Descriptive Key to the Otoliths of Gadid Fishes of the Bering, Chukchi, and Beaufort Seas

An illustrated key with supplementary descriptive material is presented for six species groups of gadid fishes which are of trophic importance in the Bering, Chukchi, and Beaufort seas. These species include: Arctogadus spp. Drjagin, Boreogadus saida (Lepechin), Eleginus gracilis (Tilesius), Gadus macrocephalus Tilesius, Microgadus proximus (Girard), and Theragra chalcogramma (Pallas)

Waved albatrosses can navigate with strong magnets attached to their head

The foraging excursions of waved albatrosses Phoebastria irrorata during incubation are ideally suited for navigational studies because they navigate between their Galápagos breeding site and one specific foraging site in the upwelling zone of Peru along highly predictable, straight-line routes. We used satellite telemetry to follow free-flying albatrosses after manipulating magnetic orientation cues by attaching magnets to strategic places on the birds' heads. All experimental, sham-manipulated and control birds, were able to navigate back and forth from Galápagos to their normal foraging sites at the Peruvian coast over 1000 km away. Birds subjected to the three treatments did not differ in the routes flown or in the duration and speed of the trips. The interpretations and implications of this result depend on which of the current suggested magnetic sensory mechanisms is actually being used by the birds

Beluga Whale and Spotted Seal Use of a Coastal Lagoon System in the Northeastern Chukchi Sea

Aerial surveys were conducted in the northeastern Chukchi Sea during 1989-91 to investigate the distribution and abundance of beluga whales and spotted seals. Emphasis was on the 170 km long Kasegaluk Lagoon, which was known to be regularly used by both species during the open-water season. Belugas were seen on every survey during 3-14 July 1990 and 4-16 July 1991, with numbers ranging from 7 to 1212. Data from other years indicate that whales sometimes arrive as early as 22 June and leave the area by late July. The presence of nearshore gravel beds and warm, low-salinity water probably combine to make this region important as a place for belugas to molt. Spotted seals occur in the area from mid-July through early November. They haul out on particular spits and shoals near Utukok Pass, Akoliakatat Pass, and Avak Inlet. Numbers counted were variable but exceeded 1000 on many days in July, August, and September. Telemetry data suggest that the maximum count of about 2200 represents only a small portion of the total number of seals frequenting Kasegaluk Lagoon. Comparisons with data from previous years suggest that the numbers of belugas and spotted seals using the area have been relatively stable since the late 1970s. Activities associated with oil, gas, coal, and mineral resource development should be regulated to minimize their potential impacts on important beluga and spotted seal habitats.Key words: beluga whale, Delphinapterus leucas, spotted seal, Phoca largha, Chukchi Sea, Kasegaluk Lagoon, distribution, abundanceOn a effectué des relevés aériens dans la partie nord-est de la mer des Tchouktches au cours de la période allant de 1989 à 1991 dans le but d'enquêter sur la distribution et le nombre de bélougas et de veaux marins en se concentrant sur la lagune Kasegaluk longue de 170 km, qui avait la réputation d'accueillir régulièrement les deux espèces durant la saison d'eau libre. On a aperçu des bélougas lors de chacun des relevés effectués du 3 au 14 juillet 1990 et du 4 au 16 juillet 1991, en nombres allant de 7 à 1212. Les données provenant d'autres années révèlent que les baleines arrivent parfois dans la région dès le 22 juin et la quittent fin juillet. La présence de bancs de galets à proximité du rivage combinée à une eau tempérée et une faible salinité explique l'importance de cette zone comme site pour la mue des bélougas. Les veaux marins sont dans la région de la mi-juillet jusqu'au début novembre. Ils vont à terre sur des flèches littorales et des bancs de sable à proximité d'Utukok Pass, d'Akoliakatat Pass et de l'inlet Avak. Leur nombre variait mais était très souvent supérieur à 1000 en juillet, août et septembre. Les données de télémesure suggèrent que le nombre maximal d'environ 2200 ne représente qu'une petite partie du total des veaux marins fréquentant la lagune Kasegaluk. Des comparaisons avec des données provenant d'années antérieures suggèrent que le nombre des bélougas et des veaux marins qui utilisent la région est resté assez stable depuis la fin des années 1970. Les activités reliées à l'exploitation du pétrole, du gaz, du charbon et des ressources minérales devraient faire l'objet d'une réglementation afin que soient minimisées les retombées potentielles sur l'habitat du bélouga et celui du veau marin.Mots clés: bélouga, Delphinapterus leucas, veau marin, Phoca largha, mer des Tchouktches, lagune Kasegaluk, distribution, abondanc

Feeding of Bearded Seals in the Bering and Chukchi Seas and Trophic Interaction with Pacific Walruses

Current and historical information about food habits of bearded seals, Erignathus barbatus, are presented. Shrimps, crabs, and clams are overall the most important prey. Proportions of different prey in the diet vary with age of seals, location, and time of year. Foods of male and female seals are similar. Young seals eat proportionally more shrimps than do older animals. Recently, clams were important in the diet only in Norton Sound and near Wainwright, and only during late spring and summer. Greatest quantities of food were found in stomachs of seals which had eaten mostly clams. In Bering Strait, seals taken in spring 1958 and 1967 had consumed large quantities of clams, but this item was only a minor fraction of foods in 1975-79. Walruses, Odobenus rosmarus, have increased steadily in numbers since 1960. Whereas Bering Strait was mainly a route through which walruses migrated in spring and autumn, this region is now an area in which large numbers (up to 80,000) spend portions of the summer and autumn. The walruses feed mainly on clams. Increased foraging activity of walruses may have reduced availability of this food item for bearded seals. The walrus population currently appears to be exhibiting indications of stress. These indications may be a reflection of walrus numbers at or in excess of the ability of the clam resource to withstand current predation by walruses. Indices of population condition in bearded seals have remained stable, perhaps due to their more euryphagous habits

Factors Affecting the Observed Densities of Ringed Seals, Phoca hispida, in the Alaskan Beaufort Sea, 1996-99

Aerial surveys were conducted during late May and early June 1996-99 in the central Beaufort Sea of Alaska, using strip-transect methods. The purpose of these surveys was to quantify and model the effects of environmental covariates on ringed seal counts and to provide density estimates that would be useful for evaluating trends in seal abundance. Total survey effort included 40-88 transect lines per year covering 1198-2701 km². Observed densities ranged from 0.81 seals/km² in 1996 to 1.17 seals/km² in 1999. We examined the effects of habitat, weather, and time of day on observed seal densities, using univariate chi-square goodness-of-fit tests. We also used a multivariate generalized linear model to estimate the relationship between seal counts and covariates. Three habitat-related variables - water depth, location relative to the fast ice edge, and ice deformation - had substantial and consistent effects. The highest densities occurred at depths between 5 and 35 m. Densities were also highest in relatively flat ice and near the fast ice edge, declining both shoreward and seaward of that edge. Univariate analysis suggested that observed densities were generally highest at about 1200 h Alaska daylight time, but time was not a significant variable in the generalized linear models. Analyses of the effects of weather factors on seal counts were inconclusive. This was likely at least partially because temperature and wind speed were measured at survey altitude, rather than on the ice surface, and surveys were conducted only in weather considered suitable for hauling out. The final multivariate model did not account for a substantial proportion of the variation in seal counts. We think this result was largely due to date-related variation in the proportion of seals hauling out, an issue our surveys were not suited to address.De 1996 à 1999, à la fin de mai et au début de juin, on a effectué des relevés aériens dans la partie centrale de la mer de Beaufort alaskienne, en utilisant des méthodes d'échantillonnage en bande. Ces relevés avaient pour but de quantifier et de modéliser les effets de covariables environnementales sur le comptage des phoques annelés, et de fournir des estimations de densité qui pourraient servir à évaluer les tendances dans l'abondance des phoques. Le travail de relevé a porté chaque année sur un total allant de 40 à 88 lignes-transects, couvrant une superficie de 1198 à 2701 km². Les densités observées allaient de 0,81 phoque par km² en 1996 à 1,17 phoque par km² en 1999. On a étudié les effets de l'habitat, du climat et du moment de la journée sur les densités de phoques observées, à l'aide de tests d'adéquation chi carré à une variable. On a également eu recours à un modèle linéaire généralisé à plusieurs variables pour évaluer le rapport entre les comptages de phoques et les covariables. Trois variables reliées à l'habitat - profondeur de l'eau, position par rapport à la lisière de la banquise côtière et déformation de la glace - avaient des effets importants et constants. Les plus fortes densités se produisaient à des profondeurs de 5 à 35 m. Elles se retrouvaient également sur la glace relativement plane et près de la lisière de la banquise côtière, diminuant à la fois en direction du rivage et en direction de la mer depuis la lisière. L'analyse à une variable suggère que les densités observées étaient généralement plus fortes à environ 12 h (heure avancée de l'Alaska), mais le moment de la journée ne constituait pas une variable d'importance dans les modèles linéaires généralisés. Les analyses de l'impact des facteurs météorologiques sur les comptages de phoques n'ont pas donné de résultats concluants. Ceci était probablement dû au moins en partie au fait que la température et la vitesse du vent étaient mesurées à l'altitude où se faisaient les relevés plutôt qu'à la surface de la glace, et les relevés n'étaient effectués que par temps jugé approprié pour que les phoques montent sur la glace. Le modèle final à plusieurs variables ne représentait pas une proportion substantielle de la variation dans les comptages de phoques. Ce résultat, selon nous, était dû en grande partie à une fluctuation reliée à la date dans la proportion de phoques qui montaient sur la glace, question que nos relevés n'étaient pas conçus pour aborder

The Abundance of Harbor Seals in the Gulf of Alaska

The abundance of harbor seals (Phoca vitulina richardii) has declined in recent decades at several Alaska locations. The causes of these declines are unknown, but there is concern about the status of the populations, especially in the Gulf of Alaska. To assess the status of harbor seals in the Gulf of Alaska, we conducted aerial surveys of seals on their haul-out sites in August-September 1996. Many factors influence the propensity of seals to haul out, including tides, weather, time of day, and time of year. Because these “covariates” cannot simultaneously be controlled through survey design, we used a regression model to adjust the counts to an estimate of the number of seals that would have been ashore during a hypothetical survey conducted under ideal conditions for hauling out. The regression, a generalized additive model, not only provided an adjustment for the covariates, but also confirmed the nature and shape of the covariate effects on haul-out behavior. The number of seals hauled out was greatest at the beginning of the surveys (mid-August). There was a broad daily peak from about 1100-1400 local solar time. The greatest numbers were hauled out at low tide on terrestrial sites. Tidal state made little difference in the numbers hauled out on glacial ice, where the area available to seals did not fluctuate with the tide. Adjusting the survey counts to the ideal state for each covariate produced an estimate of 30,035 seals, about 1.8 times the total of the unadjusted counts (16,355 seals). To the adjusted count, we applied a correction factor of 1.198 from a separate study of two haul-out sites elsewhere in Alaska, to produce a total abundance estimate of 35,981 (SE 1,833). This estimate accounts both for the effect of covariates on survey counts and for the proportion of seals that remained in the water even under ideal conditions for hauling out

