In this math lesson, learners apply the concepts of ratio and proportion to the capture-recapture statistical procedure. Learners are given containers (the bay) and an unknown number of fish-shaped cheese crackers to use in simulating the capture-recapture method. Learners net the fish-shaped cheese crackers and substitute fish-shaped pretzels to simulate tagged fish. Learners then take samples and record the number of tagged fish and the total number of fish. After several samples are taken, results from each group are recorded. Learners apply their knowledge of proportion to arrive at the total fish population. This activity relates to the decline in fish populations in the Chesapeake Bay.