Effects of freezing on white perch Morone americana (Gmelin, 1789): Implications for multivariate morphometrics

Journal of Applied Ichthyology



This study tested the hypothesis that duration of freezing differentially affects whole-body morphometrics of a derived teleost. Whole-body morphometrics are frequently analyzed to test hypotheses of different species, or stocks within a species, of fishes. Specimens used for morphometric analyses are typically fixed or preserved prior to analysis, yet little research has been done on how fixation or preservation methods or duration of preservation of specimens might affect outcomes of multivariate statistical analyses of differences in shape. To determine whether whole-body morphometrics changed as a result of freezing, 23 whole-body morphometrics of age-1 white perch (Morone americana) from western Lake Erie (n = 211) were analyzed immediately after capture, after being held on ice overnight, and after freezing for 100 or 200 days. Discriminant function analysis revealed that all four groups differed significantly from one another (P < 0.0001). The first canonical axis reflected long-axis morphometrics, where there was a clear pattern of positive translation along this axis with duration of preservation. Re-classification analysis demonstrated fish were typically assigned to their original preservation class except for fish frozen 100 days, which assigned mostly to frozen 200 days. Morphometric comparisons using frozen fish must be done on fish frozen for identical periods of time to avoid biases related to the length of time they were frozen. Similar experiments should be conducted on other species and also using formalin- and alcohol-preserved specimens.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Effects of freezing on white perch Morone americana (Gmelin, 1789): Implications for multivariate morphometrics
Series title Journal of Applied Ichthyology
DOI 10.1111/jai.12930
Volume 32
Issue 1
Year Published 2016
Language English
Publisher Wiley-Blackwell
Publisher location Berlin
Contributing office(s) Great Lakes Science Center
Description 5 p.
First page 92
Last page 96
Country Canada, United States
Other Geospatial Western Lake Erie
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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