DOI: 10.18710/aok1f3
title: Replication Data for: Interactive population effects of sublethal copper exposure and predation risk in a naturally stressful environment

description: The dataset contains data used in the study “Interactive population effects of sublethal copper exposure and predation risk in a naturally stressful environment
”. It contains experimental data from a mesocsom with the copepod Tigriopus brevicornis. The project was part of the MULTICOP project financed by the Norwegian Research Council (project number 301153). (2024-01-21)

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Methods
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We investigated the cumulative effects of copper and predation risk exposure on T. brevicornis over three generations. T. brevicornis is commonly found along European Atlantic shorelines and in high densities in tidal and splash water pools. The experiment was conducted at the University of Oslo Biological Research Station “Biologen” in Drøbak, Norway,. We established 36 populations by transferring 11 ovigerous T. brevicornis females from nearby splash pools into glass trays placed on the quay of the station’s harbor at th shoreline.
Two days before adding copepods, we filled each tray with 2.5 liters of seawater and their respective treatments: predation risk, copper (10 µg Cu L-1), combined, and control. Predation risk was simulated using fish kairomones. We incubated three-spined stickleback in seawater, similar to Lode et al. (2020). The 12-week experiment involved water and treatment renewals every 2 weeks. Before each renewal, we screened each microcosm for copepods (fewer than 10 or many) and other visible animals and debris. We sampled populations every 4th week by taking down 1/3 of the replicates, resulting in three independent replicates per timepoint and treatment. If possible, we randomly picked 100 individual late-stage copepodites and adults for pigment and stable isotope analysis. They were depurated in filtered seawater for two hours at ambient salinity. We then sampled adults for pigment analysis and stable isotope analysis. The remaining microcosm was filtered and preserved in 96% ethanol to determine T. brevicornis population density, structure, and abundances of other organisms. To analyze copepods’ Astaxanthin pigment content of individidual copepods, we used Thrane et al.’s (2015) spectrophotometric analysis. To calculate the specific Astaxanthin content, we used the ashfree dryweight derived from the length-weight regression for harpactcoids (Hopcroft et al., 1998). The δ15N and δ13C ratios of individual copepod samples were measured on a Thermo Fisher DeltaV Stable Isotope Mass Spectrometer configured with a Flash Elemental Analyzer Isolink system at the CLIPTlab of the Univeristy of Oslo. 

References
Hopcroft, R.R., Lombard, D., Roff, J.C., 1998. Production of tropical copepods in Kingston Harbour, Jamaica: the importance of small species. Marine Biology 130, 593–604. https://doi.org/10.1007/s002270050281

Thrane, J.-E., Kyle, M., Striebel, M., Haande, S., Grung, M., Rohrlack, T., Andersen, T., 2015. Spectrophotometric Analysis of Pigments: A Critical Assessment of a High-Throughput Method for Analysis of Algal Pigment Mixtures by Spectral Deconvolution. PLOS ONE 10, e0137645. https://doi.org/10.1371/journal.pone.0137645

Lode, Torben, Jan Heuschele, Tom Andersen, Josefin Titelman, Ketil Hylland, and Katrine Borgå. 2020. Contrasting effects of predation risk and copper on copepod respiration rates. Environmental Toxicology and Chemistry, 39(9), pp.1765-1773. https://doi.org/10.1002/etc.4804.https://doi.org/10.1002/etc.4804.



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Datafiles
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MesocosmDataHeuscheleetal.csv

ID: unique mesocosm id
Counting.order: The order in which the samples were counted.
Copper: “Copper” indicates that the treatment had added copper at a concentration of 10 ug L-1, while “No copper” was not treated with copper.
Kairomone: “Kairomone” indicates that the smell of fish was added to the treatment, while “No kairomone” indicates the lack thereof.
Date: Sampling date as d/m/y 
Month: Month
Day: Day in the year
MeanT: Average daily temperature of sampling day
maxT: maximum daily temperature of sampling day
minT: minimum daily temperature of sampling day
rangeT: daily temperature range of sampling day
ESDD needed to calculate accumulated extreme stress degree days.
ESDDaccum accumulated extreme stress degree days, i.e. days mesocosm inhabitants mesocosm likely experienced above 32 degrees.
filamentous_green_algae: amount of filamentous algae present in the mesocosms. None,Few,Many,Lots, “NA” indicates that it was not assessed
water_colour: Assessment of the color of the water in the mesocosm, “NA” indicates that it was not assessed.
salinity_psu: Salinity of the mesososm measured with a refractometer.
Nauplii: Number of Tigriopus brevicornis Nauplii 
Copepodites: Number of Tigriopus brevicornis copepodites
Copepod.with.eggsac: Number of Tigriopus brevicornis females with eggsacs
Chironomide Number of Chironomides
Other Number of other animals (dead or alive), such as drowned bumblebees, etc. 
Shorefly: Number of Ephydridae
Adults: Number of Tigriopus brevicornis adults 
AllCopepodites: Sum of copepodites and adult copepods
Allcopepods: Sum of all copepod individuals
STRESS: Stress factor 

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Concentration.animals.csv

Sample: MesocosmID
Date: Date of takedown
Month: Takedown month in the year
X: identifier
Sample.ID.new: name of the image the measurements were taken from
Imagenames: name of the image the measurements were taken from
AvgProsomeLength: prosome length in um
DWug:ash free dryweight calculated (ug)
uniqueID: unique ID of the individual
ng.well: nanogram astaxanthin in the well
Dataset: Indicating whether it is from actual animal measurements or not
Treatment: Treatment the animal was exposed to in the experiment
Plate: microwell plate id
ng.animal: ng astaxanthin per animal
Kairomone: “Kairomone” indicates that the smell of fish was added to the treatment, while “No kairomone” indicates the lack thereof.
Copper: “Copper” indicates that the treatment had added copper at a concentration of 10 ug L-1, while “No copper” was not treated with copper.
Censored: indicating whether the Astaxanthin value was below the assumed limit fo detection
AstaxanthinPerDW: Astaxanthin per animal dryweight / specific Astaxanthin mass (ng Astaxanthin per ug dry weight)


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StableIsotopeData.csv

ID: Mesocosm ID
Treatment: treatment coded as a four-level factor
Copper: “Copper” indicates that the treatment had added copper at a concentration of 10 ug L-1, while “No copper” was not treated with copper.
Kairomone: “Kairomone” indicates that the smell of fish was added to the treatment, while “No kairomone” indicates the lack thereof.
Date: Sampling date as d/m/y 
Month: Sampling month
ID2: id specific to the stable isotope analysis
c13: delta 13C isotope value
%C: percent carbon
C Notes: annotation for the carbon values (all NA)
N15: delta 15N isotope value
%N: percent nitrogen 
N Notes: annotation for the nitrogen values (all NA)