Some features of biology of butterfly sculpin Melletes papilio (Cottidae) in the pre-Kamchatka waters of the Sea of Okhotsk

Data on occurrence, spatial-bathymetric distribution, size-weight composition, size-sex structure, and food composition of butterfly sculpin Melletes papilio in the Sea of Okhotsk waters off the Kamchatka shores are given. This species is a relatively nonnumerous representative of fam. Cottidae with maximal length 42 cm and body weight to 960 g. In summer time, the species occurs practically over the whole study region at depths of 15 m to 285 m and water temperature near the bottom from ?0.9 to 10.7°C. However, the majority of individuals of this species occur within the depths range of 41–80 m in the cold intermediate water level at minimal positive (<2.0°C) and negative values of near-bottom water at sandy-silty grounds. The correlation between the harvesting depth and fish size has been analyzed. The variations of the feeding spectrum with growth of butterfly sculpin are described for the pre-Kamchatka waters of the Sea of Okhotsk.     

Biological features of the common fish species in Olyutorsky-Navarin region and the adjacent waters of the Bering Sea: 4. family sculpins (Cottidae)

Based on the materials of investigations conducted for 20 years (1995?2015), the features of biology of the common fish species of the family Cottidae from the northwestern Bering Sea are studied. These species are found during summer and fall in the waters of the Olyutorsky-Navarin region. The size–age parameters of the fishes collected with different fishing gears, as well as the features of their body length and body weight dynamics, spawning time, and spawning conditions, are described. The largest exemplars of shorthorn sculpin Myoxocephalus verrucosus and staghorn sculpins, armorhead sculpin Gymnocanthus galeatus and G. detrisus, are recorded in the catches of snurrevads, while the fishes caught in trawls are characterized by smaller size. Interannual variability of the size composition of the fish is related to the abundance of certain generations or to the fishery directed to different associations of sculpins. In the coastal waters, comparatively low average body size is usual for the majority of common sculpin species (with the exception of lords, yellow Irish lord H. jordani and Gilbert’s Irish lord H. gilberti) because of the dominance of juveniles.     

Feeding interactions and diet of carnivorous fishes in the Shelikhov Bay of the Sea of Okhotsk

The food spectra, trophic statuses, and feeding interrelations of three most abundant benthic carnivorous fish species inhabiting the Shelikhov Bay—the Pacific cod Gadus macrocephalus, the great sculpin Myoxocephalus polyacanthocephalus, and the Okhotsk sculpin M. ochotensis—are considered based on materials collected during the complex survey of the RV Professor Kaganovsky of the TINRO-Center, in September 2004. It was found that these species were facultative predators with wide food spectra. The significance of prey objects in the diet of the Okhotsk sculpin was as follows: crustaceans, fish, and mollusks. Great sculpin and Pacific cod preyed mostly on fish, then on crustaceans, and mollusks. Pacific cod ate equal proportions of fish and decapods. All the species had age-related variability of diet. The potential competition of great sculpin and Okhotsk sculpin for food was mitigated by the difference in the depths of their ranges, as well as by morphological (body size) and behavioral peculiarities in the areas where their habitats overlapped, and in microecosystems. The most probable competition was among Pacific cod 30–60 cm long and Okhotsk sculpin 20–50 cm in length, as well as among cod and great sculpins of all sizes.     

Feeding of Okhotsk sculpin Myoxocephalus ochotensis (Cottidae) in the Gulf of Shelikhov

Feeding of the Okhotsk sculpin Myoxocephalus ochotensis, an endemic of the northern part of the Sea of Okhotsk, is studied on the materials of two bottom trawl surveys in 2004–2005 in the Gulf of Shelikhov. The quantitative and qualitative characteristics of its food spectrum depending on the linear sizes are given. It is revealed that its food spectrum includes the crustaceans, mollusks, fishes, and polychaeta. In the composition of crustaceans being a basic food group, the gammarids and small species of shrimps are replaced by crabs and large shrimps as the fishes grow. It is found that the individuals of the Okhotsk sculpin with a length from 15 to 20 cm have a mixed type of feeding, and the fishes larger than 20 cm are predators to a greater extent.     

