26 IDENTIFICATION OF A SPECIMEN IN HAND 



IDENTIFICATION OF A DUCK 



Put in its simplest form, the specimen which the gunner will want 

 to identify in the autumn may be any one of: 



(a) An adult male in eclipse plumage, during its autumn moult, 

 or in its full winter plumage. 



(b) An adult female in its full winter plumage, or emerging from 

 its slightly modified summer plumage. 



(c) A young male of the year in its juvenile plumage, during its 

 autumn moult, or in its first winter plumage. 



(d) A young female of the year in its juvenile plumage, during its 

 autumn moult, or in its first winter plumage. 



One should endeavor to become proficient in noting all signs of 

 maturity, immaturity, and sex. In the section "Sex and Age Determina- 

 tion" which follows this section on Identification, several methods for 

 establishing sex and age are given. The word "age" is used to differen- 

 tiate between an adult bird and an immature one. Of the methods listed, 

 the Cloacal Method is the most exact means of establishing sex and age, 

 though the others must not be ignored as in many cases they will suffice 

 for the purpose of quick identification. In many instances it will greatly 

 aid in the identification of the species if the age and sex of the specimen 

 are determined before proceeding with the identification. 



In the identification of a specimen it is wise to proceed in an orderly 

 manner. Two definite steps are necessary; the two simple "Keys" set 

 out below will assist in identification by the quickest and surest route. 

 The first key employs the structure of the hind toe; the second key is 

 based on the wing pattern. Much time will be saved, and much flounder- 

 ing will be avoided by the use of these keys as suggested. 



Read this section carefully. After a few experiments, the procedure 

 of identification will become automatic. 



THE FIRST STEP 



The first step in identification is to place the bird in its proper sub- 

 family. This is quickly accomplished by the "hind-toe formula" which 

 provides a key to the subfamily. 



KEY TO THE SUBFAMILY 



(1) Hind toe without lobe (fig. 7, page 5) 



(a) Legs short; feet do not extend well beyond tip of tail 

 ONE OF THE RIVER AND POND DUCKS 



(b) Legs long; feet extend well beyond tip of tail 

 ONE OF THE TREE DUCKS 



(2) Hind toe with lobe (fig. 9, page 6) 



(a) Bill broad; never cylindrical or "toothed" 



ONE OF THE DIVING DUCKS (OR A RUDDY OR MASKED DUCK) 



(b) Bill narrow, cylindrical, and with conspicuous "teeth" 

 ONE OF THE MERGANSERS 



