), thereby changing the
 community structure of the species typically found in P. purpuratus beds.
 4. The laboratory experiments revealed that waterborne cues from A.
 monodon limit the larviphagy and filtration rates of P. purpuratus. In
 turn, the field experiment showed that A. monodon cues led to greater
 abundances of barnacles and bivalves and a lower algal biomass in P.
 purpuratus beds, thus altering community structure. 5. Overall, this study
 shows that a predator can indirectly affect community structure through
 NCEs on an invertebrate foundation species. As invertebrate foundation
 species are ubiquitous worldwide, understanding predator NCEs on these
 organisms could help to better understand community regulation in systems
 structured by such species. 12-Feb-2021
description: Descriptions of how the data were collected are written in full
 in the Methods section of the manuscript.
description: The data is saved as three separate files contain the results of
 laboratory and field based experiments. The experiments used the same two
 treatments: predator presence (A+) and absence (A-). 
 1. Larviphagy_rate_data.xls contains the results of a laboratory
 experiment in which we tested the larviphagy rate of <em>Perumytilus
 purpuratus</em> (number of larvae eaten per individual per hour)
 under <em>Acanthina monodon</em> presence (A+) and absence
 (A-). 2. Filtration_rate_data.xls contains the results
 of a laboratory experiment in which we tested the phytoplankton filtration
 rate of <em>P. purpuratus</em> (litres of water filtered per
 individual per hour) under <em>A. monodon</em> presence (A+)
 and absence (A-). 3. Field_experiment_data.xls contains
 the results of a field manipulative experiment in which we determine the
 community structure of species associated to <em>P.
 purpuratus</em> beds under <em>A. monodon </em>presence
 (A+) and absence (A-). The density of the associated invertebrate species
 was calculated as the number of organisms per experimental unit. The algal
 biomass was quantified as algae wet weight (mg) per experimental
 unit.