ALASKA LONGSPUR 1617 



blotching of reddish brown, principally at the large end, some with 

 a fine reddish brown specking, and others with varying types and 

 intensities of marking including spots, spots and blotches, and irregular 

 zigzag markings of dark umber brown. The markings become 

 heavier and darker colored (chocolate brown) until the ground color 

 may be entirely concealed, or revealed as only a faint mottling of 

 olive-brownish. 



The measurements of 40 eggs average 21.1 by 15.1 millimeters; 

 the eggs showing the four extremes measure 22.9 by 15.3, 22.8 by 

 16.3, 20.8 by 13.7, and 19.3 by 14.2 millimeters. 



Incubation. — A few records indicate a one-day pause between the 

 completion of the nest and the laying of the first egg, but usually 

 the first egg is laid the day the nest is finished, and one is then laid 

 each successive day until the clutch is complete. Effective incuba- 

 tion apparently begins with the 3rd or 4th egg in the usual 5-egg 

 clutch. In some cases it may start with the second egg, but apparently 

 almost never with the laying of the first egg. The variation in the 

 time of onset of incubation is evidenced by the commonly observed 

 spread of hatching over a 1- to 3-day period. Incubation is by the 

 female alone and is of 12 or 13 days duration, measured between 

 the laying and hatching of the last egg in the clutch. Data from 

 14 complete nest-histories showed eight 12-day incubation periods 

 and six of 13 days. 



As both Nelson (1887) and Brandt (1943) point out, the male stays 

 nearby during incubation and utters alarm notes when danger 

 threatens. Early during the incubation period the female's usual 

 reaction is to leave the nest when an intruder is still some distance 

 away, fly 10 to 20 or more yards, alight often near the male, and begin 

 foraging. Both birds may utter alarm calls, and the female may 

 fly from tussock to tussock or other vantage points while watching 

 the intruder. Usually within 5 or 10 minutes after the intruder 

 retires, she returns to the nest in a series of short flights interspersed 

 with brief periods of foraging and watching. The last abrupt flight 

 takes her directly to the nest; only once have I seen a female walk 

 to the nest. 



As the time of hatching approaches the attentiveness of the incu- 

 bating female increases noticeably. She shows a marked reluctance 

 to leave the nest and frequently remains on it until approached very 

 closely. Then she flies only a few feet, often chattering loudly and 

 plaintively. Alighting with wings slightly spread and drooped and 

 tail fanned against the ground, she runs fluttering in this position 

 away from the nest. The responses of individual females when 

 forced from the nest vary considerably. Some may omit either the 

 alarm notes or the distraction display, or both. 



