Dispersal and behavior of Pacific halibut Hippoglossus stenolepis in the Bering Sea and Aleutian Islands region

Results of a coastwide tagging study show that ontogenetic migration of Pacific halibut (Hippoglossus stenolepis) continues for larger fish, whereas in recent years the assumption had been that only smaller, younger fish migrated. In 2003–2004, a total of 67 000 Pacific halibut tagged with passive integrated transponder tags were released by the International Pacific Halibut Commission (IPHC) from Oregon to the Bering Sea. Portside scanning recovered over 3000 of these tags. Models were fitted that allowed commercial fishing mortality to be a function of fish length, year, and IPHC regulatory area, while migration probability was a function of area and length. Estimates from the models support the view that exploitation rates were much higher in eastern than western areas prior to the reduction of quotas following new results from a coastwide stock assessment in 2007. We explore possible explanations for differences between tagging and IPHC stock assessment results and note that this research provides confirmation of historical inferences regarding patterns of halibut migration based on conventional tagging.

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Biochemical Population Genetics of Pacific Halibut (Hippoglossus stenolepis) and Comparison with Atlantic Halibut (H. hippoglossus)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f84-127 ◽

1984 ◽

Vol 41 (7) ◽

pp. 1083-1088 ◽

Cited By ~ 53

Author(s):

W. Stewart Grant ◽

David J. Teel ◽

Tokimasa Kobayashi ◽

Cyreis Schmitt

Keyword(s):

Genetic Distance ◽

Bering Sea ◽

Gene Diversity ◽

Gulf Of Alaska ◽

Atlantic Halibut ◽

Protein Coding ◽

Pacific Halibut ◽

Three Samples ◽

Hippoglossus Stenolepis ◽

The Bering Sea

The gene products of 35 protein-coding loci were examined for Mendelian variation in three samples of Pacific halibut (Hippoglossus stenolepis) and one sample of Atlantic halibut (H. hippoglossus). Contingency table analyses of allelic frequencies for five polymorphic loci revealed no significant frequency differences between the Bering Sea and the Gulf of Alaska but detected significant Ada-2 frequency differences between these regions and Japan. Average genetic distance between the samples of Pacific halibut was 0.0002 ± 0.0007, and gene diversity analyses showed that 98.7% of the total genetic variation was contained within populations, 0.4% was due to differences between the Bering Sea and the Gulf of Alaska, and 0.9% was due to differences between these regions and Japan. These results are consistent with a larval drift, juvenile migration model of population genetic structure where not all juveniles home to their natal areas. Nei's genetic distance between Pacific and Atlantic halibut was 0.162 ± 0.073, and the molecular clock hypothesis suggests that these species became reproductively isolated from one another in the Pliocene between 1.7 and 4.5 million years ago.

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A mixed-species yield model for eastern Bering Sea shelf flatfish fisheries

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f02-012 ◽

2002 ◽

Vol 59 (2) ◽

pp. 291-302 ◽

Cited By ~ 8

Author(s):

Paul D Spencer ◽

Thomas K Wilderbuer ◽

Chang Ik Zhang

Keyword(s):

Bering Sea ◽

Optimal Solution ◽

Single Species ◽

Mixed Species ◽

Yield Model ◽

Pacific Halibut ◽

Eastern Bering Sea ◽

Hippoglossus Stenolepis ◽

Hippoglossoides Elassodon ◽

Trawl Fisheries

A variety of eastern Bering Sea (EBS) flatfish including yellowfin sole (Limanda aspera), rock sole (Lepidopsetta bilineata), flathead sole (Hippoglossoides elassodon), and Alaska plaice (Pleuronectes quadrituberculatus), co-occur in various degrees in EBS trawl fisheries, impeding attempts to obtain single-species management targets. A further complication is the bycatch of Pacific halibut (Hippoglossus stenolepis); halibut bycatch limits, rather than single-species catch quotas, have been the primary factor regulating EBS flatfish harvest in recent years. To examine bycatch interactions among the EBS flatfish listed above, an equilibrium mixed-species multifishery model was developed. Equilibrium yield curves, scaled by recent average recruitment, are flat topped or asymptotically increasing, reflecting low fishing selectivity during the first several years of life and low growth relative to natural mortality. A linear programming analysis indicated that relaxation of the halibut bycatch constraint at the optimal solution of catch by fishery would produce approximately 20 times more flatfish yield than a similar relaxation of any flatfish catch quota. A strategy for establishing halibut bycatch limits that considers the foregone revenue in the halibut and flatfish trawl fisheries reveals how the choice of halibut bycatch limit is affected by the management goal for the flatfish complex.

