Middle Pleistocene Mollusks from St. Lawrence Island and their Significance for the Paleo-Oceanography of the Bering Sea

Drift, evidently of Illinoian age, was deposited on St. Lawrence Island at the margin of an ice cap that covered the highlands of the Chukotka Peninsula of Siberia and spread far eastward on the continental shelf of northern Bering Sea. Underlying the drift on the northwestward part of the island are mollusk-bearing beds deposited during the Kotzebuan Transgression. A comparison of mollusk faunas from St. Lawrence Island, Chukotka Peninsula, and Kotzebue Sound suggests that the present northward flow through Bering and Anadyr Straits was reversed during the Kotzebuan Transgression. Cold arctic water penetrated southward and southwestward bringing an arctic fauna to the Gulf of Anadyr. Warmer Pacific water probably entered eastern Bering Sea, passed eastward and northeastward around eastern and northern St. Lawrence Island, and then became entrained in the southward currents that passed through Anadyr Strait.

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Lycodapus (Pisces: Zoarcidae) of eastern Bering Sea and nearby Pacific Ocean, with three new species and a revised key to the species

Canadian Journal of Zoology ◽

10.1139/z81-096 ◽

1981 ◽

Vol 59 (4) ◽

pp. 667-678 ◽

Cited By ~ 5

Author(s):

Alex E. Peden ◽

M. Eric Anderson

Keyword(s):

New Species ◽

Pacific Ocean ◽

Bering Sea ◽

Sea Of Okhotsk ◽

Range Limit ◽

The Sea Of Okhotsk ◽

Eastern Bering Sea ◽

Northern Range Limit ◽

Three New Species ◽

The Bering Sea

Lycodapus leptus n.sp., L. poecilus n.sp., and L. psarostomatus n.sp. are described from the eastern Bering Sea. A new key to all known species of Lycodapus is presented. In addition, L. fierasfer Gilbert, L. parviceps Gilbert, and L. derjugini Andriashev are recognized from the Bering Sea and L. microdon Schmidt is recognized from the Sea of Okhotsk. The northern range limit of Lycodapus dermatinus Gilbert is established from a sea mount off southeastern Alaska. A specimen of Lycodapus that cannot be identified to species represents the most southern record for the genus in Asiatic waters.

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Application of a sequential regime shift detection method to the Bering Sea ecosystem

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2005.01.013 ◽

2005 ◽

Vol 62 (3) ◽

pp. 328-332 ◽

Cited By ~ 188

Author(s):

Sergei Rodionov ◽

James E. Overland

Keyword(s):

Bering Sea ◽

Regime Shift ◽

Poor Performance ◽

Regime Shifts ◽

Test Analysis ◽

Eastern Bering Sea ◽

Time Signals ◽

Shift Detection ◽

Changes Over Time ◽

The Bering Sea

Abstract A common problem of existing methods for regime shift detection is their poor performance at the ends of time-series. Consequently, shifts in environmental and biological indices are usually detected long after their actual appearance. A recently introduced method based on sequential t-test analysis of regime shifts (STARS) treats all incoming data in real time, signals the possibility of a regime shift as soon as possible, then monitors how perception of the magnitude of the shift changes over time. Results of a STARS application to the eastern Bering Sea ecosystem show how the 1989 and 1998 regime shifts manifest themselves in biotic and abiotic indices in comparison with the 1977 shift.

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Age, growth, and maturity of the whitebrow skate, Bathyraja minispinosa, from the eastern Bering Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsr072 ◽

2011 ◽

Vol 68 (7) ◽

pp. 1426-1434 ◽

Cited By ~ 21

Author(s):

Shaara M. Ainsley ◽

David A. Ebert ◽

Gregor M. Cailliet

Keyword(s):

