Title: Determining sex and life stage of Del Norte salamanders from external cues
Author: Ollivier, Lisa; Welsh Jr, Hartwell H.
Date: 2003
Source: Northwestern Naturalist, Vol. 84: 129-134
Description: Life stage determination for many western plethodontids often requires dissection of the specimen. Availability of reliable external measures that could be applied under field conditions would enhance future studies of the genus Plethodon. We examined preserved specimens of the Del Norte Salamander, Plethodon elongatus, taken from 11 sites in northwestern
California and southwestern Oregon. During the dissections, we recorded several external body characteristics that could prove useful in determining the life stage and gender of individuals. Identification of life stage is possible by using several external measurements. A discriminant function model including snout vent length, weight, head length, and width correctly classified life stage 92% of the time. A tree-based classification analysis identified snout-vent length as a single variable that could correctly classify life stage 90.2% of the time. We also have identified a sexually dimorphic character for adults, vent pattern and coloration, that can reliably distinguish gender at any time of year.
Keywords: Plethodon elongatus, Del Norte salamander, morphometrics, tree-based classification, gender determination, life stage determination
View and Print this Publication (440 KB)
Pristine Version: An uncaptured or "pristine" version of this publication is available. It has not been subjected to OCR (Optical Character Recognition) and therefore does not have any errors in the text. However it is a larger file size and some people may experience long download times. The "pristine" version of this publication is available here:
View and Print the PRISTINE copy of this Publication (590 KB)
Publication Notes:
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility
Citation
Ollivier, Lisa; Welsh Jr, Hartwell H. 2003. Determining sex and life stage of Del Norte salamanders from external cues. Northwestern Naturalist, Vol. 84: 129-134.