
Factors affecting Number of Birds Observed 
A great many complicating factors as discussed in following para- 
graphs influence the number of birds which use a field as well as the ease 
of finding them, among which are the following: (1) time of season, 
(2) experience of personnel, (3) equipment, (4) weather conditions and 
field moisture, (5) moon phase, (6) time of night in field, (7) frequency 
of visits to field, (8) relationship of location of feeding field to 
daytime habitat, and (9) agricultural practices and natural succession. 
1. Time of season.--Migratory woodcock begin to arrive in Louisiana 
in late October; the number increases throughout November, and by Decem- 
ber 15 the maximum number is reached. The population remains somewhat 
steady until Late January or early February. With mild early springs, 
woodcock may leave the last week of January, but with prolonged cold 
weather they may remain as late as the third week of February. Counts | 
made before December 15 and after February 1 showed great fluctuations in 
numbers. 
2. Experience of personnel.--Some students were quite adept at see- 
ing woodcock eyes, while others had great difficulty in locating them; 
consequently the latter walked past many woodcock without seeing them. | 
Students who possessed the fortitude to remain in the field under adverse 
weather conditions saw more birds than those who went out only during 
fair weather. Tall students sighted more birds in fields with relatively 
dense cover thm did shorter ones, while those who tired easily saw fewer 
woodcock than those with greater stamina. In calculating man hours in 
the field, the time of all students was included regardless of performance. 
3. Equipment.--There is a great variation in the beam of light cast 
by night hunters! headlights. Although the type of beam preferred by a 
hunter was a personal matter, a medium-sized spot was better than a large 
or small one. The intensity of the beam from a six-volt light that made 
a large spot was too diffuse, thereby limiting the distance at which eyes 
of woodcock were seen. Many lights could not be focused properly. 
Exhausted batteries failed to produce a bright beam. The correct size of 
spot and intensity of beam were essential to the successful location of 
birds. / 
h. Weather conditions and field moisture.--Weather played a very 
important role in the activity of the birds as well as in the success of 
the hunter. Mm rainy days more birds utilized the nocturnal feeding sites 
than on dry days. Since wet vegetation was generally darker than dry 
vegetation, it provided a background against which eyes were easily 
located. Short droughts caused earthworms to go deeper in the soil with 
corsequent desertion of fields by woodcock. At the same time, there was 
often a marked increase in the number of woodcock in areas with a plenti- 
ful moisture supply. During heavy rains or snows, birds were difficult 
to see. High humidity was usually associated with large numbers of birds 
at nocturnal feeding sites. Moderate to slightly warm temperatures 
resulted in greater numbers of birds in fields than either cold or very 
warm temperatures. Few birds appeared in fields on nights with heavy 
a) 
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