⚖️ Weight Management Math · 7 min
Rations and food quality
Why this matters
You control weight through the ration, and the ration has two dimensions: how much, and what. The manual is emphatic that the second one is not a detail.
By the end of this lesson you will be able to
- Size a daily ration as a percentage of body weight
- Adjust a ration for the caloric density of the food
- Calculate how far a given ration will move a bird's weight
Ration as a percentage
Daily rations for a working falconry bird commonly run somewhere around 5 to 10% of body weight, higher in hard cold, when flying hard, when growing, or when recovering. As with everything else here, the percentage is the useful unit.
A 1,150 g red-tail on a 6% ration: 1,150 × 0.06 = 69 g of food, which is about 2.4 ounces.
Then adjust for the food
Here is the manual's key point restated as arithmetic. Dark, rich meats carry substantially more energy per gram than pale meats. The manual's own example: a bird that maintains on 2 oz of whole pigeon per day will lose weight on 2 oz of rabbit. Same mass, less energy.
| Richer, feed less | Leaner, feed more for the same effect |
|---|---|
| Duck, large mammal meat, pigeon (with its disease caveats) | Rabbit, young domestic chicken, pheasant, upland game bird |
So a ration is never just a number of grams. Two ounces is a meaningless instruction until you say two ounces of what.
Washed meat
Meat soaked in cold water is used deliberately to lower a bird's weight or to increase hydration: you are feeding volume with much of the nutrition rinsed out. It is the tool for bringing a bird down without cutting the quantity it eats, which keeps the bird occupied and the crop working.
Moving a weight on purpose
Your red-tail is at 1,200 g and you want her at 1,150 g. She holds steady on 70 g of rat per day. Cutting to 55 g creates a deficit; how fast the bird responds depends on the individual, the weather and the exercise, which is why you change one thing and then read the scale for two or three days rather than chasing the number daily.
Never chase a number in one jump
A bird's weight and condition respond to food type, food quality, temperature, disease, season, barometric pressure, exercise, species and individual metabolism. Cut hard on the basis of one morning's reading and you are correcting for a cold night, not for a fat bird.
This lesson is part of the NY Falconry Exam course. Open it in the course to answer the retrieval checks that go with it, track what you have read, and quiz the whole unit. Lessons, quizzes and the glossary are free.