Specific features of distribution and size indices of four poorly studied species of sculpins (Cottidae) in the Okhotsk Sea Waters off Kamchatka

Evidence on occurrence in catches and characteristic of the spatial-bathymetric distribution and size indices of four species of Cottidae—frog sculpin Myoxocephalus stelleri, brightbelly sculpin Microcottus sellaris, antlered sculpin Enophrys diceraus, and furseal sculpin Stelgistrum stejnegeri—in summer-autumn months in the Okhotsk Sea waters off Kamchatka (site from 51°15′ to 57°20′ N, depths of 11–100 m) are provided. The first three species occur mainly in the northern part of the shelf above 54° N at depths smaller than 30–40 m within a comparatively well warmed surface water mass of seasonal modification at near-bottom temperature values above 6°C at various solid grounds. Maximum catches of S. stejnegeri were recorded only at a site of the western Kamchatka shelf from 54°00′ to 54°20′ N on pebbly-stony ground in a narrow bathy-metric range of 41–60 m on the boundary between the well warmed surface water mass of autumn modification and the cold intermediate water mass at a water temperature below 2°C. Evidence on the size-weight indices of the studied species of Cottidae in trawl catches in the Okhotsk Sea waters off Kamchatka in the study period is provided.     

Seasonal dynamics of growth and feeding of big-headed sculpin <Emphasis Type="Italic">Batrachocottus baicalensis</Emphasis> (Cottidae) in the Cape Berezovyi area (southern Baikal)

The seasonal features of the growth and feeding of one of the mass fish species of the littoral zone of Lake Baikal, big-headed sculpin Batrachocottus baicalensis, are investigated in the study area near the Cape Berezovyi (southern Baikal). It is found that the greatest increase of the linear parameters of the individuals of all age classes occurs in autumn, in the middle of the feeding period. Twenty-nine food objects, i.e., invertebrates and fishes, have been noted in the feeding spectrum of big-headed sculpin. It is found that the amphipods comprise the basic food year round. The transition of big-headed sculpin to predominant consumption of fish food is noted in the reproduction periods of other sculpins in the shallows. In general, the seasonal changing in species composition and food object ratio in the food are due to the fish life cycles, migrations of amphipods of different species, and, to a lesser extent, changing numbers of different groups of zoobenthos.     

Comparison of Ichthyofauna Composition in Different Areas of Russian and Korean Waters in Sea of Japan/East Sea

The specificity of the species composition of the ichthyofauna in the Russian and Korean waters in the Sea of Japan/East Sea (northwards from 35°17′N) is considered. The population and the proportion of species from the order of the perch-like fishes (Perciformes) steadily decline from the south towards the north; the proportion of the species from the order of the ray-finned fish (Scorpaeniformes) tends to rise. The northward latitudinal gradient in the family composition variability results in a decrease of their numbers along with a significant increase in the sculpins (Cottidae) and the picklebacks (Stichaeidae) in the species composition. In the southernmost region of the studied water area, the sublittoral species tend to prevail; in all of the others, the elittoral species are predominant. The four northern areas are characterized by a high similarity in the species composition (81.8%); this value is significantly lower (63.1%) in case of their comparison with the more southern areas. The similarity in the ichthyofauna composition between the southernmost area and the other studied water area comprises 44.1%.     

Comparative analysis of the karyotype of the sculpin Myoxocephalus ochotensis (Pisces: Cottidae) from the Odyan Bay of the Sea of Okhotsk

The karyotype of the endemic Okhotsk Sea sculpin Myoxocephalus ochotensis Schmidt (Cottidae) from Odyan Bay was studied. The number and morphology of chromosomes were determined, 2n = 42 (2 metacentric, 20 subtelocentric, and 20 acrocentric chromosomes), NF = 44. Variability of chromosome number was not revealed; no difference between male and female karyotypes was found. The karyotype of the Okhotsk sculpin M. ochotensis was compared with karyotypes of the Far East Steller’s M. stelleri (Tilesius), snow M. brandti (Steindachner), and plain M. jaok (Cuvier) sculpins, and to the European shorthorn sculpin M. scorpius (Linnaeus) from White Sea. Their similarities and distinctions were shown.     

