I'm assuming you left off "person" behind "average." The US Dept. Of Agriculture estimates that the average person in the United States eats .5 lbs of meat, 1.6 lbs of dairy products, .2 lbs of fats...
This depends on the species of otter, generally speaking otters have a high metabolic rate and require large amounts of food to generate body heat, river otters eat 15% to 20% of their body weight...