Accession Number:

ADA291463

Title:

Effects of Starvation at Different Temperatures on Dry Tissue and Dry Shell Weights in the Zebra Mussel, Dreissena polymorpha (Pallas).

Descriptive Note:

Final rept.,

Corporate Author:

TEXAS UNIV AT ARLINGTON DEPT OF BIOLOGY

Personal Author(s):

Report Date:

1995-01-01

Pagination or Media Count:

23.0

Abstract:

Starvation effects on dry tissue and shell biomass were investigated in the zebra mussel, Dreissena polymorpha, at 5, 15, and 25 deg C. Subsamples of 30 individuals were examined daily for mortality. A second group was periodically randomly subsampled for dry tissue and shell weights. At 25 deg C, 100-percent mortality occurred after 166 days. No mortality occurred at 5 or 15 deg C after 229 days. Dry shell weight DSW was constant in mussels starved at 25 or 5 deg C, but increased significantly P 0.05 at 15 deg C, likely due to deposition of shell nacre in shells not increasing in length. Dry tissue weight DTW in starving mussels was significantly correlated with both shell length SL and days of starvation P 0.00001 and was significantly lower at higher test temperatures. Pre-starvation DTW of a 20-mm SL individual was 19.7 mg. DTW declined to 4.66 mg after 132 days at 25 deg C, and to 9.95 and 15.9 mg after 229 days at 15 and 5 deg C, respectively, corresponding to tissue biomass reductions of 73.8, 46.9, and 22.9 percent. DTW loss rates of 0.102, 0.043, and 0.021 mgday were recorded for standard mussels starving at 25, 15, and 5 deg C, respectively. As estimated from DTW loss rates, 02 consumption rates in starving standard mussels were 0.196 ul O2.mg-1 h at 25 deg C, 0.0837 ul O2.mg-1.h-1 at 15 deg C, and 0.0399 ul 02.mg-1 h-1 at 5 deg C, approximately 22.1, 13.5, and 8.5 percent, respectively, of O2 uptake rates recorded directly in nonstarved individuals. -BKA

Subject Categories:

  • Biology
  • Stress Physiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE