Konyukhov and Kitaysky 



Chapter 2 



The Asian Race of the Marbled Murrelet 



Young Birds 



It is not clear how nestlings depart from the nest. As in- 

 dicated earlier, nests can be situated close to or on the ground 

 making it difficult for the young to take off. Some investigators 

 believe that the young could use the nearest river or stream 

 to reach the sea (Kistchinsky 1968a, Kuzyakin 1963). 



There have been no descriptions of murrelet chicks in 

 Asia. Young birds were found in late July 1976 on the fresh 

 water Ozhabachye Lake on the Kamchatka Peninsula (Vyatkin 

 1981), in Mordvinov Bay, Sakhalin Island, on 6 August 

 1972 (Nechaev 1986), and in South Kuril Strait, Kunashir 

 Island. on 8 August 1963 (Nechaev 1969). Two young birds 

 were taken in Avacha Bay, Kamchatka Peninsula, on 9 and 

 18 August 1920 (Lobkov 1986). There are two skins of 

 young birds in the Zoological Museum in St. Petersburg. 

 These were taken from the Kamchatka Peninsula in the 

 middle of August 1 889 and in Aniva Bay, Sakhalin Island, 

 on 23 September 1947. Four fledged young were collected 

 close offshore near the foot of Mt. Mokoto, Hokkaido, in 

 late August of 1982 (Brazil 1991). 



Foraging 



During the breeding period, the distribution of foraging 

 Marbled Murrelets is linked to the estuarine ecosystems. 

 They usually forage singly or in pairs, and rarely in groups 

 of up to eight individuals. Near the southwest coast of the 

 Sea of Okhotsk, birds fed from between 200-300 m to 

 approximately 2-3 km offshore (Babenko and Poyarkov 

 1987). In Amur Lagoon they fed up to 5-10 km from the 

 shore in brackish water (Shibaev 1990), the depth of which 

 is 1-10 m. In the Kamchatka Peninsula, birds congregate in 

 bays, especially large ones (Lobkov 1986, Vyatkin 1981). 

 Near the Kuril Islands, they have been observed opposite 

 sandy beaches, very close to the shore (Velizhanin 1977). 

 During observations in Tauy Liman area (in low-salinity 

 water), birds foraged in shallow (5-20 m) inshore waters 

 (Kitaysky. unpubl. data). 



In addition to feeding at sea, murrelets forage in large 

 freshwater lakes on the Kamchatka Peninsula. On Sakhalin 

 Island, murrelets were found regularly on two brackish 

 lagoons. Kronotzkoe Lake (20-30 pairs) and Kurilskoe Lake 

 (15-20 pairs) (Lobkov 1986, Nechaev 1986). 



Only the remains of invertebrates were detected in the 

 stomachs of birds collected in late June (the beginning of the 

 breeding season) (Yakhontov 1979). Adult birds feed their 

 chicks on fish (Kistchinsky 1968b, Shibaev 1990), though 

 the exact composition of the diet is not known. We have 

 observed birds feeding on both capelin (Mallotus villosus) 

 and sand lance (Ammodytes hexapterus) in the northern Sea 

 of Okhotsk. 



There are no direct reports on the availability of food 

 resources, but according to indirect sources, they are 

 ephemeral. For instance, near Baydukov Island, birds were 

 absent on 26 July 1985, although during the previous day 

 their density there was about 10 birds per kilometer of travel 



along the transect route (Babenko and Poyarkov 1987). High 

 densities of murrelets in these areas are probably connected 

 with aggregations of small fish, which are related to the 

 complex dynamics of the oceanography in estuarine systems. 



Migration 



There is no information on visible observations of this 

 murrelet' s migration along the coastline. Birds disappear 

 from the breeding range along the Kamchatka Peninsula in 

 September (Lobkov 1986). In Ekaterina Bay, where they 

 were common in summer, murrelets were gone by the end of 

 October (Babenko and Poyarkov 1987). It is possible that a 

 small number of birds reside in winter off Sakhalin Island 

 (Nechaev 1986), but most of them migrate south to Japan 

 (Brazil 1991, Shibaev 1990). It is possible that the species 

 also winters in Alaskan waters based on a specimen (ZMZI 

 5033) taken on or near Kodiak Island in January 1845. It is 

 more likely, however, that this bird was a vagrant. At least 

 13 specimens of this race of the Marbled Murrelet have been 

 collected at various inland locations in North America in 

 recent years (Sealy and others 1982, 1991). 



Molt 



We have little information on the molt of the Asian race 

 of the Marbled Murrelet. According to data taken from 

 collected birds, primary and rectrix molt of adults takes 

 place between late July, when all birds have old feathers, 

 and late October, when birds are in new plumage. Some 

 birds, taken in early September from Avacha Bay, Kamchatka 

 Peninsula, had begun their primary molt, but others had not. 



According to Koslova (1957), "A complete fall molt 

 starts in cases with some adult murrelets in the first week of 

 August. A female collected on 7 August in the Northern part 

 of the Tatarskiy (Tartar) Strait (Taba Bay) had fresh feathers 

 on the belly. Primaries, secondaries and tail feathers had not 

 changed. Another female collected on 3 1 August in the Sea 

 of Okhotsk had all its primaries, secondaries, and tail feathers 

 fall out and the small feathers in the lower side were still in 

 the tube [sheath] phase. Other adult individuals are delaying 

 molt and have the full breeding plumage on the last week of 

 August (date of collection: 18 August from the Litke Strait 

 and on 24 August from the Ayan) without any signs of molt". 



The sequence of molt is variable, and birds do not lose 

 all their primaries at once. They can possibly fly during 

 early stages of primary molt. The primary molt begins from 

 the inner end of the primaries. It is likely that greater coverts 

 of the primaries are lost earlier than the primaries themselves. 

 Specimens show a variable amount of loss of flight feathers 

 during molt. Individual specimens have lost between three 

 (ZMZI 15993 1/425-974) and ten old primaries (ZMZI 159933/ 

 425-974) during molt. On the other hand, there was a specimen 

 taken in the Sea of Okhotsk on 19 August 1845 which had 

 lost all its primaries and secondaries (ZMZI 5047), and was 

 obviously flightless. 



USDA Forest Service Gen. Tech. Rep. PSW-152. 1995. 



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