Meeting Abstract
P2.9 Saturday, Jan. 5 Sub-lethal impacts of ocean acidification and elevated temperature on two molluscs from the western Antarctic Peninsula SCHRAM, J.B.*; SCHOENROCK, K.M.; MCCLINTOCK, J.B.; AMSLER, C.D.; AMSLER, M.O.; ANGUS, R.A.; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham jbschram@uab.edu
Current changes in anthropogenic atmospheric carbon dioxide concentrations are increasing at unprecedented rates and altering ocean carbonate chemistry (ocean acidification). Coupled with rapidly rising sea surface temperatures along the western Antarctic Peninsula, this region of the Southern Ocean is projected to be undersaturated with respect to calcite and aragonite before warm water environments, thus putting additional abiotic stress on calcifying marine organisms. The present study examines the sub-lethal effects of decreased seawater pH and increased temperature on buoyant and wet weight as well as righting responses in the common Antarctic limpet Nacella concinna and mesogastropod Margarella antarctica. Experimental animals were collected by hand using SCUBA within 3.5 km of Palmer Station, on Anvers Island off the central western Antarctic Peninsula. We selected two pH levels (pH 8.0, 7.6) and two temperatures (1.5oC, 3.5oC) to measure sub-lethal impacts in both species over a 43-day period. The pH levels selected represent current mean ambient seawater conditions in the vicinity of Palmer Station, Antarctica (pH 8.0, 1.5oC) and a pH predicted to occur by year 2100 (pH 7.6, 3.5oC). Following analysis, we found no significant changes in wet or buoyant weights over the experimental period. There also were no pH-temperature mediated differences in the proportion of N. concinna to right in 24-hours or the time to right for M. antarctica. This common molluscan macrograzer (N. concinna) and mesograzer (M. antarctica) appear to be resistant to a 43-day exposure to conditions predicted for the western Antarctic Peninsula.
