Effects of Weather.--In order to evaluate the effects of various 
weather conditions on winnowing activity, the results of each winnow- 
ing count were plotted against wind speed, temperature and sky condi- 
tion. Since the three routes were of different length and each had a 
different snipe population, the total number of snipe recorded in the 
first minute of each 2-minute stop was plotted as a percentage of the 
average total for first-minute stops for that particular route. Simi- 
larly, totals from the second-minute counts were plotted as percentage 
of the average for all second-minute stops for that same route. This 
gave a total of 20 morning samples and 20 evening samples. 
Wind.--Wind speeds of 5 miles an hour or more invariably reduced 
winnowing activity below normal. Increases to 10 m.p.h. generally 
stopped all winnowing. This was by far the most important single 
factor influencing winnowing. 
Temperature.--Half of the morning counts were taken when the 
temperature at starting time was between 30° and 0? F, The other 
half were made with temperatures between 0° and 55°... All of the 
cool mornings produced results above the average; on all of the warmer 
mornings, results were near or below average. On the two days when the 
early morning temperature was above 5(©, the counts were especially low 
(45 to 75 percent of average); on one of these days a wind of 5 to10 
mepeh. and light rain may well have teen the primary factors in the low 
count rather than the temperature, but on the other day there was no 
precipitation and the wind was calm. 
No correlation was found between evening temperatures and snipe 
winnowing activity. 
Sky Condition.--Clear skies in the early mming were associated 
with average amount of winnowing (within 20 percent), with tendency to 
be above average rather than below. Clear skies in the evening were 
associated with much more variable results (from 0 percent below aver- 
age to hO percent above average). There were only two nights with the 
sky about half covered with clouds, and on one of these the wind speed 
was 5 m.p.h. and there was very little winnowing; on the other night 
results were close to normal. On calm, overcast evenings and mornings 
winnowing was very variable, ranging from 45 percent above normal to 55 
percent below. Rain gave definitely inferior results; but early morning 
fog, on the two days when it occurred, was associated with near average 
winnowing, on one date, and with the very highest amount (60 to 80 per- 
cent above normal) on the other. 
Gustiness.~-Correlation of winnowing activity with the observed 
variables of wind, temperature and sky condition suggest that another 
factor, closely connected with these three, may actually be the most 
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