Dr. Grothues is interested in the abundance and distribution of fishes as responses to physical factors. These responses include those that could be considered involuntary, such as distribution of larvae by ocean currents and mortality or loss of reproductive capacity in unsuitable environments, and voluntary behavioral responses, such as migration, ranging, and sheltering (including burial). The physical forces that he investigates as impacts include natural and anthropogenic perturbations such as restoration efforts, urbanization of water fronts, seasonal and inter-annual water quality fluctuations and ocean structure. In the last 10 years Thomas has worked extensively with adult stages on movement, migration, and habitat choice. In doing so, he developed an interest in furthering technologies and strategies to meet the challenges of studying highly mobile fish in the ocean, including sablefish in deep Alaskan waters, sturgeon, flounder, and other sport fishes along the East and Gulf coasts of the US, and pelagic thresher sharks in the Visayan Sea. The development of tools such as payload-controlled autonomous underwater vehicles for fish tracking and imaging, and related processing algorithms for sonar image classification and decision making, can be revealing but require understanding of natural history and behavior in order to be effective in implementation. Theses investigations are therefore truly cross-disciplinary and involve collaborations with other biologists, phyisical and geological oceanographers, commercial fishers, and mechanical, electrical, computer, and acoustical engineers, as well as interaction with Federal, State, municipal, and private-sector resource managers.