Bering Sea ◽

Growth Models ◽

Gompertz Model ◽

Parameter Estimates ◽

Population Declines ◽

Age At Maturity ◽

Von Bertalanffy Model ◽

Eastern Bering Sea ◽

Best Fit ◽

The Bering Sea

Abstract Ainsley, S. M., Ebert, D. A., and Cailliet, G. M. 2011. Age, growth, and maturity of the whitebrow skate, Bathyraja minispinosa, from the eastern Bering Sea. – ICES Journal of Marine Science, 68: 1426–1434. Skates are a common bycatch in groundfish fisheries in the Bering Sea; however, their life-history characteristics are not well known. The study is the first to investigate the age, growth, and age at maturity of Bathyraja minispinosa. Ages were estimated using sectioned vertebrae and several growth models were compared. The Gompertz model was the best fit and no significant differences were detected between sexes for any model. The maximum age estimated was 37 years, and parameter estimates generated from the three-parameter von Bertalanffy model were k = 0.02 year−1 and L∞ = 146.9 cm total length (TL). Males reached their size at 50% maturity larger than females (70.1 and 67.4 cm, respectively), but no significant differences in the estimated size or age at maturity were found. Whereas B. minispinosa is smaller than many skate species in the eastern Bering Sea, it has a considerably longer estimated lifespan, indicating that size may not be a reliable method of estimating the vulnerability of a rajid species to population declines in the eastern North Pacific.

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Individual and colony-specific wintering areas of Pacific northern fulmars (Fulmarus glacialis)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f09-184 ◽

2010 ◽

Vol 67 (2) ◽

pp. 386-400 ◽

Cited By ~ 22

Author(s):

Scott A. Hatch ◽

Verena A. Gill ◽

Daniel M. Mulcahy

Keyword(s):

Bering Sea ◽

Gulf Of Alaska ◽

Fulmarus Glacialis ◽

Northern Bering Sea ◽

Eastern Bering Sea ◽

Deep Waters ◽

Pribilof Island ◽

Wintering Areas ◽

Satellite Transmitters ◽

Northern Fulmars

Seabird mortality associated with longline fishing in the eastern Bering Sea occurs mainly from September to May, with northern fulmars ( Fulmarus glacialis ) comprising the majority (60%) of the bycatch. Along the west coast of North America, winter dieoffs of fulmars may be increasing in frequency and magnitude, the most severe on record being a wreck that peaked in October–November 2003. We deployed satellite transmitters on fulmars from the four main Alaska colonies and tracked individuals for up to 2 years. Fulmars from Hall Island (northern Bering Sea) moved to Russian coastal waters after breeding, while Pribilof Island fulmars (southeastern Bering Sea) remained relatively sedentary year-round. Birds from Chagulak Island (eastern Aleutians) preferred passes between the Aleutian Islands in winter or foraged widely over deep waters of the central Bering Sea and North Pacific. Fulmars from the Semidi Islands (western Gulf of Alaska) migrated directly to waters of the California Current. Individuals from St. George Island (Pribilofs) and Chagulak were consistent in the places that they visited in two successive winters. The Pribilof Islands population is most affected by winter longlining for groundfish, whereas the Semidi Islands colony sustains most of the natural mortality that occurs off Washington, Oregon, and California.

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Role of physical processes in formation of spring phytoplankton bloom in the Bering Sea

Trudy VNIRO ◽

10.36038/2307-3497-2020-181-206-222 ◽

2020 ◽

Vol 181 ◽

pp. 206-222

Author(s):

K.K. Kivva ◽

◽

J.V. Selivanova ◽

M.N. Pisareva ◽

A.A. Sumkina ◽

...

Keyword(s):

Bering Sea ◽

Phytoplankton Bloom ◽

Physical Processes ◽

Spring Phytoplankton Bloom ◽

Eastern Bering Sea ◽

Ice Retreat ◽

Shelf Region ◽

Sea Ice Retreat ◽

Bering Sea Shelf ◽

The Bering Sea

The main part of the annual primary production in the Arctic and Subarctic zones of the World Ocean is formed during the spring phytoplankton bloom. The timing of the bloom depends on combination of physical factors. Oscillating control hypothesis, proposed in [Hunt et al., 2002] for the Eastern Bering Sea, describes annual peculiarities of ecosystem development related to conditions of the spring phytoplankton bloom. We review propositions of this hypothesis on the reasons of phytoplankton bloom and its connection with physical processes for four local regions of the Bering Sea shelf. The regions include western, northern and south-eastern parts of the shelf. The analysis is based on ocean color and microwave remotely sensed data as well as on atmospheric reanalysis. The results allow for hypothesis improvement. An early phytoplankton bloom may be present in the surface layer in April or May along the eastern Bering Sea shelf even in situations of early sea ice retreat (e. g. February-March) or absence of ice during winter. However, such combinations were not observed in the western Bering Sea shelf region. In 1998–2018, early ice retreat in the western shelf region was always accompanied by relatively late phytoplankton bloom. The temporal lag between sea ice retreat and phytoplankton bloom may be substantial in some years along the southernmost position of the ice edge. On the other hand, the spring bloom in the northern part of the shelf usually follows the ice retreat. In case of early ice retreat, the timing of the bloom is determined not only by wind conditions, but also by heat balance at the surface of the sea. The results are proposed to be used in further analysis of ecosystem dynamics of the western Bering Sea shelf.