Feeding ecology of dominant groundfish in the northern Bering Sea

We investigated current diets of the six most abundant benthic fish in the northern Bering Sea. Our objective was to explore feeding strategies and potential competition with other top predators as ecosystem changes occur in the northern Bering Sea ecosystem. Our approach used stomach content data collected from field sampling during spring 2006 and 2007. Calanoid copepods and ampeliscid amphipods were important prey of Arctic cod (Boreogadus saida) but in different proportions depending upon fish size, feeding location, and local environmental conditions. Snailfish (Liparidae) occupied a broad niche and fed on a variety of benthic amphipods. Arctic alligatorfish (Ulcina olrikii) and Arctic staghorn sculpin (Gymnocanthus tricuspis) consumed ampeliscid amphipods predominantly. Shorthorn sculpin (Myoxocephalus scorpius) had a less-diverse diet, with snow crab (Chionoecetes opilio) most important by weight. Finally, all Bering flounder (Hippoglossoides robustus) sampled had empty stomachs. Our results indicate that ampeliscid amphipods, which have high biomass in the central region of the northern Bering Sea, are the most important prey for the dominant groundfish in the Chirikov Basin. Generally, all dominant benthic fish in the northern Bering Sea had narrow feeding niches, except snailfish. High diet overlap was found among many of the fish species, including Arctic cod and snailfish, snailfish and Arctic alligatorfish, and Arctic alligatorfish and Arctic staghorn sculpin. These findings are consistent with a relatively short food chain for benthic fish that are for the most part specialized feeders with narrow preferences for food and may be affected by changes in benthic prey distributions.     

淞江鲈在中国地理分布的历史变迁及其原因

淞江鲈（Trachidermus fasciatus Heckel）隶属于鲉形目杜父鱼科淞江鲈鱼属,是中国四大淡水名鱼之一。该物种属暖温性底层小型肉食性降海洄游鱼类,曾在中国东南沿海地区较为常见,但近几十年来在许多地区却难以找到其踪迹。为查明其分布区的历史变化,1999年开始,通过查询文献资料和标本馆藏,结合实地考察,比较分析了有记载以来中国境内淞江鲈种群地理分布的历史变迁。结果显示,历史上,淞江鲈广泛分布于环太平洋的渤海、黄海、东海沿岸及与之相通的河流中。文献资料记载的分布区涵盖辽宁、河北、山东、江苏、浙江、福建、台湾7省和天津、上海2市;馆藏标本记录的仅涵盖辽宁、河北、山东、江苏、浙江5省和天津、上海2市;实地调查的现有种群分布区已退缩为辽宁、山东、浙江3省。造成淞江鲈种群分布区减小的原因主要在于人类干扰导致环境污染、洄游通道受阻、产卵场破坏等,致使其生存生境质量显著下降,甚至丧失,以至于其无法完成整个生命周期。基于目前的状况,建议进一步加强对该物种的拯救工作,进一步完善保护措施,使得该物种免遭灭绝之厄运。     

The karyotype of the great sculpin, <Emphasis Type="Italic">Myoxocephalus polyacanthocephalus</Emphasis> (Pallas, 1814) (Pisces: Cottidae), from the Russian part of the species range

The karyotype of the great sculpin, Myoxocephalus polyacanthocephalus (Pallas, 1814) (Pisces: Cottidae) from the Sea of Okhotsk and the Sea of Japan has been studied for the first time. The karyotype is stable; it consists of 40 chromosomes (4 metacentric, 2 submeta-subtelocentric, 20 subtelocentric, and 14 acrocentric chromosomes); the number of chromosomal arms is 44 + 2. Nucleolar organizer regions (NOR) are found in the telomeric region of the arm in one homologue of a pair of small metacentric chromosomes, using the Ag-NOR banding technique. A comparative analysis of the karyotype of M. polyacanthocephalus and the karyotypes of other Myoxocephalus species (M. stelleri, M. brandtii, M. jaok, M. ochotensis, and M. scorpius) has been carried out based on the main karyotype characters, as well as on the number and localization of NORs. The identified differences make it possible to differentiate the studied species, whereas the general traits indicate their taxonomic proximity.     

