Dataset DOI: 10.5061/dryad.3ffbg79zk

Author contact: Darren.johnson@csulb.edu

Description of the data and file structure

These data come from a mark-recapture study of wavy turban snails in Southern California, USA. Field studies took place between June 2022 and March 2024. Snails were subject to repeated behavioral assays in the laboratory in order to measure repeatability of exploration and risk-taking behaviors. The same snails were tagged and released into the field to measure growth and survival over a ~6-month period.

In all of the data files, an entry of "NA" indicates that data were not available. In most cases, this was because a subset of measurements was not taken. For example, a few snails in the mark-recapture study had not been assayed for all behaviors. 

Similarly, in the data files summarizing somatic growth, some snails are marked as "DEAD." Although these were infrequent occurrences, tagged shells were occasionally re-encountered in the field (and often occupied by hermit crabs). These data were not used to measure growth of snails, but they were still useful for measuring rate of tag overgrowth and so were retained in the dataset. 

Files and variables

File: Tag_loss_estimation.csv

Description: Data used to estimate rates of tag loss at each of the four study locations. All snails began with two tags on opposite sides of the body. Comparing the proportion of snails being recaptured with a single tag at various times can be used to estimate the rate of tag loss.

Variables

• Location: Field location 
• Date Group Released: Date of release (month/day/year)
• Interval: Days between initial release and recapture date
• Recovered.double: Number of recaptured snails that had two tags remaining
• Recovered.single: Number of recaptured snails that had only one tag remaining

File: Emergence_behavior.csv

Description: Summary of repeated behavioral assays within the laboratory. Our measure of risk-taking was the time it took the snail to emerge from a simulated threat.

Variables

• ID: Identifier number. Early in the study snails were given two tags with different numbers. Later on, we gave snails two tags with the identical number. In these cases only a single number is listed as the ID
• Emergence.time: Time in seconds until the snail emerged from an operculum-closed state
• Date: Date of assay (month/day/year)
• Pokes: Number of touches with a probe before the snail fully closed its operculum
• Temperature: Temperature of water in the arena during the behavioral trial. Recorded in Celsius
• Observer: Name of observer
• Trial.Number: Snails were subject to multiple assays. 
• Diameter: Diameter of the bottom of the shell, in millimeters
• Site: Location of source population

File: Exploration_behavior.csv

Description: Summary of repeated behavioral assays within the laboratory. Exploration was measured as the total distance traveled in a 10-minute period

Variables

• ID: Identifier number. Early in the study snails were given two tags with different numbers. Later on, we gave snails two tags with the identical number. In these cases only a single number is listed as the ID
• Dist.moved: Total distance traveled in centimeters
• Water.Temp: Water temperature during the trial. Recorded in Celsius
• Trial.Number: Trial number
• Diameter: Diameter of the bottom of the shell, in millimeters
• Site: Location of source population

File: Encounter_History_Bailey.csv; File: Encounter_History_Cherry.csv;

File: Encounter_History_Isthmus.csv; File: Encounter_History_White_s.csv

Description: Encounter histories used in mark-recapture studies.

Variables

• ID: Tag number used to identify individual snails

• Diameter: Diameter of the bottom of the shell, in millimeters

• Mass: Mass of snail (including shell) in g

• Tag.Date: Date snail was tagged (month/day/year)

• Date.Released: Date of release into field population (month/day/year)

  Next columns are Census data by date. For each census, snails were given a value of 0 if absent, 2 if present and alive with 2 tags remaining, and a value of 1 if present and alive with only 1 tag remaining

• Notes: Field notes identifying snails that were confirmed dead (e.g. empty shells), tag loss, etc.

File: Recapture_Growth_Bailey.csv; File: Recapture_Growth_Cherry.csv;

File: Recapture_Growth_Isthmus.csv; File: Recapture_Growth_White_s.csv

Description: Data files summarizing field measurements of size that were used to measure growth of snails.

We note that some snails were marked as DEAD. Tagged shells were occasionally re-encountered in the field (and often occupied by hermit crabs). These data were not used to measure growth of snails, but they were still useful for measuring rate of tag overgrowth and so were retained in the dataset. 

Variables

• ID: Tag number used to identify individual snails
• Release.Date: Date of release and first set of size measurements (month/day/year)
• Recapture.Date: Date of release and second set of size measurements (month/day/year)
• Diam.Release: Diameter at time of release. Measured in mm.
• Mass.Release: Mass at time of release. Measured in g.
• Diam.Recapture: Diameter at time of recapture. Measured in mm.
• Mass.Recapture: Mass at time of recapture. Measured in g.
• Tag.1.State: Degree of overgrowth. 0 = tag completely clear; 1 = tag completely overgrown and no longer visible. 
• Tag.2.State: Degree of overgrowth. 0 = tag completely clear; 1 = tag completely overgrown and no longer visible. 
• Tag.Total: Average degree of overgrowth between tags 1 and 2
• Tag.Min: Minimum tag overgowth 
• Interval: Number of days between release and recapture
• Avg.size: Mean diameter of snails between release and recapture
• Growth.per.day: Change in shell diameter (in millimeters / day)
• Initial.Release: Date when snail was first placed in the field. Some snails were recaptured two or more times. Each time, the snails were released back to their habitat. 'Release date' refers to most recent release. 
• Tag.Age: Total number of days since the snail and its tag were initially released to the field population.

Code/software

Data are archived as csv files. No special software is needed to view them. Analytical procedures are described in the associated publication.