Northern Kuril Islands Research Articles

On the diet of the rock sole Lepidopsetta polyxystra off the eastern coast of the northern Kuril Islands and the southern extremity of Kamchatka

The bulk of diet of the rock sole Lepidopsetta polyxystra in waters of the eastern coast of the northern Kuril Islands and the southern extremity of Kamchatka from September to October 1997 was formed by polychaetes and amphipods (36.8 and 35.1% of the food bolus weight, respectively), which is typical of the feeding of this species, on the whole. The dominant consumption by L. polyxystra of polychaetes is recorded from February to June and of amphipods, from August to December. Polychaetes dominated in the diet of individuals with a length of 16–45 cm and amphipods, in the diet of individuals 46–55 cm long. The feeding migration of L. polyxystra in the study area took place at sites with an increased biomass of the accessible food benthos.

Some issues related to reproduction of Pacific cod Gadus macrocephalus in waters of the eastern coast of the northern Kuril Islands and the southern extremity of Kamchatka

The analysis of data collected in December 1996 and 1998 on the reproduction of cod Gadus macrocephalus in Pacific waters of the northern Kuril Islands and the southern part of Kamchatka was performed. It was shown that the individual absolute fecundity of the cod varies within 0.197–9.729 million eggs and the relative fecundity, in the range of 24-1386 eggs. The fecundity of 1000 mature females comprises 2179–2449 million eggs. The low individual fecundity of fish is related to pseudobranchial tumor growth. The main role in cod reproduction is played by females of two-three size groups characterized by the highest numbers of mature females. It is suggested that different fecundity within the range of Pacific cod is related to environmental conditions, in particular, water temperature in the spawning grounds during spawning rather than to the habitation latitude.

Specific features of distribution and ecology of the Japanese dog poacher Percis japonica (Agonidae) in Pacific waters off the northern Kuril Islands and southeastern Kamchatka

According to materials of 1992–2002, data on the spatial-bathymetric distribution and size composition of the Japanese dog poacher Percis japonica in Pacific waters off the northern Kuril Islands and southeastern Kamchatka are provided. This comparatively scarce, medium-sized representative of the family Agonidae (maximum length of 46 cm) in the observation period was found in the lower part of the shelf and the upper bathyal over the entire study area from 47°50′ to 52°00′ N at depths of 76–770 m; however, its maximum catches (more than 200 individuals per hour of trawling) were constantly recorded in the spring and autumn months at the traverse of the Fourth Kuril Strait and at the eastern slope of the seamount of the northern link of the external Kuril Ridge, mainly in the range of 251–350 m at a temperature of 1.6–3.0°C. The relationship between the depth of catch and the average weight of P. japonica was analyzed. It was shown that the value of its catches in Pacific waters off the northern Kuril Islands and southeastern Kamchatka is subjected to some interannual, seasonal, and diurnal dynamics.

Specific features of distribution, some features of biology, and the dynamics of catches of smooth lumpsucker Aptocyclus ventricosus (Cyclopteridae) in waters of the Pacific Ocean off the Kuril Islands and Kamchatka

On the basis of data on bottom trawl catches in Pacific waters off the northern Kuril Islands and southeastern Kamchatka (1992–2002), quantitative indices of occurrence of the smooth lumpsucker Aptocyclus ventricosus and the range of preferred habitation temperature are provided. Its spatial and vertical distribution are analyzed, and specific features of size composition and the relationship between the length and weight of the body and between the average weight and the capture depth are considered; the diurnal, seasonal, and long-term dynamics of occurrence and of the amount of average catches is presented; data on the species composition of fish present in catches parallel to A. ventricosus are cited.

Comparative characteristics of the diet of Pacific halibut Hippoglossus stenolepis from different areas of the northwestern part of the Pacific Ocean

Food composition of Pacific halibut Hippoglossus stenolepis has been considered in three areas of the northwestern Pacific: in the western part of the Bering Sea, in Pacific waters off the northern Kuril Islands and southeastern Kamchatka, and waters off the southern Kuril Islands. The main food items in all studied regions were shrimp, cephalopods, and fish. It has been noted that fish offal plays a considerable role in the feeding of H. stenolepis in the western part of the Bering Sea. Changes in food composition in relation to fish growth, depth of catch, and sex of individuals have been analyzed; and differences in the composition of food items consumed by H. stenolepis in different parts of the studied areas have been considered.

