290 GROUSE AND OTHER LAND BIRDS 



the willows are destroyed by the breaking of the 

 tips and the buds, and the shrub takes about two 

 years to recover, which is generally by fresh 

 sprouts from the root. As the food fails the birds 

 have to move elsewhere. It would, therefore, ap- 

 pear from my data that it takes about ten years to 

 go round their circle of migration. I say circle 

 because their line of flight seems to indicate this. 

 They first appear on the Labrador coast line fly- 

 ing south and continue so till they reach our large 

 rivers like the Manicouagan, Bersimis and the 

 Saguenay, seldom going west of this last. These 

 large rivers are followed up in a west and north- 

 westerly direction, the birds scattering inland 

 over a tract that includes the Lake St. John and 

 Lake Mistassini region, then down to the shores 

 of Hudson's Bay, where Dr. Milne and Mr. Peter 

 McKenzie told me they flew north all along the 

 coast line to Ungava, then south again to the Lab- 

 rador, and so on. The range of the flight on this 

 side of Hudson's Bay would cover about ten de- 

 grees of latitude and in round figures form a cir- 

 cle around this big peninsula, of about two thou- 

 sand miles. As this immense body of ptarmigan 

 moves on during a season of abundance, stragglers 

 are left behind, which breed, giving another and 

 lesser batch to migrate the second year, when 

 fewer stragglers are left, till the third or fourth 

 season, when no more are seen for a time. Their 

 total absence varies from four to six years. They 