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Modeling connectivity of walleye pollock in the Gulf of Alaska: Are there any linkages to the Bering Sea and Aleutian Islands?

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2015.12.010 ◽

2016 ◽

Vol 132 ◽

pp. 227-239 ◽

Cited By ~ 15

Author(s):

Carolina Parada ◽

Sarah Hinckley ◽

John Horne ◽

Michael Mazur ◽

Albert Hermann ◽

...

Keyword(s):

Bering Sea ◽

Gulf Of Alaska ◽

Walleye Pollock ◽

Aleutian Islands ◽

The Bering Sea

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Distribution and movements of white foxes in northern and western Alaska

Canadian Journal of Zoology ◽

10.1139/z68-121 ◽

1968 ◽

Vol 46 (5) ◽

pp. 849-854 ◽

Cited By ~ 12

Author(s):

David L. Chesemore

Keyword(s):

Sea Ice ◽

Bering Sea ◽

Early Spring ◽

Aleutian Islands ◽

Late Winter ◽

Seasonal Movements ◽

Alaskan Arctic ◽

Northern Alaska ◽

The Bering Sea

White foxes occur on the tundra of northern and western Alaska and predominate on St. Lawrence, St. Matthew, Hall, and Diomede Islands in the Bering Sea. Few white foxes are found on the Pribilof and Aleutian Islands where blue foxes dominate the local fox population. On the Alaskan Arctic Slope, two seasonal movements, the first in the fall when foxes move seaward towards the coast and sea ice, and the second in late winter and early spring when they return inland to occupy summer den sites, occur. Although reported in other arctic areas, no definite records of fox migrations in northern Alaska exist. Distribution records for white foxes in Alaska are summarized.

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STATE OF STOCKS AND MODERN FISHERY OF ATKA MACKEREL PLEUROGRAMMUS MONOPTERYGIUS (PALLAS, 1810) IN THE OLYUTORSKY-NAVARINSKY AREA OF THE BERING SEA

Izvestiya TINRO ◽

10.26428/1606-9919-2020-200-38-57 ◽

2020 ◽

Vol 200 ◽

pp. 38-57

Author(s):

A. O. Zolotov ◽

O. G. Zolotov ◽

Yu. K. Kurbanov

Keyword(s):

Bering Sea ◽

Gulf Of Alaska ◽

Aleutian Islands ◽

Commander Islands ◽

Spawning Grounds ◽

Spawning Stock ◽

Atka Mackerel ◽

Pleurogrammus Monopterygius ◽

Commercial Stock ◽

The Bering Sea

Atka mackerel Pleurogrammus monopterygius is one of the mass species of fam. Hexagrammidae that inhabits the boreal and subarctic waters of the North Pacific and forms two large populations in its western and eastern parts. Reproductive range of the eastern, Aleutian population extends from the Gulf of Alaska, along Aleutian Islands to Commander Islands, with the main spawning grounds at the Aleutians and in the southeastern Bering Sea. From these areas, the fish at early stages of ontogenesis spread widely in system of the Bering Sea currents to the western-southwestern Bering Sea, where the atka mackerel aggregations are formed on the external shelf at prominent capes, as Cape Olyutorsky. Dynamics of the atka mackerel stock in the Olyutorsky-Navarinsky area in 1994–2019 is presented on the base of bottom trawl surveys, fishery statistics, and open NOAA data. After the period of low stock in the middle 1990s, the atka mackerel abundance increased sharply to the maximum in 2006–2008, when the spawning stock in this area was about 9.5 . 103 t and the commercial stock about 14.0 . 103 t. Since that time, trend to decreasing is observed, with the spawning stock 3.6 . 103 t and the commercial stock 5.6 . 103 t in 2013, and recent stabilization at the low level with slight decline continuing. A possible reason of the sharp increase in 2000s could be the intensive transport of the atka mackerel juveniles from the main spawning grounds at Aleutian Islands to the area at Cape Olyutorsky. The catches of atka mackerel in the Olyutorsky-Navarinsky area in 1994–2018 corresponded well with its stock dynamics.

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