WILSON'S SNIPE WINTERING GROUND STUDIES, 1950-51 
Chandler S. Robbins 
U. S. Fish and Wildlife Service 
From January 8 through February & the writer carried on investiga- 
tions on the wintering grounds along the Gulf coast from Pensacola, Florida, 
to Galveston, Texas. These investigations included testing various census 
methods, obtaining preliminary census data for future comparisons, con- 
ferring with local field men, and trying various methods of trapping snipe 
for banding. 
Census methods.--Since the winter distribution of the Wilson's Snipe 
varies from year to year and even from week to week as a result of chmg- 
ing water levels, this is a very difficult species to census. Any one of 
a great many variable factors may produce shifts in local wintering popuia- 
tions, and these shifts quite frequently may cause apparent changes in 
abundance which are much greater than any actual changes, and which bear 
no relation to increases or decreases in the population as a whole. Some 
of the factors influencing snipe distribution in mid-winter in the Gulf 
coast states are: 
‘(1) Water levels in the uplands as influenced by recent and ac- 
cumulated precipitation and by rate of evaporation; 
(2) Water levels in well-drained tidal areas as influenced by 
position of moon, direction and velocity of wind, storms, construction 
of new canals, etc.; | ; 
(3) Water levels in poorly drained brackish marsh as influenced 
by storm tides, precipitation and evaporation; 
(4) Amount of grazing; : 
(S) Human disturbance, including legal and illegal shooting; 
(6) Rotation of crops, especially rice; 
(7) Changing of farm practices and crops due to labor costs, new 
-machinery, etc.; . 
(8) Natural edaphic changes; land becoming drier; 
(9) Reclamation projects; 
(10) Cold weather locally or to the north. | 
Due to these many disturbing factors, md due to the fact that 
subsequent counts in a given area result in significant changes in the 
number of snipe recorded even when none of the above factors are known 
to have interfered, a great many sample counts are necessary to obtain a 
reliable index to the population of the snipe on its wintering grounds. 
1951 counts.--The following counts scattered throughout the area 
visited in January 1951 may serve as some basis for future comparisons, 
but it is planned to initiate much more extensive counts starting with 
the winter of 1951-52. 
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