_Feather Eating or "Quilling"._ This is a bad habit which is apt to cause more or less trouble when the ducklings are about two-thirds grown. It is much more likely to occur when the birds are kept in cramped quarters. It is usually started by one or a few individuals but when the feathers are injured so that they begin to bleed, which they will very quickly do, the vice will spread among the whole flock and serious damage will occur. It is therefore necessary to be on the lookout for this trouble, and as soon as detected, the birds responsible should be removed. If the culprits are placed with older birds which are already feathered, they will not trouble by trying to eat the feathers. It is the blood in the growing feathers which attracts them. If the habit has become general, it is more difficult to check. About the best thing that can be done, is to turn them out in a roomy yard, one with a growing green crop, if available, where they will be so busy as to stop the feather eating of their own accord. _Rats._--Rats are very destructive if they get into the brooder house. A single rat has been known to kill and drag off as many as 200 ducklings in one night. If a rat gets into the brooder house it is therefore of the utmost importance that it be hunted down and killed without delay. Otherwise serious losses will result. Cooperative Feed Association A very large proportion of the feed used on a duck plant is that which is fed to the market ducks. By purchasing feed in considerable quantities the duck grower is able to cut down the cost to some extent. A number of the duck raisers on Long Island have developed this idea further by forming a cooperative feed organization. Stock in this concern is held both by the duck growers and by outsiders but is controlled by the duck growers. The feed association maintains a feed warehouse, purchases feeds in quantity and does business both with the duck growers and with other persons in the market for feed. The existence of a cooperative feed purchasing association of this sort not only cuts down to some extent the cost of feed but likewise makes it possible for the duck growers to have greater assurance of securing the supply which is so necessary to them during the growing season. CHAPTER VII Commercial Duck Farming--Marketing On commercial duck farms, the business consists mainly of producing large quickly grown ducklings which are marketed before they are mature. Because of this immaturity, the ducks are quite commonly termed green ducks. The business has also become so highly specialized on Long Island and this is such a center of the industry, that the birds are commonly quoted on the New York market as Long Island ducklings.