Activities of antioxidant enzymes and cytochrome c oxidase in liver of Arctic and temperate teleosts

Enhanced antioxidant status in polar fishes may occur due to high dissolved oxygen levels and membranes rich in peroxidation-sensitive polyunsaturated fatty acids. To evaluate the importance of antioxidant enzymes in polar fishes, activities of catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GR), as well as the aerobic enzyme cytochrome c oxidase (CCO), were measured at 6 degrees C and 1 degrees C in livers of confamilial Arctic and temperate teleosts: the Arctic fourhorn sculpin Triglopsis quadricornis (Cottidae) and saddled eelpout Lycodes mucosus (Zoarcidae) vs. the temperate longhorn sculpin (Myoxocephalus octodecimspinosus) (Cottidae) and ocean pout (Zoarces americanus) (Zoarcidae), respectively. At both assay temperatures, CAT activities were substantially lower in both Arctic species, SOD was similar in the cottids but lower in the Arctic zoarcid, and GR was similar in temperate and Arctic fishes. Activities at respective habitat temperatures were always significantly lower in the Arctic fishes. The lower antioxidant enzyme activities in the Arctic fishes cannot be attributed to lower aerobic status because CCO activity was similar or higher in the Arctic fishes; significant negative relationships were found between CCO and CAT and GR (but not SOD) when all species were combined, indicating that a higher apparent aerobic status does not necessarily coincide with higher antioxidant enzyme activities. Antioxidant enzyme activities may not be enhanced as part of cold adaptation in Arctic fishes, at least in the liver.     

Special traits of growth and feeding of the stone sculpin <Emphasis Type="Italic">Paracottus knerii</Emphasis> (Cottidae) in water bodies of different types

Growth and feeding of the stone sculpin Paracottus knerii (Cottidae) is investigated in Water Bodies of Different Types: Baikal (the littoral of its southern part), the Angara River, and the mountainous Sobolinoe Lake (the southern Baikal basin). The highest growth rate is characteristic of the South-Baikalian population, followed by the Angara population. The stone sculpin from Sobolinoe Lake is slow-growing. The growth rate of specimens of the latter is by 1.5–2 times lower than in the two aforementioned populations due to inferior feeding conditions of this water body. The size-age changes in the food spectrum of all investigated populations are consecutive change of all principal components and increase in size of the consumed prey     

Maximum Sizes of Some Species of Fish in the Far East State Marine Reserve, Peter the Great Bay, Sea of Japan

The results of 6-year-long observations on the size of some fish species of the Far East State Marine Reserve (Peter the Great Bay, Sea of Japan) suggest that resident fishes attain maximum size in the waters of the reserve. Compared to previously known sizes of fish, record values were found for the white-spotted greenling Hexagrammos stelleri (540 mm), the frog sculpin Myoxocephalus stelleri (490 mm), the snowy sculpin M. brandti (418 mm); the fringed blenny Chirolophis japonicus (520 mm), and some other fishes. These data confirm the opinion that the Marine Reserve waters are the reservation of the genofond of the inhabiting fish.     

The Karyotype of the Brightbelly Sculpin Microcottus sellaris (Gilbert, 1896) (Cottidae: Myoxocephalinae)

Russian Journal of Marine Biology - The karyotype of the brightbelly sculpin Microcottus sellaris (Gilbert, 1896) (family Cottidae) from the Sea of Japan and Sea of Okhotsk has been studied for the...     