The Abundance of Harbor Seals in the Gulf of Alaska

The abundance of harbor seals (Phoca vitulina richardii) has declined in recent decades at several Alaska locations. The causes of these declines are unknown, but there is concern about the status of the populations, especially in the Gulf of Alaska. To assess the status of harbor seals in the Gulf of Alaska, we conducted aerial surveys of seals on their haul-out sites in August-September 1996. Many factors influence the propensity of seals to haul out, including tides, weather, time of day, and time of year. Because these “covariates” cannot simultaneously be controlled through survey design, we used a regression model to adjust the counts to an estimate of the number of seals that would have been ashore during a hypothetical survey conducted under ideal conditions for hauling out. The regression, a generalized additive model, not only provided an adjustment for the covariates, but also confirmed the nature and shape of the covariate effects on haul-out behavior. The number of seals hauled out was greatest at the beginning of the surveys (mid-August). There was a broad daily peak from about 1100-1400 local solar time. The greatest numbers were hauled out at low tide on terrestrial sites. Tidal state made little difference in the numbers hauled out on glacial ice, where the area available to seals did not fluctuate with the tide. Adjusting the survey counts to the ideal state for each covariate produced an estimate of 30,035 seals, about 1.8 times the total of the unadjusted counts (16,355 seals). To the adjusted count, we applied a correction factor of 1.198 from a separate study of two haul-out sites elsewhere in Alaska, to produce a total abundance estimate of 35,981 (SE 1,833). This estimate accounts both for the effect of covariates on survey counts and for the proportion of seals that remained in the water even under ideal conditions for hauling out

Dive Behavior of Eastern Chukchi Beluga Whales (Delphinapterus leucas), 1998–2008

We provide an exploratory description of the dive behavior of 23 beluga whales of the eastern Chukchi Sea stock, tagged with satellite-linked time and depth recorders at Point Lay, Alaska, between 1998 and 2007. Because of differences in how transmitters were parameterized, we analyzed data from tags deployed from 1998 to 2002 (n = 20 tags) and data from tags deployed in 2007 (n = 3 tags) separately. Using cluster analysis, we found three basic dive types in the 1998–2002 dataset. “Shallow” diving behavior was characterized by dives mostly 50 m in depth. “Intermediate” diving behavior was characterized by having one mode near the surface and a second mode near 250 m. “Deep” diving behavior was characterized by having one mode near the surface and a second mode more than 400 m from the surface. The average number of dives per hour ranged from 5.1 (SD = 2.1) to 9.8 (SD = 2.9) across dive types, with the fewest dives per hour in the deep diving category. In general, duration of dives ranged from 1 to 18 minutes; however, dives up to 21 minutes occurred in the deepest diving category. We found little evidence that dive behavior of the belugas in our sample varied by sex or age. In general, belugas dove more deeply in the eastern Beaufort Sea than in the western Beaufort or Chukchi Seas. The depths to which belugas most commonly dive in Barrow Canyon and along the Beaufort shelf break (200–300 m) correspond to the boundary where colder Pacific water overlies warmer Atlantic water, which is probably where Arctic cod (Boreogadus saida) are most dense. Diving depths within the Arctic Basin suggest that belugas are foraging mostly within the warm layer of Atlantic Water (~200–1000 m).Nous dressons une description exploratoire du comportement de plongée de 23 bélugas du cheptel de l’est de la mer des Tchouktches dotés de marqueurs d’enregistreurs satellitaires de profondeur temporelle à Point Lay, en Alaska, entre 1998 et 2007. En raison des différences de paramétrage des transmetteurs, nous avons analysé séparément les données de marqueurs déployés de 1998 à 2002 (n = 20 marqueurs) et les données de marqueurs déployés en 2007 (n = 3 marqueurs). Grâce à une analyse par grappes, nous avons trouvé trois types de plongée fondamentaux dans l’ensemble des données de 1998 à 2002. Le comportement de plongée « en eau peu profonde » était principalement caractérisé par des plongées de 50 m de profondeur. Le comportement de plongée « intermédiaire » était caractérisé par un mode de plongée près de la surface et un autre mode à près de 250 m. Le comportement de plongée « en profondeur » était caractérisé par un mode de plongée près de la surface et un deuxième mode à plus de 400 m de la surface. Le nombre moyen de plongées à l’heure variait de 5,1 (écart-type = 2,1) à 9,8 (écart-type = 2,9) pour ce qui est de tous les types de plongée, la catégorie des plongées en profondeur ayant enregistré le moins grand nombre de plongées. En général, la durée des plongées durait de 1 à 18 minutes, mais cela dit, certaines des plongées en profondeur ont duré jusqu’à 21 minutes. Nous avons trouvé peu d’indices portant à croire que le comportement de plongée des bélugas de notre échantillon variait en fonction du sexe ou de l’âge. De manière générale, les bélugas plongeaient plus en profondeur dans l’est de la mer de Beaufort que dans l’ouest de la mer de Beaufort ou dans la mer des Tchouktches. Les profondeurs auxquelles les bélugas plongent le plus souvent dans le canyon Barrow et le long du rebord continental de Beaufort (de 200 à 300 m) correspondent à la limite où l’eau plus froide du Pacifique se superpose à l’eau plus chaude de l’Atlantique, là où la morue polaire (Boreogadus saida) est plus dense. Dans le bassin arctique, la profondeur des plongées suggère que les bélugas s’alimentent surtout dans la couche tempérée d’eau de l’Atlantique (~200 à 1 000 m)