Specific features of spatial distribution of Pacific cod Gadus macrocephalus in waters off the eastern coast of the northern Kuril Islands and the southern extremity of Kamchatka

Spatial distribution of Pacific cod Gadus macrocephalus inhabiting waters off the eastern coast of the northern Kuril Islands and the southern part of Kamchatka has been studied. It is shown that the redistributions of densities of the aggregation of cod during the year occur mainly within the area under consideration. The absence of considerable migrations of cod is related, in particular, to sufficient food availability of abundant hydrobionts: for small-sized groups of cod, the main food are juvenile wall-eyed pollack Theragra chalcogramma and, for medium-sized and large-sized groups, its adult individuals and also Atka mackerel Pleurogrammus monopterygius and squid Belonella borealis.

Radiocarbon Dating of Large Holocene Volcanic Events Within South Kamchatka (Russian Far East)

Radiocarbon dating is widely used when studying recent volcanic activity in the Kamchatka Peninsula due to the abundance of organic matter that is associated with the volcanic deposits. Here, we present the results of 14C dating of major volcanic events within the active South Kamchatka volcanic zone. South Kamchatka includes 8 recently active volcanic centers (stratovolcanoes, calderas, and large craters) that have been erupting during the Holocene. Their tephras represent useful markers for both the southern part of the peninsula and the Northern Kurile Islands. Since these marker tephra layers facilitate stratigraphic and tephrochronological studies in this area, it was important to determine their ages. We have obtained 73 new individual 14C dates on paleosol, peat, charcoal, and wood associated with the marker tephra layers, then complemented these data with 37 earlier published dates and analyzed the resulting data set. We selected the reliable dates and then obtained average 14C ages of marker tephra layers. The details of these procedures, as well as brief descriptions of South Kamchatka Holocene eruptions and their tephra beds, are presented in the paper.

Biological features of the sea raven Hemitripterus villosus (Hemitripteridae) in Pacific waters off the northern Kuril Islands and southeastern Kamchatka

Data on the spatial-bathymetric distribution and the size-weight composition of the sea raven Hemitripterus villosus in Pacific waters off the northern Kuril Islands and southeastern Kamchatka are provided. This representative of the family Hemitripteridae is a comparatively scarce, large fish species (maximum length 75 cm, body weight 11.8 kg), which in the study period (1992–2002) was found practically everywhere at the site from 48°00′ to 52°00′ N in the depth interval of 83–496 m at near-bottom temperatures from −1.2 to 3.5°C. However, during the year, the overwhelming majority of its individuals were recorded in two depth ranges—101–150 and 251–400 m, which is accounted for by seasonal changes in the habitation depths. With an increase in depth, the sizes of H. villosus increase in catches due to the fact that individuals with a body weight smaller than 1.7–1.9 kg reside mainly at depths of up to 300 m, and those with a body weight greater than 2.2–3.0 kg reside at larger depths. It is demonstrated that the occurrence and the amount of catches of H. villosus are subjected to some interannual, seasonal, and diurnal dynamics.

Size and age composition of populations and growth of Mytilus trossulus (Bivalvia: Mytilidae) in the subtidal area of western Kamchatka

Fairly large Mytilus trossulus beds were found in the subtidal zone at depths to 40 m off the western coast of Kamchatka. The size and age composition of local populations and growth rates of M. trossulus in this region and at Atlasova Island were studied. Significant variability of the shell shape of mollusks was found. In the western Kamchatka subtidal, M. trossulus grew faster than in the northern Kuril Islands and eastern Kamchatka. Mussels attained commercial size (50 mm in shell length) in the fourth year of life in the former case and in the fifth-sixth year in other cases. Mollusks of different ages, from 1 to 8–9 year olds, were present in western Kamchatka populations; i.e., juvenile recruitment takes place regularly, while growth rates vary. Growth and population structure of M. trossulus are discussed in relation to the habitat conditions on the western Kamchatka shelf.

