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• 1. [Article] Non-additive and non-stationary properties in the spatial distribution of a large marine fish population

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Royal Society and can be found at: http://rspb.royalsocietypublishing.org/...

  Citation × Citation Citation Abstract Copy Title: Non-additive and non-stationary properties in the spatial distribution of a large marine fish population Author: Ciannelli, Lorenzo, Chan, Kung-Sik, Bartolino, Valerio This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Royal Society and can be found at: http://rspb.royalsocietypublishing.org/. Title: Non-additive and non-stationary properties in the spatial distribution of a large marine fish population Author: Ciannelli, Lorenzo, Chan, Kung-Sik, Bartolino, Valerio This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Royal Society and can be found at: http://rspb.royalsocietypublishing.org/. Close

• 2. [Article] Population growth across heterogeneous environments: effects of harvesting and age structure

  This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/home/.

  Citation × Citation Citation Abstract Copy Title: Population growth across heterogeneous environments: effects of harvesting and age structure Author: Rouyer, Tristan, Yaragina, Natalia, Eikeset, Anne Maria, Hjermann, Dag O., Hidalgo, Manuel, Durant, Joel M., Stenseth, N. C., Ciannelli, Lorenzo This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/home/. Title: Population growth across heterogeneous environments: effects of harvesting and age structure Author: Rouyer, Tristan, Yaragina, Natalia, Eikeset, Anne Maria, Hjermann, Dag O., Hidalgo, Manuel, Durant, Joel M., Stenseth, N. C., Ciannelli, Lorenzo This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/home/. Close

• 3. [Article] Landscape dynamics and resulting species interactions: the cod-capelin system in the southeastern Bering Sea

  Capelin are a major component of cod diet in many ecosystems of the North Atlantic. In the Bering Sea, however, the percentage of capelin found in Pacific cod stomachs is negligible. We hypothesize that ...

  Citation × Citation Citation Abstract Copy Title: Landscape dynamics and resulting species interactions: the cod-capelin system in the southeastern Bering Sea Author: Ciannelli, Lorenzo, Bailey, Kevin Mclean Capelin are a major component of cod diet in many ecosystems of the North Atlantic. In the Bering Sea, however, the percentage of capelin found in Pacific cod stomachs is negligible. We hypothesize that the landscape (or ‘seascape’) features of hydrography and bathymetry of the Bering Sea impose a constraint on the distribution of cod and capelin that contributes to their spatial segregation and ultimately, to their uniquely weak trophic link. We analyzed a long-term data collection (1972 to 2001) on Pacific cod and capelin catches and feeding interactions, and developed a new metric to quantify the spatially explicit overlap between a predator and a prey. Our analysis indicates that cod and capelin distributions respond to the thermal conditions of the Bering Sea. Typically, a frigid water mass is present on the middle portion of the shelf, and cod distribution is confined to the southern side of the cold pool, while capelin is confined to the north. However, in warm years the middle shelf is penetrated by thermal gateways (between 1 and 6°C), allowing cod to invade the capelin habitat. In this situation, when cod and capelin overlap, cod feed heavily on capelin. The annual index of cod and capelin overlap is correlated with the Pacific Decadal Oscillation (PDO) index, a climate indicator of the North Pacific. The width of the thermal gateways in the middle shelf is also correlated with the PDO. These results point to a direct causal link, from climate and thermal conditions of the Bering Sea shelf, to cod and capelin distribution, and ultimately to their overlap and trophic interactions. Title: Landscape dynamics and resulting species interactions: the cod-capelin system in the southeastern Bering Sea Author: Ciannelli, Lorenzo, Bailey, Kevin Mclean Capelin are a major component of cod diet in many ecosystems of the North Atlantic. In the Bering Sea, however, the percentage of capelin found in Pacific cod stomachs is negligible. We hypothesize that the landscape (or ‘seascape’) features of hydrography and bathymetry of the Bering Sea impose a constraint on the distribution of cod and capelin that contributes to their spatial segregation and ultimately, to their uniquely weak trophic link. We analyzed a long-term data collection (1972 to 2001) on Pacific cod and capelin catches and feeding interactions, and developed a new metric to quantify the spatially explicit overlap between a predator and a prey. Our analysis indicates that cod and capelin distributions respond to the thermal conditions of the Bering Sea. Typically, a frigid water mass is present on the middle portion of the shelf, and cod distribution is confined to the southern side of the cold pool, while capelin is confined to the north. However, in warm years the middle shelf is penetrated by thermal gateways (between 1 and 6°C), allowing cod to invade the capelin habitat. In this situation, when cod and capelin overlap, cod feed heavily on capelin. The annual index of cod and capelin overlap is correlated with the Pacific Decadal Oscillation (PDO) index, a climate indicator of the North Pacific. The width of the thermal gateways in the middle shelf is also correlated with the PDO. These results point to a direct causal link, from climate and thermal conditions of the Bering Sea shelf, to cod and capelin distribution, and ultimately to their overlap and trophic interactions. Close

• 4. [Article] Variation in the energy density of forage fishes and invertebrates from the southeastern Bering Sea

  The quality and availability of forage fishes and invertebrates can affect the behavior and productivity of predators that rely on these resources. This study measures the proximate composition of forage ...