The Species Effect:Differential Sphingosine-1-Phosphate Responses in the Bone in Human Versus Mouse

he deterioration of osteoblast-led bone formation and the upregulation of osteoclast-regulated bone resorption are the primary causes of bone diseases, including osteoporosis. Numerous circulating factors play a role in bone homeostasis by regulating osteoblast and osteoclast activity, including the sphingolipid—sphingosine-1-phosphate (S1P). However, to date no comprehensive studies have investigated the impact of S1P activity on human and murine osteoblasts and osteoclasts. We observed species-specific responses to S1P in both osteoblasts and osteoclasts, where S1P stimulated human osteoblast mineralisation and reduced human pre-osteoclast differentiation and mineral resorption, thereby favouring bone formation. The opposite was true for murine osteoblasts and osteoclasts, resulting in more mineral resorption and less mineral deposition. Species-specific differences in osteoblast responses to S1P were potentially explained by differential expression of S1P receptor 1. By contrast, human and murine osteoclasts expressed comparable levels of S1P receptors but showed differential expression patterns of the two sphingosine kinase enzymes responsible for S1P production. Ultimately, we reveal that murine models may not accurately represent how human bone cells will respond to S1P, and thus are not a suitable model for exploring S1P physiology or potential therapeutic agents

Scrupulosity and Hoarding

Objective: Recent evidence suggests that avoiding waste may be a prominent motive to save in hoarding disorder. Such beliefs are reminiscent of scrupulosity obsessions in OCD. This paper reports on three studies examining scrupulosity-like beliefs in hoarding and the development and validation of a measure of material scrupulosity. Methods: Study one examined the reliability and validity of a measure of material scrupulosity (MOMS) and its relationship to hoarding in a college student sample, as well as the relationship between hoarding and OCD-base scrupulosity. Study 2 examined the psychometric properties of the MOMS in a replication of study 1 with a sample of people with hoarding problems. Study 3 examined the reliability and validity of the MOMS in a large nonclinical/community sample. Results: Findings across the studies provided evidence for the reliability and validity of the MOMS. It was highly correlated with hoarding symptoms, especially difficulty discarding, and hoarding related beliefs, especially responsibility beliefs. It accounted for significant variance in hoarding symptoms independent of other correlates, including other hoarding beliefs. OCD-based scrupulosity was correlated with hoarding in sample 1, but not in the hoarding sample in study 2. Conclusions: Material Scrupulosity refers to an exaggerated sense of duty or moral/ethical responsibility for the care and disposition of possessions to prevent their being harmed or wasted. It appears to be distinct from other hoarding-related beliefs and a significant predictor of hoarding symptoms. The MOMS appears to possess good reliability and validity in both clinical and nonclinical samples