^ook Ji^ehjsi anb lEtebietris; 



The Red-winged Blackbird. A Study 

 in the Ecology of a Cat-tail Marsh. By 

 Arthur A. Allen, Zoological Labora- 

 tory, Cornell University. Abstract 

 Proc. Linn. Soc. N. Y. [care of Am. 

 Mus. Nat. Hist.] Nos. 24, 25, 1914, pp. 

 43-128; pis. 20; figs. 2. 



In this admirable monograph Dr. Allen 

 has not only given us much new informa- 

 tion concerning the habits of the Red- 

 winged Blackbird, but also a demonstra- 

 tion of methods in the study of birds 

 in nature which forms an object lesson 

 we cannot too strongly commend to the 

 field student. 



Bird-Lore has long advocated spe- 

 cialization as a means of extending the 

 boundaries of the known and of deepening 

 one's interests. Here then, is a model 

 which, we gladly confess, represents a 

 distinct advance over anything we had 

 in mind. 



Ornithologists have been too prone to 

 flock by themseVes. Their studies have 

 been apt to consider the bird apart from 

 its environment — as that term implies 

 not alone climatic and physiographic 

 factors, but all the other forms of life 

 with which directly or indirectly it may 

 come in contact. While such studies 

 may be above criticism by ornithologists, 

 they are far from filling the demands of 

 the ecologist. That is, of one who studies 

 the relationships of organisms to one 

 another and to their surroundings. 



Dr. Allen's paper is a contribution to 

 this newer, broader type of ornithology. 

 It opens with a study of environment. 

 The "plant associations" with their char- 

 acteristic animals are outlined, and the 

 changes due to seasonal or other causes 

 mentioned. 



This generalized survey of a particular 

 area lays the foundation for the more 

 specialized study of any of the forms of 

 life which inhabit it, whether plant, fish, 

 reptile, bird, or mammal. From its fauna 

 Dr. Allen selects as his subject the Red- 

 winged Blackbird, and Part II of his 



(2 



paper (pp. 74-128) is devoted to an eco- 

 logical study of this bird as it was 

 observed in and near Renwick Marsh at 

 the head of Cayuga Lake, New York. 



Beginning with the Redwing's migra- 

 tion, some conception of the intensiveness 

 of Dr. Allen's studies may be gained by 

 the following table. Doubtless few birds 

 have been more generally recorded in 

 migration than this conspicuous species, 

 but where else will we find such detailed, 

 intimate information in regard to its 

 movements? 



I. Vagrants. Feb. 25, March 4. 



II. Migrant adult males. March 13- 

 April 21. 



III. Resident adult males. March 25- 

 April 10. 



IV. Migrant females and immature 

 males. March 29-April 24. 



V. Resident adult females. April 10- 

 May I. 



VI. Resident immature males. May 

 6-June I (1910). 



VII. Resident immature females. May 

 lo-June II (1910). 



With these dates is presented much 

 correlative matter in regard to the develop- 

 ment of vegetation, changes in food-sup- 

 ply, variations in actions, sexual growth, 

 etc., all of which is designed to show the 

 relation of cause and eflEect. Consequently, 

 we have a contribution not alone to 

 ornithology but to general biology — or 

 better, to bionomics. 



'Mating and Song,' 'Nesting,' 'The 

 Young,' 'Fall Migration,' 'Enemies,' 'Molt 

 and Plumage,' 'Food and Food-supply,' 

 'Correlations Between Changes of Food 

 and Changes in Structure of Stomach,' 

 'Correlations in the Changes Occurring in 

 the Reproductive Organs,' are the further 

 headings under which Dr. Allen presents 

 the results of his studies of the Redwing. 

 Each contains something more or less 

 original in matter and in method; and 

 each contributes to what, in our opinion, 

 is the best, most significant biography 



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