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economic importance than are all the native birds combined. 

 rSince there is bnt little to be expected from the native avi- 

 fauna along the line of insect control, what is required is the 

 judicious introduction of foreign birds to feed on our insect 

 pests. We could thus form a second line of defense against 

 insect invasions that will be a first aid to the plant and animal 

 quarantine now maintained here by the territory and nation. 



The intelligent introduction of birds into Hawaii or any 

 other country is by no means the simple task that some have 

 thought it to be. Three important questions with reference to 

 their food habits must be settled definitely in advance of the 

 liberation of any species of bird in' the Territory. They are: 

 (1) The food of the species at home. (2) What proportion of 

 its food is injurious insects? (3) What its food will be when 

 brought to Hawaii ? 



On the mainland the conditions existing about a farm home 

 are far different from those found in Hawaii. There the yard, 

 garden, orchard, meadow, field crops, shrubs and forest have 

 their special bird inhabitants. In case of an insect outbreak 

 they all take part in suppressing the invasion. The average 

 farm on the mainland during the year has more species of birds 

 than occupy the entire land area of the Hawaiian group. It 

 has been found, however, that not all birds are good birds at 

 all times. Most of them, however, are so useful on the average 

 as to warrant their general protection. 



The development of the study of economic ornithology is 

 still in its infancy. Wilson, in 1808, won the title of being the 

 pioneer in America. Audubon, like Wilson, spoke in general 

 terms of the habits and value of birds. Their direct benefit to 

 agriculture was first appreciated in 1850, and Flagg in 1861, 

 in a paper on the '^Utility of Birds," declared that ''each species 

 performs certain services in the economy of nature which can- 

 not be so well performed by other species." Prof. Jenks devised 

 the system of alimentary analysis which has been much used in 

 the study of the habits of birds. The Biological Survey was 

 first organized in 1885, and from first to last 300 or more 

 papers have appeared of more or less value. These form the 

 bulk of the economic literature on I^orth American birds. Very 

 little of the work done on the mainland, however, is of direct 

 use in considering the problems of Hawaii, for the obvious 

 reason that her problems are her own and very peculiar to 

 the gToup. 



