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The article discusses a study on the development of a general Bayesian modeling framework appropriate for estimating survival of both bird nests and their young. During the two-year study period, survival data of Common Goldeneyes ducklings located in central Alaska and in the Missouri Coteau region of North Dakota have been collected and analyzed. Goodness-of-fit of the fixed-effects models has been measured using a version of the Bayesian predictive value that evaluated the fit of empirical survival curve and the fit of predicted survival curve.

We studied duckling survival of lesser (Aythya affinis) and greater (A. mania) scaup at Minto Flats, Alaska during 2002-2003. We captured and marked 42 female scaup during the study, and we subsequently monitored survival of 32 scaup broods with 284 ducklings. Daily Survival Rate (DSR) of ducklings varied between years and was positively related to female body condition and duckling age. Estimated duckling survival to 30 days for both species of scaup was 0.24 (95% CI: 0.16 to 0.36) in 2002 and 0.03 (95% CI: 0.00 to 0.19) in 2003. Because we obtained little support for relationships between environmental covariates and duckling survival, we speculated that most of the variation between years could have been related to high rates of predation by gulls (Larus spp.) during 2003. Estimated recruitment of female scaup to 30 days (clutch size * nest survival * duckling survival * 0.5) was 0.30 (SE = 0.19) in 2002 and 0.01 (SE 0.01) in 2003. Given the low recruitment we observed at Minto Flats and the current population status of scaup, restriction of harvest of adult female scaup could be useful to support scaup populations at Minto flats. [ABSTRACT FROM AUTHOR]

We estimated variation in nest survival of lesser scaup (Aythya affinis) , greater scaup (A. mania) , and other common duck species at Minto Hats, Alaska, USA, during 1989-1993 and 2002-2003. Daily survival probability of scaup nests, as well as nests of all other duck species, varied with year, date, and nest habitat. Daily survival probability was unrelated to nest age and distance from the nest to water. Avenge, year-specific nest survival of all ducks at Minto Flats was 0.11 (95% CI: 0.05 to 0.22), comparable to nest survival of ducks breeding in mid-continent regions (i.e., the prairie pothole region and the Canadian prairie-parklands). Nest survival of scaup was variable among years, ranging from 0.01 (95% CI: 0.00 to 0.06) in 1992 to 0.61 (95% CI: 0.50 to 0.74) in 1993 and was probably related to variation in predation risk and water levels. Scaup production could have been limited by low nest survival during most years of this study; nest survival exceeded 20% only in 1993 and 2002. Because of the high densities of breeding scaup and other waterfowl species at Minto Flats, we recommend management to maintain existing habitat for breeding scaup and other duck species. This management could be most effectively informed by yearly monitoring of production to more accurately understand spatial and temporal variation in recruitment and to identify potential effects of proposed oil and gas exploration on recruitment of ducks at Minto Flats. [ABSTRACT FROM AUTHOR]

Summary 1.We estimated age-specific probability of breeding for black brant (Branta bernicla nigricans Lawrence) (hereafter brant) at the Tutakoke River Colony, Alaska, during a series of years in which local breeding density and juvenile mortality both increased. We use these analyses to examine demographic responses to increased population density. 2.Estimates of breeding probability were based on Kendall & Nichols (1995) full-likelihood modification of Pollock’s (1982) robust design applied to observations of uniquely colour-banded brant. 3.Breeding probability varied with female age but not across years, indicating lack of response to increased population density. Annual probability of breeding increased from 0·67 ± 0·042 for 2-year-old females to 0·90 ± 0·024 for females 5 years old or older. 4.Annual breeding probability of males ≥ 5 years old was 0·78 ± 0·03. Lower breeding probability of males compared to females probably reflects dispersal of males whose mates died. 5.Lower juvenile survival appears to be a general response to increased density in large herbivorous birds and mammals, while changes in adult survival and reproductive investment may be more variable. [ABSTRACT FROM AUTHOR]

Presents a reply to questions asked by James O. Leafloor and other researchers about the data and findings from a study by Mark S. Lindberg and Richard A. Malecki, which focused on the hunting vulnerability of Canadian geese. Date of Lindberg and Malecki's study; Providing of additional data to support original theory; Comparison of data.

Reports on the management conflicts regarding the difference of harvesting strategies presented by mixed locally breeding Canada geese and subarctic nesting races in Pennsylvania. Importance of neck band observations; Effect of season to flock composition; Hunting season population; Recommendations.

Examines the natal and breeding philopatry in a metapopulation of Black Brant birds in Alaska between 1986-1994. Reference to studies conducted on the dispersal and fidelity of birds; Examination of the natal dispersal of the male Black Brant; Comparison of estimates of philopatry to estimates of return rates.

Reports on the evaluation of breeding black brant at Tutakoke River, Alaska. Fidelity of nesting sites; Estimations of fidelity; Methods used; Result; References.

Presents a study which examined the use of brood-rearing sites by female Black Brant (Branta bernicla nigricans), on the Tutakoke River, Alaska, during 1987 to 1993. Fidelity to brood-rearing sites by adult females; Observation of site-specific and annual variation in movements among sites; Results of movement among brood-rearing sites for adults.