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Parental care is necessary for the survival of most mammalian offspring. However, this is especially true for neonatal sea otters ( Enhydra lutris ), which are the most altricial of marine mammals born at sea. The female not only feeds the pup but also protects it from environmental and predatory threats while maintaining the insulating properties of its fur for thermoregulation. We studied the behavior of female sea otters and their pups during the first three months postpartum in Simpson Bay, Alaska. Six behaviors for females and seven behaviors for pups were recorded to produce 24-h activity budgets. Pups were classified into three behavioral/size categories: Category 1 (C1) 0 – < 4 wks old; Category 2 (C2) 4 – < 8 wks old; Category 3 (C3) 8–12 wks. The percentage of time females spent feeding increased from 9% (C1) to 32% (C3) reflecting the increased nutritional requirements of the maturing pups. C1 females spent 21% of their time swimming in a meandering manner, possibly to protect young pups from predation, which decreased to 8% for females with C3 pups. The time spent resting by females (ca. 50%) was independent of pup category. C1 pups spent 83% of their day resting which decreased to 48% for C3 pups. Time spent nursing remained constant (ca. 8%) for all pup categories, but feeding on solid food provided mainly by the female increased to 17% (C3 pups). The percentage of time that pups spent swimming increased to 17% (C3 pups) as they developed strength and coordination. Our results provide a quantitative picture of the changes in female and pup behavior and activity patterns during the early and critical developmental stages of altricial pups at sea. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the natural and human influences that affect incubation patterns and sex role in Black Oystercatcher (Haematopus bachmani) in Alaska. Researchers used 24-hour-per-day video monitoring of breeding pairs to examine incubation patterns. The study found that female and male shorebirds have different but complementary incubation patterns, which facilitates an efficient egg care, and are affected by disturbance and nest predation threats.

We examined King Eider (Somateria spectabilis) brood survival in the Kuparak oil field in northern Alaska in 2002 and 2003 by monitoring hens with broods using radiotelemetry. We observed complete brood loss in eight of 10 broods. Broods survived less than 2 weeks on average, and most mortality occurred within 10 days of hatch. Distance hens traveled overland did not affect brood survival. Apparent King Elder brood survival in our study area was lower than reported for eider species in other areas. We recommend future studies examine if higher densities of predators in oil fields reduces King Eider duckling survival. [ABSTRACT FROM AUTHOR]

Determines whether there are differences in maternal attendance between a declining population and a stable population of stellar sea lions in Alaska. Behavioral responses to reduced prey availability; Comparison of mean length of foraging trips between the two populations; Mean perinatal period; Mean length of shore visits.

Presents a study that examined patterns of parental care in crested auklets, a monogamous seabird, for three breeding seasons in the Aleutian Islands, Alaska using radio-telemetry. Comparison of the rate of male and female provisioning and breeding site attendance; Differences in the linear growth rate between chicks with parents with and without transmitters; Examination of colony-level productivity; Analysis of the vulnerability of chicks to attacks.

We used a supplemental-feeding experiment, the doubly labeled water technique, and a model-selection approach based upon the Akaike Information Criterion to examine effects of food availability on energy expenditure rates of Black-legged Kittiwakes, Rissa tridactyla, raising young in Middleton Island, Alaska. Energy expenditure rates of females were more responsive to fluctuations in food availability than those of males. Our objectives were to determine if the energy expenditure rates of parent kittiwakes provided with supplemental food, differed from those of control parents, and to determine the strength of the relationship between parental energy expenditure rates and a suite of extrinsic and intrinsic covariates and factors. Fed males likely expended more energy while off the nest than fed females, possibly because of nest defense. Energy expenditure rates of fed kittiwakes were similar to values reported for kittiwakes that were either not raising young or not foraging. Fed kittiwakes increased their reproductive output while simultaneously decreasing parental effort and increasing body condition. Parent kittiwakes, therefore, adjusted parental effort in response to variation in breeding conditions due to changes in food availability. Adjustments in reproductive effort in response to variable foraging conditions may have significant effects on the survival and productivity of individuals, and thus provide substantial fitness benefits for long-lived seabirds such as Black-legged Kittiwakes. Differences in survival rates between the sexes may occur if each sex experiences a different survival curve with respect to field metabolic rate or parental effort.