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Most seabirds breed colonially and exhibit considerable site fidelity over the course of their long lifespans. Initial colony selection can therefore have substantial fitness consequences, but factors contributing to recruitment into colonies and subsequent fidelity remain unclear. We used multi-state capture-recapture models to test several hypotheses related to apparent fledgling survival, probability of recruitment to natal colonies, and apparent post-recruitment survival in Black-legged Kittiwakes Rissa tridactyla, using data from individuals banded as chicks and subsequently resighted at a colony in south-central Alaska over a 20-year period. Competitive models suggested that apparent fledgling survival declined throughout our study. This decline was likely driven by intrinsic, cohort-specific processes and was not explainable by post-fledging weather or climate conditions. Independent resightings at other colonies suggest the apparent decline may have been at least partially influenced by permanent emigration (natal dispersal), which occurred more frequently when the colony size was large. Recruitment was primarily age-dependent, with no detectable effects from early life experience or from annual changes in four factors: colony size, colony productivity, climate, or average weather conditions. We estimated an average recruitment age of seven years, which is older than typically reported for Atlantic kittiwake populations and which supports a more conservative life history strategy for kittiwakes in the Pacific. Variation in the apparent survival of recruits was cohort-specific and did not correlate with age or annual changes in the factors listed above. Instead, apparent survival of recruits was best explained by colony size during a cohort's second year, suggesting a degree of negative density dependence in post-recruitment survival or fidelity. This information could prove useful to managers deciding how to allocate resources among small, growing colonies and large, well-established colonies. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the use of a paired logistic regression method for determining important marine habitat areas of the Kittlitz's murrelet seabird in Prince William Sound, Alaska. Findings show that the introduced model was robust and efficient in identifying daytime marine habitat areas for the seabird.

The article explores the migration routes of Arctic Terns Sterna paradisea breeding in Prince William Sound, Alaska. The experiment was conducted using geolocator tags on 20 individuals in June 2007. The results of the research showed that challenging sea and weather conditions, and not paucity of food, may have deterred further movement of the terns south along the Chilean coast.

The article discusses a study of the distribution, abundance and trend estimates of the Kittlitz's Murrelet Brachyramphus brevirostris in Prince William Sound (PWS), Alaska from 1972 and 2007. A population model was developed for the study using the field estimates and variances for Marbled, Kittlitz's and unidentified murrelets. The populations of Brachyramphus murrelets were found to be declining based on field and model estimates. The possible role of a regional, contemporaneous alteration in the environment in the long-term decline of the two species is mentioned. Also emphasized is the need to include the Brachyramphus species in a list of conservation priorities.

Focuses on a study which examined the ecology of color forms in populations of Carcinus maenas on the southern New England coast for comparison with native populations. Information on the collecting sites and methods; Results; Discussion.

The article focuses on a study that analyzed survey data as a part of the Symposium on Population Status and Trends of Kittlitz's Murrelet in Prince William Sound (PWS), Alaska, between 1989 and 2007. The study showed that Brachyramphus murrelets in PWS declined by about 68 percent between 1989 and 2007.