Spatial distribution and dynamics of catches of Sebastes glaucus, S. iracundus, and S. polyspinis in Pacific waters off the Kuril Islands and Kamchatka

Based on studies of the years 1992–2001, quantitative indices characterizing the occurrence of three rare or little-studied species of rockfish (Sebastes glaucus, S. iracundus, and S. polyspinis) in Pacific waters off the northern Kuril Islands and southeastern Kamchatka are provided. Specific features of distribution (spatial, vertical, and dependence on near-bottom temperatures) are considered. New data on the diurnal, seasonal, and multiyear dynamics of their catches and occurrence, as well as on the length and weight of the body, sex ratio, and sexual dimorphism in the amount and intensity of feeding are cited.

Bryophytes of northern Kuril Islands (north-west Pacific)

Bryophytes of northern Kuril Islands (north-west Pacific)

Preseismic anomaly of LF signal on the wave path Japan–Kamchatka during November–December 2004

The variations of phase and amplitude of LF signal propagating from the transmitter JJY (40 kHz, Fukushima prefecture, Japan) are analyzed. The receiver is situated in Petropavlovsk-Kamchatski (Russia). The time interval from July1, 2004 till January 24, 2005 is included in the examination. This interval is characterized by quiet seismic conditions up to the beginning of November, but rather strong seismic activity occurs in November and December not far from Hokkaido (Japan) and in the region of northern Kuril Islands. Seismic activity in a zone of sensitivity of our wave paths is determined by three series of earthquakes with M = 5.6–7.1. Nighttime “bay-like” phase and amplitude anomalies of the LF signal begin some days before the first earthquake and continue till the last earthquake of this series ( M = 6.2, November 11, 2004). Most strong and obvious anomalies appear in the amplitude of the LF signal. After that, during about one fortnight a period of seismic calm is observed. Then there is a following anomaly of the LF signal before two earthquakes ( M = 7.1, 28.11.04 and M = 6.8, 6.12.04). The next LF anomaly is observed before the earthquakes on December, 18 and 21 ( M = 5.8 and M = 5.6). During the whole period of seismic activity a significant shift in terminator times is also evident. The spectrum of LF seismo-induced anomalies shows a clear increase for the periods of 10–25 min.

Distribution and traits of the biology of roughskin sculpin Rastrinus scutiger (cottidae) in the pacific waters of the Northern Kuril Islands

Distribution and traits of the biology of roughskin sculpin Rastrinus scutiger (cottidae) in the pacific waters of the Northern Kuril Islands

ASTER observations of thermal anomalies preceding the April 2003 eruption of Chikurachki volcano, Kurile Islands, Russia

Chikurachki volcano (Northern Kurile Islands Chain, Paramushir Island 50° 20′N, 155° 27′E; elevation 1816 m, stratovolcano) has been in a state of unrest for over twenty years. Its most recent eruption that began in April 2003 was preceded by an eruption between January and May 2002. Thermal infrared images from the Japanese–United States' Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER-5 TIR channels, 8–12 μm, 90 m/pixel, Noise Equivalent Delta Temperature [NEΔT] ∼0.1–0.3 K; onboard the U.S. National Aeronautics and Space Administration's Terra polar-orbiting spacecraft) of a snow-covered Chikurachki Volcano taken in January 2003 show muted evidence of thermal activity. ASTER thermal infrared (TIR) images from February 2003, however, indicate warmer areas within the summit crater. Average whole-pixel temperatures of adjacent summit slopes are in the range of 250–252 K, while many summit-crater whole pixel temperatures are ∼2–6 K greater. A two component Planck solution for the warmer pixels yields a solution of 275–277 K for 10–15% of the Chikurachki summit crater and 285–295 K for 25–35% of a prominent “hotspot” on its flank. An interpretation of this enhanced pre-eruption heat flow is the presence of surface melt water. The detection in ASTER data of such subtle precursory heat-flow enhancement, even retrospectively, raises important issues for remote monitoring of “dormant” snow-capped volcanoes, especially those that threaten nearby populations, like Mt. Rainier.

