Historical baselines and the future of shell calcification for a foundation species in a changing ocean
Abstract
Seawater pH and the availability of carbonate ions are decreasing due to anthropogenic carbon dioxide emissions, posing challenges for calcifying marine species. Marine mussels are of particular concern given their role as foundation species worldwide. Here, we document shell growth and calcification patterns in Mytilus californianus , the California mussel, over millennial and decadal scales. By comparing shell thickness across the largest modern shells, the largest mussels collected in the 1960sā1970s and shells from two Native American midden sites (ā¼1000ā2420 years BP), we found that modern shells are thinner overall, thinner per age category and thinner per unit length. Thus, the largest individuals of this species are calcifying less now than in the past. Comparisons of shell thickness in smaller individuals over the past 10ā40 years, however, do not show significant shell thinning. Given our sampling strategy, these results are unlikely to simply reflect within-site variability or preservation effects. Review of environmental and biotic drivers known to affect shell calcification suggests declining ocean pH as a likely explanation for the observed shell thinning. Further future decreases in shell thickness could have significant negative impacts on M. californianus survival and, in turn, negatively impact the species-rich complex that occupies mussel beds.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 15, 2016
- Source ID
- 10.1098/rspb.2016.0392
Entities
People
- Catherine A Pfister
- Eric Sanford
- J. Timothy Wootton
- Kaustuv Roy
- Robert T. Paine
- Sophie J McCoy
- Thomas H. Suchanek
Organizations
- Florida State University
- National Science Foundation
- United States Department of Defense
- University of California
- University of Chicago
- University of Washington