Two hens neck-banded in 1975 were observed on their nests in the spring 

 of 1976 in the vicinity of their capture (appendix D), demonstrating the 

 tendency of breeding hens to return to the same areas to nest. Only five 

 observations of juvenile birds returning with their parents to nesting areas 

 were recorded. Migration to other breeding grounds, post-banding mortality, 

 and neck-band loss are the factors believed to be responsible for the 

 paucity of these observations. 



Crops and Forage Utilized . Feeding by breeding geese during this period 

 was largely limited to streamside fields and riparian vegetation. 



Movement . During the period of nest initiation, the breeding segment of 

 the population remained on the river most of the time, the females on or 

 near the nest and the gander on a territorial defense site. The gander 

 defended the territory from a small bar or island near the nest or from the 

 main bank where he could also graze on green vegetation. 



Nest Initiation . As shown in figure 5, nesting by Canada geese in the 

 study area began in late March in 1975 and mid-March in 1976. FAA records 

 from Miles City showed similar mid-March temperatures in both years. Both 

 years there was a peak in the dates of nest initiation, around April 12, 

 1975, and April 1, 1976. The later peak in 1975 may have been the result 

 of heavy snow and blizzard conditions in the study area during the first week 

 of April. A renesting and/or late-nesting peak in 1976 is not apparent in 

 figure 5 because these late nests were not surveyed. Late nesting followed 

 high rates of predation and desertion of early nests in the upstream study 

 sections (table 5). 



Nesting Density . Goose nesting densities were low overall, but on 

 certain islands (table 6) they approached or exceeded those found by other 

 researchers (table 7). This tendency of high numbers of geese to nest on 

 isolated islands may result from hens returning to nest on islands where they 

 successfully nested in previous years; this pattern may be disrupted by 

 predation as occurred on the most densely-nested island in the Miles City-to- 

 Kinsey section. In 1975, there were 2.5 nests/ha (1.0 nest/acre) on that 

 island, and, in 1975, similar numbers of hens began to nest there (table 6). 

 One or more raccoons, possibly attracted to the island by the large number of 

 nesting geese, preyed on all goose nests on the island shortly after these 

 nests were initiated. Later, four pairs of geese, two of which were success- 

 ful, renested or late nested on the island, a density of only .66 nests/ha 

 (.27 nests/acre). 



Nest Site Characteristics . In order to predict the effect of water with- 

 drawals from the river on goose nesting and on numbers of breeding, summering, 

 migrant, and wintering geese, these parameters were statistically compared with 

 the number of islands, sinuosity, gravel bar area, and area of agricultural 

 land, cottonwood-grassland, and dense cottonwoods in each section of river. 

 No significant correlations were found. However, the goose nest sites them- 

 selves were believed to have certain other characteristics in common. 



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