Studies of Heat Tolerance of Zebra Mussels: Effects of Temperature Acclimation and Chronic Exposure to Lethal Temperatures.
Abstract
Chronic (i.e., long-term incipient) upper lethal temperatures were determined for zebra mussels (Dreissena polymorpha) acclimated to 5, 10, 15, 20, 25, or 30 degress C for at least 14 days. Subsamples (n=25-33) from each acclimation group were exposed to constant temperatures of 31, 32,33, 34, 35, 36, or 37 degrees C (+ or - 0.1 C). Mussels were brought from acclimation temperature to test temperature by increasing media temperature at a rate of 1 C/10 min. After reaching the test temperature, mortality was determined every 15 min for the first 2 hr, every 30 min for the next 3 to 5 hr, and every hr for the next 17 to 21 hr and every 3 to 4 hr thereafter until all individuals had died. Multiple regression analysis indicated that acclimation temperature, exposure temperature, and mussel shell length (SL) were significantly correlated (P<0.00001) with the natural log of thermal tolerance time. Tolerance time increased with increasing acclimation temperature and decreasing SL and decreased with increased exposure temperature. LT(50) values (i.e., estimated time for 50-percent sample mortality) ranged from 1 hr at 37 degrees C regardless of acclimation temperature to 456 hr in 25 degrees C-acclimated individuals at 31 degree C. (AN)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1995
- Accession Number
- ADA293200
Entities
People
- Michael F Clarke
- Milton A. Matthews
- R. Chase
- Robert F. Mcmahon
- Thomas A. Ussery
Organizations
- University of Texas at Arlington