Anomalies of LF signal during seismic activity in November–December 2004

Abstract. A signal transmitted by Japan Time Standard LF station (40 kHz, Fukushima prefecture) and recorded in Petropavlovsk-Kamchatski (Russia) is analyzed during a time interval from 1 July 2004 till 24 January 2005. This interval is characterized by quiet seismic conditions up to the beginning of November, but rather strong seismic activity occurs in November and December not far from Hokkaido (Japan) and in the region of northern Kuril Islands. There were three series of earthquakes with M=5.6–7.1 in a zone of sensitivity of our wave path during two months. Nighttime "bay-like" phase and amplitude anomalies of the LF signal are observed several days before and during every series of earthquakes. During the whole period of seismic activity a significant shift in terminator times is also evident. The spectrum of LF seismo-induced anomalies shows a clear increase for the period of about 25 min.

Trophic Interrelations in Predatory Fishes of Pacific Waters Circumambient the Northern Kuril Islands and Southeastern Kamchatka

Trophic Interrelations in Predatory Fishes of Pacific Waters Circumambient the Northern Kuril Islands and Southeastern Kamchatka

Feeding of the Snailfish Careproctus cf. cyclocephalusin Pacific Waters of the Northern Kuril Islands

This paper describes the feeding habits of the snailfish Careproctus cf. cyclocephalus (Scorpaeniformes, Liparidae). The diet consisted mostly of crustaceans, among which decapods predominated comprising up to 69.3% of the mean biomass of food organisms. Small shrimp (Eualus biunguis and E. townsendi) dominated the diet making up over 40.9% of the total stomach fullness index.

Feeding of the Snailfish Careproctus roseofuscus in Pacific Waters of the Northern Kuril Islands and Southeastern Kamchatka

The paper describes the feeding of two phenotypically different forms of the snailfish Careproctus roseofuscus (Scorpaeniformes, Liparidae) from the Pacific waters of the northern Kuril Islands and southeastern Kamchatka. The diet in the first form is comprised of actiniae. The second form mostly feeds on fish eggs and the amphipod Metopa majuscula Gurjanova. The second form is supposed to be confined to the biocenosis of Ophiopholis aculeata + Spongia.

On the Morphology of Arrowhead Flounders of the Genus Atheresthes in the Pacific Waters of the Northern Kuril Islands and Southeastern Kamchatka

This paper presents the results of studies on the morphology of arrowhead flounders, the Kamchatka flounder Atheresthes evermanni (35 specimens), and the American arrowtooth flounder A. stomias (37 specimens) collected in Pacific waters of the northern Kuril Islands and southeastern Kamchatka in 1998–1999. The morphology of the discussed species is compared with that of arrowtooth flounders from other areas. From this comparison, available information on the sharp increase in the density of the American arrowtooth flounder in the surveyed area (since 1997), and similarities in size compositions of the fish in Kuril and Aleutian waters, a conclusion has been made about the penetration of this species from Aleutian Pacific waters into the area of the northern Kuril Islands and southeastern Kamchatka. This is a result of expansion of the geographical range of this species due to general water warming in the northwestern Pacific during the second half of the 1990s.

Lycenchelys fedorovi: A New Species of Eelpout (Teleostei: Zoarcidae) from the Northwestern Pacific Ocean

Abstract Lycenchelys fedorovi is described from 42 specimens from the northern Kuril Islands, Russia. Unknown before 1993, specimens have been taken only along a rise complex in the western wall of the Kuril-Kamchatka Trench at depths of 190–700 m. The species differs from all congeners in the northwestern Pacific in lacking pelvic fins and is the fifth species of Lycenchelys to be described with this character state. The new species is most closely related to another northwestern Pacific congener, Lycenchelys maculatus, but differs from it in its lack of pelvic fins and predorsal scales, usually five postorbital pores, and whitish tail tip.