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Table I - Description of Habitat Types Found on the Study Area 

Habitat Type Description 
Large Lakes Natural lakes or irrigation reservoirs, 300 surface acres 
or larger. 
Small Lakes and Lakes smaller than above, including small ponds or 
Ponds potholes. 
Slough Shallow water bodies containing emergent vegetation. 
River As normally defined. 
Creek As normally defined. 
Irrigation Canals Irrigation waterways over 8' wide, whose general function 
is to carry water long distances, mainly to irrigation 
reservoirs. 
Irrigation Ditches Irrigation waterways less than 8' wide, whose general 
function is to carry water to the fields. 
Drain Ditches Small waterways whose function is to carry underground 
water away from the fields. 
Methods 
Accurate comparison of air and ground breeding-pair counts depends a 
great deal on complete coordination between the air and ground teams. Because 
the Cache la Poudre study area is located centrally in the north-to-south migration 
path, a count of total breeding-pairs such as that taken further north would not 
reveal how many pairs would actually stay to nest on the area, It is necessary, 
therefore, to count only those pairs which have set up, or are attempting to set up 
territories. This means that only those pairs which are found by themselves and 
not in the company of other pairs, in addition to lone males or lone females, can 
be counted as representing a territory. Thus, training an aerial observer to 
recognize these things would be an important part of any technique which may evolve 
from this study. 
Ground Surveys 
The waterfowl breeding population on the township was determined by a 
series of counts initiated during the first part of April. All waterways on each 
section were walked and all water bodies scanned with a spotting scope at two-week 
intervals. Only those pairs which had apparently established territories were 
tallied and their location plotted on a map of the section. Sections were worked in 
Similar order for each coverage. 
Time of observation appears to be important, because farmers working in 
fields often flush birds from their chosen territories. For this reason work was 
confined to early morning hours (sunrise to about nine o'clock) and late afternoon 
(four o'clock to sunset). 
