CARRYING CAPACITY OF RICEFIELDS FOR MALLARDS

1. Mallards must consume 2/10 of a pound or 3.2 ounces of rice per day on the average just to sustain a health/life. (2/10=x/16= 3.2)*
   
   
2. At this rate just to sustain health/life, it takes 5 mallards to consume one pound of rice per day. (16/3.2=5)
   
   
3. There are 45 pounds of rice in a bushel.
   
   
4. It therefore takes 210 mallards to eat one bushel of rice per day. (45x5=210)
   
   
5. Average yields of rice per acre at Bald Knob NWR by previous farmer was 110 bu./ac. Therefore it takes 23,100 ducks to eat an acre per day. (110 bu/ac x 210 mallards/bu = 23,100 mallards)
   
   
6. Therefore, it would take 2,310,000 mallards to consume 100 acres of rice per day. (23,100 x 100 acres = 2,310,000)
   
   
   1. How long then would it take for a concentration of 100,000 mallards to consume 100 acres of rice? Answer: 23.1 days (2,310,000 / 100,000 = 23.1)
      
      
   2. How long would it take for a concentration of 150,000 mallards to consume 100 acres of rice? Answer: 15.4 days (2,310,000 / 150,000 = 15.4)
      
      
   3. Same question by 200,000 mallards? Answer 11.5 days
      
      
   4. Same question by 250,000 mallards? Answer 9.2 days
      
      
   5. Same question by 400,000 mallards? Answer 5.7 days
      
      
   6. Same question by 600,000 mallards? Answer 3.8 days

* Source: Personal communication with Dr. Kenneth J. Reinecke, USGS, Patuxent Wildlife Research Center