Breeding biology and diet of Herring Gulls Larus argentatus were studied on Ile Nue, in the Mingan Archipelago National Park Reserve, in the Gulf of St. Lawrence. Nesting parameters were measured 1994--1996, and fledging success and diet were followed in 1996. Clutch size was low in all three years of the study, and hatching success was low in 1995. Low clutch size and hatching success could not be explained by researcher disturbance, predation, or competition for nest sites, leaving food-stress as the most likely explanation. To reduce the biases associated with determining diet, we used four methods to estimate diet. The 1996 breeding season was divided into three periods using changes in the number of gulf pellets collected from roost sites as an indirect measure of dietary changes; these periods corresponded to the pre-spawning, spawning, and post-spawning periods of capelin Mallotus villosus. (Abstract shortened by UMI.)

The conflict over the herring run at Kah Shakes is complicated. In 1991, the Alaska Department of Fish and Game (ADFG) expanded the commercial herring sac roe fishing boundary in the Revillagigedo Channel to include Cat and Dog Islands. Native and non-Native local residents of Ketchikan protested the boundary expansion, as did managers of the neighboring Annette Island Fishery managed by the local reservation. Using cultural anthropological research methods that include ethnographic data, semi-structured, qualitative interviews gathered in southeast Alaska in 2008, and a comprehensive literature review of historic data culled from newspapers and other texts, I examine the many political factors that contribute to this conflict, including the contest between anecdotal and scientific data, the construction of fisheries management boundaries, and issues of collective memory. Using Vayda and Walters' event ecology methodology, bolstered by discourse analysis, I identify three discourses (local ecological knowledge, management and environmental). I use these discourses as comparative units to show that little coincident data can be identified between these discourses. I examine two areas of dissident data, stock definition and measures of abundance, and recommend that local ecological knowledge (LEK) be used to expand the scientific database on which current management techniques depend, to question the accuracy of current ADFG management boundaries and stock identification, and to recalibrate guideline harvest levels by exposing the effects of shifting baselines. I then outline how Geographic Information Systems (GIS) may assist in the validation and integration of LEK into the current fisheries management paradigm to create a more holistic narrative of ecological change.

No description available.

Pelagic forage fishes play critical roles in productive marine food webs by providing a link between zooplankton and piscivores and transferring energy from feeding grounds to other ecosystems. The amount of energy moved to higher trophic levels or new systems is directly linked to the consumption rate of pelagic forage fishes. In the Gulf of Maine, Atlantic herring (Clupea harengus) is the dominant forage fish; the purpose of this study is to determine their specific consumption rate (g prey/g fish/day). Using fish collected in autumn 2012 and spring 2013, we applied a mercury mass-balance model to estimate individual and population consumption of Atlantic herring in the Gulf of Maine. Our results suggest that the specific consumption rate increases from age 1.5 until age 6 (years) and then asymptotes. These estimates were contradictory to much of what exists in the literature; for most fishes, specific consumption estimates decrease with age and overall are much lower than our estimates. We looked further into our results to explore the underlying cause of the increase in specific consumption rate. We combined the mercury mass-balance model with a Wisconsin (WI) bioenergetics model and ran several simulations adjusting the most sensitive factors in each--prey mercury in the former and activity in the latter. The results of our simulations showed that an increase in activity relative to age and mass can best explain the increase in the consumption rate of Adult herring. This suggests that an ontogenetic shift to migration in adult Atlantic herring results in increased energy demand with age, and ultimately increased consumption.

Graduation date: 1964

Thesis (M.Sc.)--Memorial University of Newfoundland, 2000. / Includes bibliographical references.

Thesis (M.S.)--University of North Carolina Wilmington, 2009. / Title from PDF title page (January 12, 2010) Includes bibliographical references (p. 85-95)

Thesis (Ph. D.)--University of Rhode Island, 2004. / Typescript. Includes bibliographical references (leaves 104-106).

The harbor porpoise is considered a threatened species in Swedish waters. A full understanding of its ecology and relationship to other species is important when designing effective conservation plans. This thesis aims to investigate the relationships between harbor porpoises and their prey by comparing the acoustic activity patterns of harbor porpoises and the movement patterns of some of their prey species available at Kullaberg, Sweden. For this purpose, the scientific literature of porpoise and fish activity patterns has been reviewed. Results show that harbor porpoises may follow vertically migrating herring, but further studies are needed to confirm this. It is also possible that the activity pattern of porpoises does not follow exactly the movements of a certain species of prey, but that they rather feed upon several species, and therefore change their behavior accordingly throughout the diurnal cycle.

Univ., Diss.--Göteborg, 2005. / Literaturverz. S. 210 - 221.