NON-INDIGENOUS BRITISH BIRDS. 147 



the only species with which they are Hkely to be 

 confused — by their smaller size (either in length or 

 breadth or both) and lighter shell weight. They are 

 also perceptibly whiter. 



Family ANATID/E. Genus Chen. 



Sub-family ANSERIN.E. 



LESSER SNOW GOOSE. 



Chen hyperboreus {Fallas). 



(British : Very rare abnormal autumn migrant.) 



Single Brooded. Laying season, June. 



Breeding area : Apparently North-western Nearctic 

 region, and probably extreme North-eastern Palsearctic 

 region. The Lesser Snow Goose is only known to breed 

 in the north-west of Arctic America (Esquimaux Lake, 

 Liverpool Bay, etc.), in Alaska, and possibly on the 

 tundras of the Tchuski Land in North-eastern Siberia, 

 and the islands off that coast, as the bird was met with 

 by Pallas in that area. 



Breeding habits : The Lesser Snow Goose reaches 

 its breeding grounds towards the end of May or early 

 in June. It migrates in flocks, but whether it is gre- 

 garious during the breeding season is not known. It 

 is probably to a certain extent social during this period, 

 and seems to pair for life. Only the most meagre 

 details have been recorded of this bird's habits during 

 the season of reproduction. Nests found on an island 

 near the mouth of the Anderson river, are described 

 by MacFarlane as mere hollows in the sandy ground 

 warmly lined with down, but he does not appear to have 

 seen them in situ. 



