Dataset Overview

This dataset includes stable isotope measurements, otolith microchemistry data, and trap monitoring records for brook trout (Salvelinus fontinalis). Samples were collected across multiple stream sections and years to investigate interannual variation in anadromous behavior.

The dataset contains both raw and processed data, as well as statistical outputs used in the associated publication.

This file corresponds to the data set submitted here as: dryad_v2_May.zip

Methods Summary

Stable isotope ratios (δ¹³C, δ¹⁵N, δ³⁴S) were measured from egg samples to infer maternal resource use. Otolith microchemistry was quantified using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), generating elemental concentration profiles. Trap monitoring recorded alevin emergence dynamics across sites.

Detailed methodological descriptions are provided in the associated publication.

File Inventory

The dataset includes the following files:

1. egg_stable_isotopes_dryad
2. Raw_trapsdata_dryad
3. 1st2nd_3rdsample_microchemistry
4. Otolith186_dryad
5. Egg Isotopic Analysis
6. Otolith Analysis

File Descriptions

1. egg_stable_isotopes_dryad_ok

This file contains stable isotope ratios measured from brook trout eggs.

• Isotopes analyzed: δ¹³C, δ¹⁵N, δ³⁴S
• Sampling locations:
  • LW: Lower Coles Creek
  • UP: Upper Coles Creek
  • SV: Springvale
• Sampling years: 2021, 2022
• Cluster variable (contingent classification):
  • A: Freshwater
  • B: Pelagic
  • C: Benthic

Columns include:

• Year: sampling year
• Sampling Location: LW, UP, SV
• Cluster: A, B, C
• 13C: δ¹³C, 15N: δ¹⁵N,  34S: δ³⁴S (‰)
• C(%), N(%), S(%): elemental proportion (%)
• CN: carbon-to-nitrogen ratio
• Egg: Egg diameter (mm)

2. Raw_trapsdata_dryad_ok

This file contains raw data on brook trout alevin emergence from multiple trap locations.

Sheet: emergence2021

• Date: monitoring date
• Trap: identify each monitored trap with emergent alevins
  • Collums: Tco1–Tco10: traps located in Coles Creek (locations 1–10)
  • Columns: Tm1–Tm3: traps located in Milton Creek (locations 1-3)
  • Colum’s: Tsv1–Tsv7: traps located in Springvale Creek (locations 1-7)
• Each row represents the number of alevins captured per trap on a given date

Sheet: alltraps2023

• Year: monitoring year
• Date: sampling date
• Site: Location where traps were deployed and checked (e.g., Lower Coles Creek)
• Trap ID: identifier of each trap (TP1, TP2, TP3)
• Checked (Y/N): indicates presence or absence of alevins
• Alevin (n) count: register the number of alevins captured
• Length (mm): length of captured alevins

Sheet: alevindata_2021

• Date of sampling: monitoring date
• Trap: identifier of each trap (Tco1): in Coles Creek
• ID: unique identifier for each individual alevin
• Length (mm): alevin individual length
• This sheet contains length measurements from a subsample of alevins collected in 2021 from a single trap Tco1

3. 1st2nd_3rdsample_microchemistry_ok

This file contains raw otolith microchemistry data for brook trout young-of-the-year (YOY): otolith samples.

• Data type: elemental concentrations (21 elements)
• Units: parts per million (ppm)

Sheet: DEC2123_raw: this is the 1stsample for microchemistry

• Sample pack: identifies the analytical batch
• Sample ID: individual otolith identifier
• Absolute time: date–time of ablation: Date: time
• Elapsed time: time since the start of the process (seconds)
• Elemental concentrations (ppm): Li⁷⁷, B¹¹, Na²³, Mg²⁴, P³¹, Cl³⁵, K³⁹, Ca⁴⁴, V⁵¹, Cr⁵², Mn⁵⁵, Fe⁵⁶, Co⁵⁹, Ni⁶⁰, Cu⁶³, Zn⁶⁶, As⁷⁵, Rb⁸⁵, Sr⁸⁸, Ba¹³⁷, Pb²⁰⁸

Sheet: JAN_raw: this is the 2nd sample for microchemistry

• Pack ID: identifies the analytical batch
• Sample ID: individual otolith identifier

• Absolute time: date–time of ablation: Date:time

• Elapsed time: time since the start of process (seconds)

• Elemental concentrations (ppm): Li⁷⁷, B¹¹, Na²³, Mg²⁴, P³¹, Cl³⁵, K³⁹, Ca⁴⁴, V⁵¹, Cr⁵², Mn⁵⁵, Fe⁵⁶, Co⁵⁹, Ni⁶⁰, Cu⁶³, Zn⁶⁶, As⁷⁵, Rb⁸⁵, Sr⁸⁸, Ba¹³⁷, Pb²⁰⁸

