abstracts: ornithology 603 



ORNITHOLOGY.— A list of the birds observed in Clay and O'Brien 

 counties, Iowa. Ira N. Gabrielson. Proc. Iowa Acad. Sci. 24: 

 259-272. 1918. 

 Clay and O'Brien counties lie in northwestern Iowa in the prairie 

 region near the Great Plains. The country is nearly all rolling prairie 

 now largely under cultivation, and the only timber consists of the 

 fringes along the streams and about some of the lakes, together with 

 the trees planted about buildings. The artificial groves have exerted 

 an important influence in attracting numbers of birds that favor the 

 vicinity of hmnan habitations, and have decidedly increased their 

 numbers. Another important result of the settling up of this part of 

 Iowa is the draining of innumerable ponds and marshes that formerh'- 

 existed in the prairie regions. This has brought about a great change 

 in the breeding water-fowl population, for these birds have practically 

 disappeared from the area. The present list comprises 136 species, of 

 which forty-seven are water birds and shore birds. The latter are 

 particularly interesting as showing what species of water-fowl lived in 

 this region before the elimination of their favorite breeding places. 



Harry C. Oberholser. 



ORNITHOLOGY.— .4 second bird survey at Washington, D. C. Harry 

 C. Oberholser. Wilson Bulletin 30: 34-48. 1918. 

 The scientific results of our first comprehensive bird census ilear 

 Washington, D. C, were so important that we decided to repeat it in 

 the spring of 1917. On this second occasion twenty-two naturalists 

 took part, and the seventeen parties covered the various kinds of 

 country within twenty miles of the city. The date chosen was May 11, 

 1917, one day earlier in the month than in 1913. An extraordinarj- 

 combination of circumstances made this time exceptionally favorable 

 for birds; and the results were as remarkable as they were interesting. 

 The total number of species observed by all the parties collectively 

 was 166, which is, so far as we are aware, the largest number ever 

 reported in a single day at any locality in the United States. The 

 total number of individual birds noted was 17,074. The reasons for 

 this rather astonishing result are not far to seek. The very cool 

 weather of April and early yiay induced the winter residents to remain 

 late, and at the same time retarded the movements of the later mi- 

 grants; so that while a large number of species was present, there were 

 only a few individuals of many of the more tardy migrants on this 

 May 11, on which date the spring migration about Washington is 



