Paul Flint, Ph.D. (Former Employee)

We studied survival rates of Northern Pintail (Anas acuta; hereafter pintail) broods and ducklings along the lower Kashunuk River on the Yukon-Kuskokwim Delta, Alaska. Survival rates were determined for 770 ducklings in 111 broods. Brood sizes at hatch were smaller in 1993 versus 1991 and 1992. Duckling survival rates were lower than those reported in previous studies and differed among...

Lack (1967, 1968) proposed that clutch size in waterfowl is limited by the nutrients available to females when producing eggs. He suggested that if nutrients available for clutch formation are limited, then species producing small eggs would, on average, lay more eggs than species with large eggs. Rohwer (1988) argues that this model should also apply within species. Thus, the nutrition...

We studied nesting chronology and success of Northern Pintails (Anas acuta) on the coastal Yukon-Kuskokwim Delta, Alaska during the summers of 1991-1993. We found a total of 795 nests during three annual searches of a 27.4 km2 area. Minimum nest density averaged 9.67 nests per km2. Nesting success varied among years and ranged from 43.12% in 1991 to 10.74% in 1993 (average 23.95%). Most...

Egg size is an important determinant of reproductive investment by birds. For many species, total investment in a clutch is limited by the size of stored reserves (Ankney and MacInnes 1978, Esler and Grand 1994a). Egg size determines the unit by which these stored reserves are partitioned. Individual females in most species of waterfowl show a high repeatability for egg size, implying...

We used radio telemetry to study renesting by wild, free-ranging Northern Pintails (Anas acuta) on the coastal Yukon-Kuskokwim Delta in 1994 and 1995. Fifty-six percent of females (n = 39) renested at least once. Propensity to renest declined among females that initiated later first nests. Renesting interval was not related to female weight, year, or initiation date of first nests. Mean...

Survival of young is an important and poorly understood component of waterfowl productivity. We estimated survival of black brant (Branta bernicla nigricans) goslings during summers 1987-89 on the Yukon-Kuskokwim Delta, Alaska, to determine timing and magnitude of gosling mortality and to compare methods of estimating gosling survival. Eighty-two percent of radio-tagged adult females (n...

Radio transmitters are an important tool in waterfowl ecology studies, but little is known about their effects on free-ranging geese. We attached transmitters to female brant (Branta bernicla nigricans) to investigate migration schedules at a fall staging area, return rates to nesting grounds, and nesting rates of returning females in subsequent breeding seasons. Radio-tagged females (n...

Estimates of juvenile survival from hatch to fledging provide important information on waterfowl productivity. We develop a model for estimating survival of young waterfowl from hatch to fledging. Our model enables interchange of individuals among broods and relaxes the assumption that individuals within broods have independent survival probabilities. The model requires repeated...

Previous studies of waterfowl have measured nest attendance and nest temperature separately using a variety of methods. A device was developed that monitors nest attendance and temperature simultaneously. The device consists of an artificial egg with a microswitch that records nest attendance and a thermistor probe that records temperature. Data are stored in a single-channel data logger...

We studied relationships between body size of female Black Brant goslings (Branta bernicla nigricans) late in their growth period and first year survival, eventual adult body size, breeding propensity, and size and volume of clutches they eventually produced to examine the relationship between growth and fitness in this population. We indexed body size by calculating PC1 scores based on...

We studied behavior of broods of Black Brant (Branta bernicla nigricans) during five summers between 1987 and 1993, a period in which the local breeding population increased >3-fold. Goslings spent more time foraging than adults of either sex, while adult males spent more time alert and less time foraging than adult females. Percentage of time spent alert was positively correlated with...

We estimated the amount of incubation time that first laid Black Brent eggs received before completion of the clutch. First laid eggs received up to 48 hours of incubation before the last egg was laid in Brent clutches. Waterfowl clutches usually hatch within a period of 24 hours, suggesting that some mechanism reduces developmental asynchrony during incubation. The combination of...