ROSENEATA AREA BROOD STUDY, HAHITOBA, 1949 
Charlies D. Trane 
Thia aumier a project was undertaken in Reoseneath Municipality near 
Minnedosa, Manitoba in an attempt to furnish data which would be of value 
in assessing the preductivity of waterfowl breeding areas, 
Of primary intereat was a eatudy of the extent of overland movement of 
broeds ae well as the factors which caused pouch movement. Some observationa 
were aiso made on activity patterns of broode and on juvenile mortality and 
brood breakup, Asp a reevlt of the intensive coverage given the aress during 
the etudy it was poseible to make an estimate of lte productivity in terme 
of broods per aguare mile. 
The Ares 
A study block one and one-half scusre miles was selected in dietrict 
& (Newdale-Erickson}. Ineluded in the study hlock are 4F permanent, 36 semi- 
rermanent potholes, and about EO temvorary waters. The accompanying nmap ehowe 
permanent and semi-permanent waters. 
The emergent vegetation eurrounding ungrazed potholes in cultivated 
arean congiate largely of whitetop (Fluminpes festucaces) and a large red re 
(Carex sp./ growing generally about Sa feet high. Graged potholes usually 
have marginal vegetation dominated by cattail (Typha jatifolja), hardstem 
bul ruch (Scirper acutyus) or softetem bul rush (Scirpue validug}; and have a 
freater diversity of vegetation including submerged aquatics. 
A permanent camp was set up in the southwest corner of the area in 
order that close contact could be maintained with the birds from dune 12 to 
August 29. 
Methodg 
The groundwork for the study consisted of locating nests and marking 
the broods, Margine of potholes were searched for diving duck neste and 
drives were made on foot for river duck nests. The ducklinge were marked 
by injecting water soluble aniline dyes of low toxicity Into the egez during 
incubation. This served to color the down and wae visible three to four weeks 
after the young had hatched. 
When the marked broode had hatched, every effort war made to locate 
them and record their movements. Three methods were used to accomplieh this. 
Beating through the marginal cover of potholee served to drive many broode 
into the open, but wat not completely effective when done by a single observer. 
Some breeds, particularly of river ducks, circled the potholes without showing 
themselves or Tan up oo ehore and could not be driven out. The area could be 
covered more guickiy but somewhat lees thoroughly by approaching potholes 
quietly in the evening when most of the broode were in the open. The moet 
thorough searches were made by taking up a hiding place close to the shore in 
the erening. Usually after a half hour of waiting the breeds began morlng 
into the open and in the course of an evening the observer could he fairly 
certain of seeing all the birde on a water ares. By far the best results were 
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