Sheet: APR_raw: this is the 3^rd sample for microchemistry

• Sample package identifies the analytical batch
• Sample ID: individual otolith identifier
• Absolute time: date–time of ablation: Date:time
• Elapsed time: time since the start of process (seconds)
• Elemental concentrations (ppm): Li⁷⁷, B¹¹, Na²³, Mg²⁴, P³¹, Cl³⁵, K³⁹, Ca⁴⁴, V⁵¹, Cr⁵², Mn⁵⁵, Fe⁵⁶, Co⁵⁹, Ni⁶⁰, Cu⁶³, Zn⁶⁶, As⁷⁵, Rb⁸⁵, Sr⁸⁸, Ba¹³⁷, Pb²⁰⁸

Sheet: Fulldata raw: this is the  1^st, 2^nd, 3^rd sample for microchemistry combined

• Combined dataset including all three analytical batches

Columns include:

• Pack ID: identifies the three analytical batch: DEC2123_raw, JAN_raw, APR_raw
• Code: identifies batch order (1st, 2nd, 3rd)
• Sample ID: individual otolith identifier
• Absolute time: date–time of ablation: Date:time
• Elapsed time: time since the start of process (seconds)
• Elemental concentrations (ppm): Li⁷⁷, B¹¹, Na²³, Mg²⁴, P³¹, Cl³⁵, K³⁹, Ca⁴⁴, V⁵¹, Cr⁵², Mn⁵⁵, Fe⁵⁶, Co⁵⁹, Ni⁶⁰, Cu⁶³, Zn⁶⁶, As⁷⁵, Rb⁸⁵, Sr⁸⁸, Ba¹³⁷, Pb²⁰⁸

4. Otolith186_dryad_ok

This file contains processed otolith elemental data.

• Elements analyzed: Sr, Ba, Pb (normalized to Ca)

Columns include:

• Year: sampling year: 2021-2022-2023
• Section: stream section
• Reach: sampling location nested within section
• ID: individual fish identifier
• Weight (g): brook trout individual weight, registered in grams
• Sr, Ba, Pb: element-to-Ca ratios
• LogSr, LogBa, LogPb: log10-transformed ratios
• Group: contingent classification (Marine, Estuarine, Freshwater)

Section codes:

• LW: Lower Coles Creek
• UP: Upper Coles Creek
• SV: Springvale

Reach Codes:

• LW: 1-3
• MID: 1-3 (* note: reaches denominated MID are also nested within the  LW section)
• UP:1, 3 -4
• SV: 1-3

Folder: egg_isotope_analysis

5. Egg_Isotopic_Analysis

This workbook contains statistical outputs derived from egg isotope data (converted from STATISTICA, .stw format into Excel .xls).

Sheet: Descriptive_isotopeallyrs

• Descriptive analysis for the mean value for each isotope:  δ¹³C, δ¹⁵N, and δ³⁴S grouped by clusters A, B, and C. Indicating: mean, number of samples, and standard error (SE) for each element in each cluster.

Sheet: Analysis of Variance isotope

• A parametric test of Analysis of variance (ANOVA) results for isotope data from the egg samples. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), SS(error) and df(error), MS (error), F-statistic, and p value of significance for each variable: 13C, 15N, 34S.

Sheet(s): TukeyHSD_13C, TukeyHSD_15N, TukeyHSD_34S

• A Post hoc Tukey Honestly Significant Difference (HSD) test for each isotopic element (13C, 15N, 34S) between the clusters.

Sheet: Descriptive_eggclust

• Descriptive analysis for the mean value for egg diameter grouped by cluster. Indicating: mean, number of samples, standard deviation (SD), and standard error (SE), for each cluster.

Sheet: Analysis of Variance_egg

• A parametric test of Analysis of variance (ANOVA) for egg diameter from the egg samples data. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), SS(error) and df(error), MS (error),  F-statistic, and p value of significance for the variable.

Sheet: Tukey HSDtest_egg_clust

• A Post hoc Tukey Honestly Significant Difference (HSD) test for the egg diameter between clusters.

Sheet: Descriptive egg_location

• Descriptive analysis for the mean value for egg diameter grouped by sections. Indicating: mean, number of samples, standard deviation (SD), and standard error (SE), for each Location.

Sheet: Analysis_of_Var_egg_location

• A parametric test of Analysis of variance (ANOVA) for egg diameter between the locations. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), SS(error), df(error), MS (error), F-statistic, and p value of significance for the variable.

Sheets:GLM_anadrom_x_location

A two-way factorial ANOVA (univariate general linear model).

• Dependent variable: egg diameter
• Categorical variables: Anad and location
• Two main effects are present: ANAD and Location.
• An interaction term is explicitly included: ANAD × Location.
• Each effect has associated SS, df, MS, F, and p, consistent with ANOVA decomposition.