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Why does the pollock (Theragra chalcogramma) abundance change

Izvestiya TINRO ◽

10.26428/1606-9919-2016-185-31-48 ◽

2016 ◽

Vol 185 (2) ◽

pp. 31-48

Author(s):

Vyacheslav P. Shuntov

Keyword(s):

Bering Sea ◽

Food Supply ◽

Global Changes ◽

Winter Mortality ◽

Migration Timing ◽

Northern Bering Sea ◽

Class Strength ◽

Strength Dependence ◽

The Bering Sea

Some common ideas about environmental factors that determine the patterns of migration (including timing) and stock dynamics of walleye pollock are critically analyzed with particular attention to the Bering Sea. There is shown that the conception of the migration timing dependence on food supply in the northern Bering Sea does not represent the real facts, as well as the conception of year-class strength dependence on winter mortality of fingerlings determined by food supply, especially in conditions of its deficiency. Periodicity of the pollock stocks dynamics associated with global changes of climatic and oceanographic factors is also called in question. Role of provincial factors in dynamics of the pollock populations is discussed and emphasized.

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Contrasting the variability in spatial distribution of two juvenile flatfishes in relation to thermal stanzas in the eastern Bering Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz180 ◽

2019 ◽

Vol 77 (3) ◽

pp. 953-963

Author(s):

Cynthia Yeung ◽

Daniel W Cooper

Keyword(s):

Spatial Distribution ◽

Bering Sea ◽

Thermal Environment ◽

Bottom Temperature ◽

Eastern Bering Sea ◽

Northward Expansion ◽

Yellowfin Sole ◽

Temperature Indices ◽

Limanda Aspera ◽

The Bering Sea

Abstract Groundfish species in the Bering Sea are undergoing pronounced changes in spatial distribution and abundance due to warming ocean temperatures. The main drivers of interannual variability in this ecosystem are the alternating warm and cold thermal stanzas. Yellowfin sole (Limanda aspera; YFS) and northern rock sole (Lepidopsetta polyxystra; NRS) are commercially-valuable flatfishes in the Bering Sea and are among the most dominant groundfish species there in numbers and biomass. We examined the variability in the spatial distribution and abundance of juvenile NRS and YFS in relation to the ice and temperature conditions associated with warm-cold thermal shifts from 1982 to 2017. The goal was to assess the implications of the fluctuating thermal environment for Bering Sea flatfish production. We found ice cover and bottom temperature indices in the preceding 1 to 3 years to be the best predictors of NRS juvenile distribution. In contrast, these indices were not significantly correlated with YFS juvenile distribution, which could be an artifact of their relatively low availability to sampling. A warm stanza, as the Bering Sea is currently in, is expected to favor high numbers of NRS juveniles and the northward expansion of their distribution.

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Distributional patterns of 0-group Pacific cod (Gadus macrocephalus) in the eastern Bering Sea under variable recruitment and thermal conditions

ICES Journal of Marine Science ◽

10.1093/icesjms/fss011 ◽

2012 ◽

Vol 69 (2) ◽

pp. 163-174 ◽

Cited By ~ 13

Author(s):

Thomas P. Hurst ◽

Jamal H. Moss ◽

Jessica A. Miller

Keyword(s):

Bering Sea ◽

Thermal Conditions ◽

Pacific Cod ◽

Eastern Bering Sea ◽

Pacific Cod Gadus Macrocephalus ◽

Gadus Macrocephalus ◽

Basin Scale ◽

Distributional Patterns ◽

Variable Recruitment ◽

The Bering Sea

Abstract Hurst, T. P., Moss, J. H., and Miller, J. A. 2012. Distributional patterns of 0-group Pacific cod (Gadus macrocephalus) in the eastern Bering Sea under variable recruitment and thermal conditions. – ICES Journal of Marine Science, 69: 163–174. Despite the importance of Pacific cod in Bering Sea fisheries and foodwebs, little is known about the habitat use and the distribution of early life stages. We analysed 6 years of catch data for 0-group Pacific cod in fishery-independent surveys of the Bering Sea shelf. Juvenile cod were most commonly captured on the middle shelf over depths of 50–80 m and were rarely captured north of 58°N. Consistently high catches were observed east of the Pribilof Islands and north of Port Moller along the Alaska Peninsula. There was evidence of density-dependent habitat selection at the local scale as the frequency of occurrence increased with regional catch per unit effort. At the basin scale, the southerly distribution of the weak 2009 cohort suggested the possibility of a range contraction for small cohorts. There was no consistent shift in the distribution of juvenile Pacific cod in response to interannual climate variability. These results for Pacific cod contrast with those observed for walleye pollock, which appears to exhibit greater variance in distribution, but are similar to patterns observed for juvenile Atlantic cod. Future work should focus on distribution in nearshore habitats and examine the patterns of dispersal and the connectivity of the Bering Sea and Gulf of Alaska populations.

