DOI: 10.5061/dryad.pzgmsbct7
title: Individual survival is dictated by group personality in a marsh ecosystem predator-prey interaction

description: Predator–prey interactions structure ecological communities, and
 personality can significantly mediate these interactions. Personality
 expression is often contingent on social context, suggesting that group
 personality may be key in determining the outcomes of predator encounters.
 Here we test the influence of individual personality and group composition
 on survival of the marsh periwinkle, Littoraria irrorata, when exposed to
 its main predator, the blue crab, Callinectes sapidus, both integral
 players in mediating the productivity and health of salt marsh ecosystems.
 Personality varied along a bold-shy continuum and was unrelated to shell
 length, though neither trait influenced survival when individual snails
 were exposed to a predator. However, when snails were partitioned into
 groups differing in personality composition, snails in groups with bold
 individuals had higher survival than those in groups with none. While
 group type did not influence the survival of bold snails, shy snails
 performed significantly better in mixed groups: the presence of a few bold
 individuals emerged as especially effective in decreasing mortality of shy
 snails. The effect of personality on predator escape is thus conditional
 on group personality composition, indicating that social context can
 directly impact the survival and success of its individual members, with
 broad implications for community dynamics. 
description: <em>Littoraria irrorata</em> were haphazardly
 collected from a salt marsh at UNCW’s Center for Marine Science (34.1418°
 N, 77.8674° W). They were transferred indoors and housed in groups of 15 within mesh containers
 (14.60cm x 7.6cm, 0.95L) that sat on a platform in a 37.85L
 aquarium at a height which allowed each
 container to have access to both 3 cm of seawater and 6 cm of
 air. In each trial, five snails were
 placed in a single 11.4L bucket (d=18.5cm, h=29cm), filled with 3cm of
 high-quality seawater and two refuges. The refuges consisted of a hollow
 semi-sphere placed flush to the bottom of the bucket with an opening of
 3cm x 3cm facing the center of the bucket, which allowed snails to freely
 crawl in and out. Snails were placed in
 the center of the bucket, equidistant from one another and from the edge,
 and were allowed to acclimate for five minutes. Behavior was
 recorded every 2 minutes during the 10-minute trial and here boldness was
 calculated as the total time in 2-minute blocks where snails were outside
 the refuge. In this first set of experiments, a single
 snail and a single blue crab were simultaneously placed on opposite sides
 of the tank, and mortality was assessed after a 24-hour period. Trials
 were run on 25 shy snails and 25 bold snails using a randomly chosen blue
 crab from the set of nine that were held
 in 37.85L tanks and fed
 crushed marsh periwinkles ad lib. for the duration of the trials.
 In the second set of experiments, 20 snails and a single blue
 crab were simultaneously placed on opposite sides of the tank, and
 mortality was assessed after a 72-hour period. Here group personality
 composition was modified, resulting in five treatments: (a) 20 shy snails,
 (b) 20 bold snails, (c) 15 bold:5 shy snails, (d) 5 bold:15 shy snails,
 and (e) 10 bold:10 shy snails.
description: ## Individual survival is dictated by group personality in a marsh
 ecosystem predator-prey interaction
 [https://doi.org/10.5061/dryad.pzgmsbct7](https://doi.org/10.5061/dryad.pzgmsbct7) The dataset contains size, personality and survival data for the marsh periwinkle, *L. irrorata*, used in predation trials with the blue crab, *C. sapidus*. One dataset contains the results from individual predation trials. The second dataset contained the results from group predation trials. ## Description of the data and file structure Each row represents an individual snail. Included are testing group (snail personalities were assessed in groups of 5), shell length (mm), personality category (bold vs. shy), crab ID, trial number (for the group predation trials), tank ID, treatment group, and survival (0 = dead, 1 = alive)