^'°1908^^'] Adams, Ecological Succession of Birds. 149 



influence must have some permanence and this may be sought in 

 the dynamic trend and dominant influences of different associa- 

 tions. It is difficult to conceive of other more rehable metliods of 

 approach to such jiroblenis. 



In addition to the scientific value of this line of investigation, 

 there are important economic applications of the laws of avian 

 environment. This is particularly true of forestry and agriculture. 

 The forestry problem is continually becoming more important, but 

 the relation of bird life to forests and forest succession has received 

 little attention. As agents for scattering seeds of trees and shrubs, 

 birds are very important. Here is where the interests of the avian 

 ecologist and forest ecologist overlap. The student of bird life 

 will wish to know how a region is to be reforested, and what suc- 

 cession of bird life will attend the succession of the forest as reforesta- 

 tion progresses. On the other hand, the forester will wish to know 

 how birds will aid or retard him in the process of reforestation. 

 Then, in guarding or protecting the forest, what help can be se- 

 cured from birds with regard to insect pests? These are only 

 samples to show that here is a field which, as time advances, will 

 become of more and more importance, and that these problems 

 will eventually call for specially trained men to handle them. 



In connection with forestry and agriculture we have quite ex- 

 ceptional conditions for extended experimental studies in bird 

 succession as related to forest succession, crop rotation, etc. The 

 relation of birds to agriculture appeals to a much larger number of 

 people than does their relation to forestry. There are several rea- 

 sons for this; first, because more persons are interested in farm and 

 horticultural crops than in forests; and second, because birds are 

 soon attracted in such large numbers by the food supply of grains 

 and fruits which these crops so greatly increase, that the extensive 

 destruction by birds readily attracts attention. And while we hear 

 much of the great reduction of certain species of birds in parts of 

 the country, it is not at all improbable that with the destruction of 

 the forests (which were dense and dominant and tended to limit the 

 abundance of many species frequenting the open), and the increase 

 of food in cultivated fields, there has been an increase in the total 

 number of birds, even in spite of the great numbers killed by man. 



But to the phase of succession with which we are primarily 



