Chukchi Acoustic, Oceanographic, and Zooplankton (CHAOZ) Study 2011. The goals of this study were three-fold - Determine general presence and detailed movements of bowhead, fin, gray, and humpback whales in oil and gas lease areas using long-term passive acoustic recorder arrays, sonobuoys, shipboard visual observations, and opportunistic satellite tracking. 2. Monitor ecosystem change through the use of long-term biophysical moorings, shipboard observations and climate numerical models. 3. Assess the response of the whales to environmental changes (including climate and anthropogenic use of the area) by integrating the biophysical, passive acoustic, and large whale biology data sets. These findings will be useful for formulating designs of mitigation for human activities in the region. In particular, these data will be used to support National Environmental Policy Act analysis and documentation for Chukchi Lease Sales, Draft Proposed Programs, and monitoring, as well as ESA consultations, Marine Mammal Protection Act permitting, and preparation of Biological Evaluations and Biological Opinions. A SBE 49 was deployed synoptically with equipment used to sample icythoplankton and zooplankton at selected stations. Temperature and Conductivity were measured and Salinity and Sigma-T were derived from these measurements. While the SeaCAT measures values on the down and upcasts, only the upcasts are used.