Temporal effects of preservation on the shape and size of yellow perch: Implications for morphological analyses

Long-term preservation of fishes often involves fixation in formalin followed by preservation in ethanol. This preservation technique can alter the shape and size of specimens, although the effects are often species and stage specific. In this study, we evaluated the temporal effects of preservation on shape and body size of adult Yellow Perch (Perca flavescens). We sampled 42 Yellow Perch from three lakes directly connected to Lake Michigan, USA. Upon capture, fish were transported to the laboratory, fixed in formalin, and then preserved in ethanol. Measurements (length, mass, and photograph to analyze shape) were made on fresh fish (i.e., prior to preservation) and 21, 47, and 61 days after being preserved in ethanol. Shape was analyzed using geometric morphometrics. We identified significant changes in shape and to a lesser degree size. The most significant shape change occurred in the comparison of pre-preserved vs. 21 days, with most of this variation attributed to dorsal bending. ..., Physical measurements (total length and body mass) were measured in the lab and were recorded in Microsoft Excel. Photos for geometric morphometrics, and length and mass measurements within Excel spreadsheets were uploaded to R Programming, where they were analyzed. Landmarks were placed on the digital photographs in R.
, , # Temporal effects of preservation on the shape and size of yellow perch: Implications for morphological analyses

[https://doi.org/10.5061/dryad.cfxpnvxhs](https://doi.org/10.5061/dryad.cfxpnvxhs)

## Description of the data and file structure

Total length, wet mass, and photographs were taken at four time periods for each of the three lakes. Measurements and photographs were uploaded to R where they were further processed.

.tps file label format follows two letter lake code (AL, WL, or MA) for Arcadia Lake, White Lake, and Macatawa Lake, the FishID number, the word day, followed by the day of preservation. For example, AL46day47.tps would be fish number 46 from Arcadia Lake on day 47 of preservation.

Each  .tps file contains the coordinates for each of the 13 landmarks, along with the scale and FishID.

### Files and variables

Files (TPS_files.zip): AL46day47.tps, AL45WK3.tps, AL45Day61.tps, AL45day47.tps, AL44day61.tps, AL45DOC.2.tps, AL44day47.tps, AL44WK3.tps, MA66day61.tps, MA...,