Greeting All, I am a member of a consortium that is studying population size and structure of Tursiops truncatus along the east coast of Florida. My task is to determine the optimal way to record and measure variable survey effort for a huge study area (600+ km by 40+ km). Here is what I know so far: 1. Designate strip transects and only record it if the transect was complete. This way you know the exact water covered and how often—problem “loose” data from incomplete survey days. 2. Divide a survey area into 1 km zones and record each zone completely covered during each survey. Then the measure of effort would be how many times that zone was covered—problem cumbersome when the survey area is huge (600 km by 20 km or so) 3. Use a GPS to record a trackline and enter it into a DB….that’s all I know about this method since I’m behind in the technological times and would like to know more about this technique! Any advice, comments, opinions, or alternative methods would be GREATLY appreciated. I will compile a summary of your responses and post it to the list so that others my benefit from this query. Thank you in advance for your help, Marthajane ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Marthajane Caldwell, Ph.D., Marine Mammal Behavioral Ecology Studies, Inc. 8429 Cresthill Avenue Savannah, GA 31406 marthajane_c@yahoo.com 912-655-1765 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~