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Gray whale feeding on dense ampeliscid amphipod communities near Bamfield, British Columbia

Canadian Journal of Zoology ◽

10.1139/z84-009 ◽

1984 ◽

Vol 62 (1) ◽

pp. 41-49 ◽

Cited By ~ 35

Author(s):

John S. Oliver ◽

Peter N. Slattery ◽

Mark A. Silberstein ◽

Edmund F. O'Connor

Keyword(s):

Bering Sea ◽

Benthic Communities ◽

Gray Whale ◽

Gray Whales ◽

Northern Bering Sea ◽

Amphipod Crustacean ◽

Different Parts ◽

Feeding Grounds ◽

Made In ◽

The Bering Sea

Gray whales fed on dense populations of ampeliscid amphipods while summering along the west coast of Vancouver Island. These amphipod crustacean communities are ecological analogs of the primary feeding grounds of gray whales in the northern Bering Sea. The same major genera of amphipods dominated the Alaskan and Canadian feeding grounds, including Ampelisca, Photis, Protomedeia, Anonyx, and Orchomene, and comprised 67 to 90% of the number of infaunal crustaceans at the two locations. This is the first documented report of gray whale feeding on benthic infauna south of the Bering Sea. Feeding gray whales observed in Pachena Bay produced an extensive record of feeding excavations in bottom sediments. Excavation patterns suggest that: (i) whales used suction to extract infaunal prey and sediments; (ii) a maximum of six excavations was made in one feeding dive; (iii) excavation size was related to whale size; (iv) small and large whales fed in different parts of the bay; and (v) whales effectively located and worked the densest patches of benthic prey. We estimate that a 6-m whale consumed 116 kg of infaunal prey per 12-h day, and that a 12-m whale consumed 552 kg per 12-h day. Scavenging lysianassid amphipods were attracted to feeding disturbances within seconds and preyed on injured and dislodged infauna. Individual feeding excavations were large, deep valleys in a tube-mat plateau. In addition to the lysianassids, many other infauna undoubtedly colonize these highly modified habitats, resulting in important effects on the structure of benthic communities.

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State of forage base for pacific salmons in the Bering Sea in 2003-2012 (by results of surveys of the international expeditions BASIS-1 and 2)

Izvestiya TINRO ◽

10.26428/1606-9919-2014-179-250-271 ◽

2014 ◽

Vol 179 (4) ◽

pp. 250-271

Author(s):

Anatoly F. Volkov

Keyword(s):

Bering Sea ◽

Regime Shift ◽

Pacific Salmon ◽

Zooplankton Community ◽

Demersal Fish ◽

Large Species ◽

Sand Lance ◽

Eastern Bering Sea ◽

The Bering Sea

The BASIS expeditions in the Bering Sea were conducted by North Pacific Anadromous Fish Comission (NPAFC) in the 2003-2006 and 2007-2012, in relatively warm and relatively cold conditions, respectively. The ice cover of the Sea changed synchronously in its western and eastern parts and indicated the warm regime since 2001 to 2006 and the cold regime since 2006 till nowadays. The regime shift changed radically the structure of zooplankton community in the eastern Bering Sea: the dominance of small-sized and medium-sized zooplankton was replaced by the dominance of large-sized zooplankton, with abundant large species of euphausiids, hyperiids, copepods, and arrowworms. This restructuring was reflected in the diet of pacific salmon: the bulk of the pink, chum and sockeye salmons diet was presented by fingerlings of pollock, sand lance, and capelin, larvae of flounders and crabs, and fry of small demersal fish in 2003-2006, but by zooplankton as euphausiids, hyperiids, and pteropods since 2007. However, there weren’t so essential changes in the western Bering Sea, both in zooplankton structure and salmons diet; the year-to-year dynamics was significant here, too, but long-term tendencies were not observed.

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