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Bird - Lore 



the "importance of not relaxing for a 

 moment the campaign of extermination 

 that must be waged against the enemies 

 of wild life found within the borders of a 

 sanctuary." 



Under the head of 'Enemies of Wild 

 Birds' he returns to this same subject and 

 says: "We may never hope to increase the 

 numbers of our useful birds and quad- 

 rupeds until their natural enemies and 

 other distinctive agents are either largely 

 removed or reduced to a minimum." 



This statement is modified somewhat in 

 succeeding pages, but Mr. Scudder appar- 

 ently favors more interference with na- 

 ture's balance than Mr. Forbush advocates 

 (see succeeding review), if we would in 

 crease the numbers of song-birds about our 

 homes. Books of this kind cannot have 

 too large a circulation. — ^F. M. C. 



The Natural Enemies of Birds. By 

 Edward Howe Forbush, State Orni- 

 thologist. Economic Biology, Bull. No. 

 3, Mass. State Board of Agriculture, 

 Boston, 1916. 58 pages; 17 plates. 



Our attention has been so focused on 

 the unnatural enemies of birds that we 

 have given comparatively little thought 

 to their natural enemies. Mr. Forbush's 

 paper is therefore a welcome addition to the 

 valuable series on economic ornithology 

 for which we are already indebted to him. 



Under the head of 'Introduced Domesti- 

 cated Enemies' are included the cat, dog, 

 hog, grazing animals, and rat. To these 

 are added the following 'Feral Enemies': 

 Fox, mink, weasel, skunk, raccoon, red, 

 gray and flying squirrel, chipmunk, musk- 

 rat, meadow mouse, deer mouse, deer. 

 Shrikes, Crackles, Blue Jay, Crow, Hawks, 

 Owls, and Eagles, while some Culls, 

 Herons, Wrens and other species are 

 classed as 'Minor Bird Enemies.' 



'Introduced Bird Enemies' are the 

 English Sparrow, Starling, and Ring- 

 necked Pheasant and the list is completed 

 by the addition of the snapping turtle, 

 several species of snakes, frogs and fish 

 and, finally, various species of insects 

 which are said to be potentially the 

 greatest enemies of birds. 



Against this array of foes it might be 

 imagined that few birds would live to 

 reach maturity, but Mr. Forbush shows 

 how strictly natural enemies, and this 

 excludes introduced species, are necessary 

 to maintain that balance of life which 

 prevents any one species from having an 

 undue advantage over others and thus, in 

 time, overrunning the country in which it 

 lives. 



He does not approve, except under 

 certain special conditions, of attempting 

 to control the natural enemies of birds, 

 and he shows the futility of bounties. His 

 studies are summed up in the following 

 conclusions: "(i)Natural enemies of birds 

 are necessary and desirable, as they tend 

 to maintain within proper bounds the 

 numbers of the species on which they prey. 

 (2) Organized attempts to increase the 

 numbers of birds over large areas by des- 

 troying indiscriminately all natural en- 

 mies are undesirable. (3) Under certain 

 circurhstances enemies which have been 

 able to adapt themselves to man and his 

 works and have become unduly numerous 

 may require reduction in numbers. (4) 

 Individuals of useful species which may 

 become particularly destructive should be 

 eliminated. (5) Self-interest on the part 

 of the people most concerned eventually 

 will bring about such reduction of pred- 

 atory animals as is needed without the 

 stimulus of bounty laws, which in most 

 cases are pernicious and which, if enacted 

 at all, should be directed only against the 

 larger predatory animals or those which 

 are dangerous to human life or exceedingly 

 destructive to domestic animals or crops." 

 — F. M. C. 



An Index to Bird-Lore-VoIs. I — XV, 

 inclusive. Compiled by Ernest Inger- 

 SOLL. For sale by the National Asso- 

 ciation of Audubon Societies. Price, 

 50 cents. 



A glance through this useful work of 

 reference impresses one who has been 

 fairly familiar with the contents of Bird- 

 Lore, with the richness of the store of 

 information which is to be found in a set 

 of this magazine. Aside from the hundreds 



