Stream Plethodontid Assemblage Response (SPAR) Index: Development, Application, and Verification in the MAHAEPA Grant Number: R827640
Title: Stream Plethodontid Assemblage Response (SPAR) Index: Development, Application, and Verification in the MAHA
Investigators: Brooks, Robert P. , Rocco, Brian L.
Current Investigators: Brooks, Robert P. , Rocco, Brian L. , Hite, Jeremy T.
Institution: Pennsylvania State University
EPA Project Officer: Packard, Benjamin H
Project Period: July 1, 1999 through June 30, 2002
Project Amount: $397,304
RFA: Ecological Indicators (1999) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Aquatic Ecosystems
Description:Forested headwater streams comprise 60 75% of the total stream length and watershed area in the Mid-Atlantic states and are impacted by a variety of environmental stressors. Amphibians, in general, are considered to be valuable response indicators. In the Appalachian Region, a diverse assemblage of Plethodontid (lungless) salamanders thrive and reproduce in seeps, brooks, and small streams and can exist in extremely high densities. Unlike vemal pool breeding species, populations of most stream dwelling salamanders tend to be remarkably stable over time. Life histories within this group are highly variable and consist of aquatic and terrestrial egg-laying species with variable aquatic larval periods (8 months - 4.5 years). Previous studies indicate that early amphibian life stages (eggs, embryos, and recent hatchlings) are the most sensitive to low pH and metal toxicity. Interspecific differences in tolerance also exist within similar lifestages. If stream plethodontids show similar ontogenetic changes and interspecific differences, acidified or otherwise adverse stream conditions are likely to be important elements in shaping streambank salamander assemblages either through direct toxicity or indirect ecological interactions among community members. By virtue of their diverse and complex life histories, and abundant, stable, and geographically widespread populations, stream plethodontids offer the opportunity of providing another biological tool to assess headwater impairment and degradation, especially where traditional species assemblages (macroinvertebrates, fishes) are poorly developed or absent. A pilot project conducted in 1997-98 in 14 headwaters in the Allegheny Plateau, Pennsylvania, (Rocco and Brooks in prep) shows that stream salamander assemblages do respond to stream impairment. A dramatic response was documented in three species.
The objectives of this research are: 1) To describe the range and variability of stream plethodontid assemblage responses (SPAR) across commonly encountered gradients of anthropogenic degradation (stream acidification, forest and riparian corridor fragmentation and degradation, pollution, etc.) in the Mid-Atlantic Highlands Area (MAHA). 2) To develop and adjust SPAR for use in MA~ headwaters. 3) To evaluate the reliability and resolution of SPAR by application and verification.