This dataset supports: Hermann-Sorensen, H., Thometz, N.M., Woodie, K., Dennison-Gibby, S., and Reichmuth, C. In vivo measurements of lung volumes in ringed seals: insights from biomedical imaging. Journal of Experimental Biology. Marine mammals rely on oxygen stored in blood, muscle, and lungs to support breath-hold diving and foraging at sea. Here, we used biomedical imaging to examine lung oxygen stores and other key respiratory parameters in living ringed seals (Pusa hispida). Three-dimensional models created from...