  Citation × Citation Citation Abstract Copy Title: Variation in the energy density of forage fishes and invertebrates from the southeastern Bering Sea Author: Whitman, Luke D. The quality and availability of forage fishes and invertebrates can affect the behavior and productivity of predators that rely on these resources. This study measures the proximate composition of forage fishes and invertebrates from the southeastern Bering Sea to estimate prey energy density (quality) using a method that is ecologically relevant. During the summers of 2008 and 2009, transect surveys were conducted near the Pribilof Islands in the southeastern Bering Sea to collect forage fishes and environmental data during the time when seabirds and fur seals were rearing their young on those islands. All forage species caught in sufficient numbers by trawling were analyzed for proximate composition to estimate prey quality, in terms of total energy density. Proximate composition of forage species from this area varied widely between years and among sampling locations. Much of the observed variation in prey energy density was explained by lipid content, which was inversely related to water content. Invertebrates exhibited greater variation in lipid content and energy density than did forage fishes, although their overall prey quality was similar to that of many forage fishes. Among forage fishes, northern lampfish (Stenobrachius leucopsarus) and northern smoothtongue (Leuroglossus schmidti) were found to have especially high lipid content and energy density. Estimates of total energy per individual for all prey types provide an alternate ranking of prey quality when compared to energy density, which may affect predators with certain foraging strategies. Juvenile walleye pollock (Theragra chalcogramma), of both age 0+ and age 1+, were the most numerically abundant forage fish species caught and are known to be an important prey type in this area. Age 0+ pollock caught in 2009 were larger and had higher energy density than those caught in 2008, however the relationship between fish size and energy density was the same during the two years. The energy density of individual pollock from both years varied among sampling locations, suggesting that the quality of individual prey items is affected by variation in the environment. However, point-specific measurements of ocean habitat did not explain the observed variation in energy density of juvenile pollock. Model selection indicated that size was by far the most important determinant of total energy density in 0+ pollock. This study observed a wide range in energy density and variation in the quality of these forage fishes and invertebrates will likely affect habitat use by predators seeking to optimize their use of this important prey resource. Title: Variation in the energy density of forage fishes and invertebrates from the southeastern Bering Sea Author: Whitman, Luke D. The quality and availability of forage fishes and invertebrates can affect the behavior and productivity of predators that rely on these resources. This study measures the proximate composition of forage fishes and invertebrates from the southeastern Bering Sea to estimate prey energy density (quality) using a method that is ecologically relevant. During the summers of 2008 and 2009, transect surveys were conducted near the Pribilof Islands in the southeastern Bering Sea to collect forage fishes and environmental data during the time when seabirds and fur seals were rearing their young on those islands. All forage species caught in sufficient numbers by trawling were analyzed for proximate composition to estimate prey quality, in terms of total energy density. Proximate composition of forage species from this area varied widely between years and among sampling locations. Much of the observed variation in prey energy density was explained by lipid content, which was inversely related to water content. Invertebrates exhibited greater variation in lipid content and energy density than did forage fishes, although their overall prey quality was similar to that of many forage fishes. Among forage fishes, northern lampfish (Stenobrachius leucopsarus) and northern smoothtongue (Leuroglossus schmidti) were found to have especially high lipid content and energy density. Estimates of total energy per individual for all prey types provide an alternate ranking of prey quality when compared to energy density, which may affect predators with certain foraging strategies. Juvenile walleye pollock (Theragra chalcogramma), of both age 0+ and age 1+, were the most numerically abundant forage fish species caught and are known to be an important prey type in this area. Age 0+ pollock caught in 2009 were larger and had higher energy density than those caught in 2008, however the relationship between fish size and energy density was the same during the two years. The energy density of individual pollock from both years varied among sampling locations, suggesting that the quality of individual prey items is affected by variation in the environment. However, point-specific measurements of ocean habitat did not explain the observed variation in energy density of juvenile pollock. Model selection indicated that size was by far the most important determinant of total energy density in 0+ pollock. This study observed a wide range in energy density and variation in the quality of these forage fishes and invertebrates will likely affect habitat use by predators seeking to optimize their use of this important prey resource. Close

• 5. [Article] Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Public ...

  Citation × Citation Citation Abstract Copy Title: Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies Author: Paredes, Rosana, Kuletz, Kathy J., Waluk, Chad M., Suryan, Robert M., Irons, David, Battaile, Brian C., Nordstrom, Chad A., Jones, Nathan, Trites, Andrew W., Benoit-Bird, Kelly J., Heppell, Scott A., Hoover, Brian To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Public Library of Science and can be found at: http://www.plosone.org/home.action. Title: Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies Author: Paredes, Rosana, Kuletz, Kathy J., Waluk, Chad M., Suryan, Robert M., Irons, David, Battaile, Brian C., Nordstrom, Chad A., Jones, Nathan, Trites, Andrew W., Benoit-Bird, Kelly J., Heppell, Scott A., Hoover, Brian To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Public Library of Science and can be found at: http://www.plosone.org/home.action. Close