The Relationship among Stream Order, Length of the Larval Period, and Metamorphosis in the Salamander Eurycea wilderae
Voss SR. 1988. The Relationship among Stream Order, Length of the Larval Period, and Metamorphosis in the Salamander Eurycea wilderae. Western Carolina University
The seasonal pattern of metamorphosis according to age and body size was elucidated for Eurycea wilderae larvae at four southern Appalachian drainages. At each drainage, a small first-order tributary was paired with an adjacent higher-order section of the main stream. A bimonthly sampling program during the summer showed that larvae metamorphosed after 1-yr in all first-order streams except one, while in larger streams larvae metamorphosed after 1 or 2-yr. The length of the metamorphic season varied between and within drainages. Also inter- and intra-populational variation in the body size of metamorphosing larvae was observed, with smaller body sizes recorded for metamorphosing larvae in the first-order streams. In all populations studied, there was a decrease in mean metamorphic size during the summer. Hatchling larvae appeared in first-order streams at an earlier date. This appears to be the result of temperature differences between first-order and higher-order streams. Because first-order streams are warmer than higher-order streams in the winter, adult females are probably cued to oviposit earlier. This leads to an extended growing season for larvae in first-order streams. Also, a seasonal shift in stream temperature was more pronounced in higher-order streams than in first-order streams. The more uniform temperature conditions in first-order streams may allow larvae to complete development after 1 year and initiate metamorphosis.
- Type
- Academic
- Authors
- Voss, Stephen
- Date of Issue
- 1988-05
- Publisher
- Western Carolina University
- Units
- GRSM
- Keywords
- APHN, Appalachian Highlands Network, Great Smoky Mountains National Park, GRSM, GRSM-01853, larval period, metamorphosis, Salamander, SER, Southeast Region, Straight Fork, stream order, thesis
- Subjects
- Ecological Framework: Biological Integrity | Focal Species or Communities | Amphibians and Reptiles