NOTE: ANAD is the categorical variable indicating anadromous.

Sheet: GLM_anadrom_location

A two-way ANOVA without interaction (additive model in a univariate GLM).

• Dependent variable: egg diameter
• Two factors are included: Cluster (3 levels) and Location (3 levels).
• Only main effects are tested
• Each effect is evaluated using F-statistics and p-values

Sheet: GLM_cluster_x_location

A two-way factorial ANOVA (univariate general linear model).

• Dependent variable: egg diameter
• Categorical variables: Cluster and location
• Two main effects are present: Cluster and Location.
• An interaction term is explicitly included: Cluster × Location.
• Each effect has associated SS, df, MS, F, and p, consistent with ANOVA decomposition.

Sheet: GLM_cluster_location

A two-way ANOVA without interaction (additive model in a univariate GLM).

• Dependent variable: egg diameter
• Two factors are included: Cluster (3 levels) and Location (3 levels).
• Only main effects are tested
• Each effect is evaluated using F-statistics and p-values

Folder: otolith_analysis

6. Analysis_otolith_dryad

This workbook contains statistical outputs derived from Otolith186_dryad (converted from STATISTICA, .stw format into Excel .xls).

Sheet: Descriptive otolith all years

• Descriptive analysis for the mean value for each element:  Sr⁸⁸, Ba¹³⁷, Pb²⁰⁸ by group: Estuarine, Freshwater, Marine. Indicating: mean, number of samples, standard deviation (SD), and standard error (SE) for each element in each group.

Sheet: Test_weight_group_sect2022

A two-way factorial ANOVA (univariate general linear model). * Data used in this analysis were from the year 2022.

• Dependent variable: brook trout YOY weight
• Categorical variables: Section and group
• Two main effects are present: Section and group.
• An interaction term is explicitly included: Section x group
• Each effect has associated SS, df, MS, F, and p, consistent with ANOVA decomposition.

Sheet: Test_weight_sectgroup2022

A two-way ANOVA without interaction (additive model in a univariate GLM): (2022 only)

• Dependent variable: brook trout YOY weight
• Two factors are included: Group (3 levels) and Section (3 levels).
• Only main effects are tested
• Each effect has associated SS, df, MS, F, and p, consistent with ANOVA decomposition

Sheet: TukeyHSDtestweight2022

• A Post hoc Tukey Honestly Significant Difference (HSD) test for the brook trout YOY weight between sections in the year 2022.

Sheet: Descriptive_weight_clust2022

• Descriptive analysis for the mean value for brook trout YOY weight by group: Estuarine, Freshwater, Marine. Indicating: mean, number of samples, standard error (SE), standard deviation (SD), for each section.

Sheet: ANOVA_SR_2022

• ANOVA for Sr⁸⁸ between groups (2022)
• A parametric test of Analysis of variance (ANOVA), for Sr⁸⁸ between the groups, in the year 2022. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), F-statistic, and p value of significance.

Sheet: Tukey HSD_Sr_2022

• A Post hoc Tukey Honestly Significant Difference (HSD) test for the Sr88 values between groups in the year 2022.

Sheet: ANOVA_Ba_2022

• A parametric test of Analysis of variance (ANOVA), for Ba¹³⁷ between the groups, in the year 2022. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), F-statistic, and p value of significance.

Sheet: Tukey HSD_Ba_2022

• A Post hoc Tukey Honestly Significant Difference (HSD) test for the Ba¹³⁷ values between groups in the year 2022.

Sheet: ANOVA_Pb_2022

• ANOVA for Pb²⁰⁸ between groups (2022)

A parametric test of Analysis of variance (ANOVA), for Pb²⁰⁸ between the groups, in the year 2022. Indicating:  Sum of squares (SS), degrees of freedom (df), Mean squares (MS), F-statistic, and p value of significance

Sheet: Tukey HSD_Pb_2022

• A Post hoc Tukey Honestly Significant Difference (HSD) test for the Pb²⁰⁸ values between groups in the year 2022.

Data Structure Notes

• Reaches are spatially nested within sections.
• Analytical batches in microchemistry data correspond to separate laboratory runs.
• Processed otolith data include element:Ca ratios and log-transformed variables for statistical analysis.

Notes

• “Alevin” refers to newly hatched brook trout prior to yolk sac absorption.
• Abbreviations are consistent across files unless otherwise specified.
• Samples correspond to brook trout young of the year otoliths.

Reuse Considerations

• Raw and processed datasets are provided separately; users should verify which version is appropriate for their analyses.
• Statistical output files are included for transparency but are not required for independent analyses.
• Full methodological details and analysis are available in the associated publication.