340 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



LOCUSTELLA OCHOTENSIS (Middendorff) 



MIDDENDORFF'S GRASSHOPPER- WARBLER 



Contributed by Winsob Marrett Tyler and Bernard William Tucker 



HABITS 



Middendorff's grasshopper-warbler is a little bird belonging to the 

 Old World subfamily Sylviinae. It winters in the Malay Archipelago 

 and moves northward, by way of Japan, to its breeding grounds on 

 the Kuril Islands, Kamchatka, and the eastern coast of Siberia. 

 La Touche (1926) gives the bird's range in more detail, stating: 



Middendorff's Grasshopper- Warbler appears to pass in numbers at Shaweishan 

 on its way to and from Japan and extreme North-East Asia. Dr. Hartert gives 

 Kamtschatka, the Siberian coast of the Sea of Ochotsk, and "Schantar-Island," 

 Kurile Islands, as the breeding range; also Behring Island. It winters in the 

 Malay Archipelago. This bird has not often been taken on the mainland of 

 China. I obtained it in the reed-beds and by the river-banks at the mouth of the 

 River Min (Fohkien Coast) at the end of May and beginning of June, and have 

 specimens from East Fohkien dated September and October. * * * There 

 is no record of the bird having been taken in North China, and it doubtless 

 migrates via Japan and Corea. 



The occurrence of Middendorff's grasshopper-warbler as a North 

 American species was established by a single specimen secured on 

 September 15, 1927, on Nunivak Island, Alaska, an island to the 

 north of the Aleutian Chain. Of this individual Harry S. Swarth 

 (1928) says: "One specimen: C. A. S. No. 30760, female, bird-of-the- 

 year, September 15. The range of Middendorff's Grasshopper- 

 warbler includes the north-eastern coast of Siberia and the Kurile 

 Islands, so that its occurrence in Alaska is no more extraordinary than 

 that of some other Asiatic birds that regularly cross Behring Sea. 

 The capture of this bird adds to our Check-List a species and genus in 

 the family Sylviidae." 



Swarth (1934) describes the specimen thus: "Bill, upper mandible 

 brown, lower mandible brownish orange at base, shading through 

 brownish yellow to a dusky tip; iris brown; tarsus purplish brown, 

 toes rather pale brown." 



The species is treated binomially in the A. O. U. Check-list, but 

 two races are now generally recognized, L. ochotensis ochotensis, of 

 Kamchatka, the Commander and Kurile Islands, Sakhalin, and the 

 coasts of the Sea of Okhotsk, and L. o. pleskei Taczanowski, of Korea 

 and some of the Japanese islands. The latter is a somewhat larger 

 bird with a longer bill, the culmen, according to Hartert and Stein- 

 bacher (1938), measuring 18.5-22 millimeters as against 15.5-17 

 millimeters in the typical race. Yamashina (1931) gives the corres- 

 ponding figures as 16.5-17.5 millimeters (17 specimens) and 14-16.5 

 millimeters (53 specimens). There are also some color differences 



