trafton] students TO TEACH ABOUT BIRDS 87 



V. Economic Value of Birds. 



A. Value of adult birds. (From food chart) 



B. Value of nestlings. (From data furnished) 



The students are taught how to find the name of unknown birds 

 by use of the key and colored pictures. Some of the points in the 

 first outline are answered from a study of bird skins and some from 

 the chart of Minn, birds. For determining the economic status of 

 each bird, the members of the class are furnished with a food 

 chart of our common birds based on the reports of the Bureau of 

 Biological Survey. The facts regarding their food habits are 

 arranged under the following headings: 



To Bird's Credit To Bird's Discredit. 



Insect Mammal Weed Total Grain Fruit Poultry Total 

 pests pests seeds credit discredit 



The data are given in percent of the total food. 



At the close of the laboratory studies a test is given on the 

 number of birds which the students can identify. 



During the Spring and Summer terms special attention is 

 given to the field work. Preceding these trips laboratory studies 

 are made of the birds in the order of their arrival in the spring, 

 as previously explained. The purpose of the field trips is two-fold; 

 to identify the birds in the field, and to make some study of the 

 activities of birds. A field glass is furnished for each three or four 

 students. Arrangements are usually made so that most of these 

 trips are taken in the early morning or late afternoon. 



The following directions are given the students to guide their 

 observations. 



Purpose : To study birds so as to be able to name them and to 

 appreciate some of their interesting habits. 



For each bird studied record observations regarding the follow- 

 ing points. Copy in your notebook the complete outline for each 

 bird, and if all the points are not observed on one trip, fill them in 

 at some later trip. 



I. Points to aid in identification. 



1. Size. (Compare with robin or English sparrow.) 



2. Chief color markings and their location. 



3. Method of flight. 



4. Other noticeable features. 



