README: Inter and intrapopulation resource use variation of marine subsidized western fence lizards

Authors: Alexi Ebersole1, Marie E. Bunker1, Stacey L. Weiss1, Kena Fox-Dobbs2

Department of Biology1 and Geology2 University of Puget Sound, Tacoma, WA, USA 98416

## Data collection methods overview

* We collected data from seven western fence lizard (Sceloporus occidentalis) populations across 3 different habitats in Washington State, USA. For stable isotope analysis, we removed a small piece of tail tissue from the lizards which we processed between the University of Puget Sound, University of Washington Stable Isotope Laboratory, and the University of Colorado Boulder Earth Systems Stable Stable Isotope Laboratories. We collected arthropod prey and plant samples for stable isotope analysis and lizard diet reconstruction. We measured lizard body length and weight data by hand using rulers and spring scales in the field. To model the diets of lizards and quantify marine diet contribution, we used the MixSIAR R package and alpha value equation using our lizard tissue, prey, and plant stable isotope data.We used the SIBER R package to compare the isotopic niche space of lizard populations, and also used Google Earth imagery to examine the slope of transition zone between marine and terrestrial environments.

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## Included files:

lizard_data.csv: Includes raw carbon and nitrogen stable isotope data for western fence lizard (Sceloporus occidentalis) lizard tissue samples used in the study, lizard body size and length data, in addition to statistical analyses quantifying marine diet contributions

# Site - The name of the S. occidentalis study population in Washington State

# Lizard ID - The unique toe-clip number assigned to individual S. occidentalis

for identification and recapture purposes

# δ13C (permil) - The carbon stable isotope ratio (13C:12C) of S. occidentalis tail tissue

# weight %C - The percent weight of carbon contained in the S. occidentalis tail tissue sample

# δ15N (permil) - The nitrogen stable isotope ratio (14N:15N) of S. occidentalis tail

tissue

# weight %N - The percent weight of nitrogen contained in the S. occidentalis tail

tissue sample

# C/N ratio - The ratio by weight of carbon versus nitrogen contained in the S. occidentalis tail tissue sample

# % marine diet MixSIAR (claw&claw TEF) - the percent of diet from marine derived nutrients for individual S. occidentalis, estimated with the MixSIAR R package, using claw Δ13Ctissue-diet, and claw Δ15Ntissue-diet diet to tissue discrimination values

# % marine diet MixSIAR (skin&claw TEF) - the percent of diet from marine derived nutrients for individual S. occidentalis, estimated with the MixSIAR R package, using skin Δ13Ctissue-diet, and claw Δ15Ntissue-diet diet to tissue discrimination values

# % marine diet alpha - the percent of diet from marine derived nutrients for individual S. occidentalis, estimated with the alpha equation: ? = {[(δ13Cconsumer – Δ13C) – δ13Cterrestrial]/(δ13Cmarine – δ13Cterrestrial)}*100

# sex - the sex of the lizard was determined (M = male, F = female) using the post anal scales of the lizard

# svl.mm - the snout to vent length of the lizard in millimeters

#bmass.g - the body mass of the lizard in grams

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plant_data.csv: Includes raw carbon and nitrogen stable isotope data for plant samples used in the study. At the inland site we collected foliage of seven abundant grass taxa to confirm the absence of C4 vegetation. Algae and blackberry samples were used in the alpha equation to calculate the contribution of marine resources in lizard diets

# Site - the name of the S. occidentalis study population in Washington State

# Sample ID - the name of plant sample

# δ13C (permil) - the carbon stable isotope ratio (13C:12C) of the plant sample

# weight %C - the percent weight of carbon contained in the plant sample

# δ15N (permil) - the nitrogen stable isotope ratio (14N:15N) of the plant

# weight %N - the percent weight of nitrogen contained in the plant sample

# C/N ratio - the ratio by weight of carbon versus nitrogen contained in the plant sample

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prey_data.csv: Includes raw carbon and nitrogen stable isotope data for arthropod prey item samples used in the study for lizard diet reconstruction and analyses

# Site - the name of the S. occidentalis study population in Washington State

# Sample ID - the name of the arthropod prey item sample. For example, “LCB.tidal.arth1” refers to a intertidal arthropod collected along the shoreline at the Lower Chambers Bay study site, while “LCB.terrest.arth7” refers to a terrestrial arthropod collected above the wrack line on the bank at Lower Chambers Bay.

# Family - the taxonomic family of the arthropod samples

# δ13C (permil) - the carbon stable isotope ratio (13C:12C) of the arthropod sample

# weight %C - the percent weight of carbon contained in the arthropod sample

# δ15N (permil) - the nitrogen stable isotope ratio (14N:15N) of the arthropod

# weight %N - the percent weight of nitrogen contained in the arthropod sample

# C/N ratio - the ratio by weight of carbon versus nitrogen contained in the arthropod sample

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transition_zone.csv: The slope of the transition zone between marine and terrestrial environments (e.g., unvegetated bluff, open meadow, coastal forest) calculated as the elevation relief along five 75 m transects that extended inland perpendicular from sea level (0 m asl) along the shoreline where lizards were captured. Measurements were repeated 5 times at each study site.

# Site - the name of the S. occidentalis study population in Washington State

# Transition zone slope - the rise/run of the transition zone between marine and terrestrial environments along 75 m transects. Calculated using Google Earth imagery.

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siber_data.csv: Includes data from the Stable Isotope Bayesian Ellipses in R (SIBER) package that we used to estimate and compared the isotopic niche space of the beach lizard populations

# Site - the name of the S. occidentalis study population in Washington State

# SEAc - The “Standard Ellipse Area” (SEA) of S. occidentalis populations calculated with the SIBER package in R, that is corrected for small sample sizes to estimate isotope niche space (SEAc).

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Additional notes:

* “.” signifies missing data in the spreadsheet