黄海中部高眼鲽的摄食及随体长的变化

对2004年1月-2005年10月在黄海中部采集的622尾高眼鲽样品的胃含物进行分析.结果表明：高眼鲽摄食的食物种类包括11类38种,其中甲壳类和瓣鳃类为优势饵料类群,共占食物相对重要性指数百分比的99%;食物中的优势饵料种类为太平洋磷虾、脊腹褐虾和樱蛤.与20世纪80年代相比,黄海高眼鲽的摄食强度下降,食物组成发生了较大的变化;鱼类不再是优势饵料类群,鳀鱼在食物中所占的比例明显下降.通过聚类分析和列联表检验等方法对高眼鲽摄食随体长的变化进行研究,结果表明：体长在51～370 mm范围内的高眼鲽的摄食强度没有显著的体长变化,但不同体长组摄食的食物种类有一定差异.＜119 mm的主要以磷虾类和底层虾类为食;体长在120～199 mm的除以磷虾类和底层虾类为主要食物外,还摄食相当比例的瓣鳃类和鱼类;＞200 mm的则主要摄食底层虾类和鱼类,磷虾类所占比例减小.     

Diet composition,feeding niche partitioning and trophic organisation of large pelagic predatory fishes in the eastern Arabian Sea

Information on the ecology and feeding behaviour of the large oceanic predatory fishes is crucial for the ecosystem approaches to fisheries management models. Co-existing large pelagic predators in the open oceans may avoid competition for the limited forage by resource partitioning on spatial, temporal or trophic levels. To test this, we studied the prey species composition, diet overlap, trophic level, and trophic organisation of 12 large predatory fishes co-existing in the eastern Arabian Sea. Stomach contents of 1,518 specimens caught by exploratory longline operations in the Indian Exclusive Economic Zone during the years 2006–2009 were analysed. Finfishes were dominant prey of all species except blue marlin (Makaira nigricans) and yellowfin tuna (Thunnus albacares), which fed mainly on cephalopods, and long-snouted lancetfish (Alepisaurus ferox) and pelagic stingray (Pteroplatytrygon violacea), which fed mainly on crustaceans. Common dolphinfish (Coryphaena hippurus) and yellowfin tuna fed on a wider variety of prey than the other species, while the diets of lancetfish and black marlin (Istiompax indica) were narrowest. Pelagic stingray and great barracuda (Sphyraena barracuda) fed on species occupying epipelagic waters, whereas the contribution of mesopelagic prey was higher in the diets of swordfish (Xiphias gladius) and pelagic thresher (Alopias pelagicus). Trophic levels of these fishes ranged from 4.13 to 4.37. Diet overlap index revealed that some of the large pelagic predatory fishes share common prey species. Cluster analysis of the diets revealed four distinct trophic guilds namely ‘flyingfish feeders’ (common dolphinfish and great barracuda); ‘mesopelagic predators’ (pelagic thresher and swordfish); ‘crab feeders’ (lancetfish, pelagic stingray and silky shark) and ‘squid feeders’ (yellowfin tuna, Indo-Pacific sailfish (Istiophorus platypterus), skipjack tuna (Katsuwonus pelamis), black marlin and blue marlin). Large predatory fishes of the eastern Arabian Sea target different prey types, and limit their vertical extent and time of feeding to avoid competing for prey.     

Ecological and zoogeographic characterization of the ichthyofauna of Sivuch’ya Bay (Peter the Great Bay,Sea of Japan)

An inventory of the ichthyofauna of Sivuch’ya Bay (Far Eastern State Marine Biosphere Reserve) was made for the first time. Based on the results of our research (during all seasons of 1994–2004), the list of Sivuchya Bay fishes includes 108 species belonging to 15 orders, 45 families, and 84 genera. The greatest number of taxa was found for the orders Perciformes (17 families, 33 genera, and 40 species) and Scorpaeniformes (8, 18, and 28, respectively). The following families dominate in terms of the number of species: Stichaeidae, 15 species; Cottidae, 11; Pleuronectidae, 9; Gobiidae, 5; Hexagrammidae, 5; Clupeidae, 4; and Tetraodontidae, 4. These seven families include 53 species (49.1%). The data, confirmed by the results of regression analysis, show that the bay ichthyofauna is well studied. Zoogeographical analysis indicates that the bulk of ichthyofauna is constituted by fishes of Asian origin (low boreal, low boreal-subtropical and widely distributed boreal), 80 species (74.1%). Bottom and near-bottom fishes are dominating elements of the Sivuch’ya Bay ichthyofauna, with 83 species (76.9%); pelagic fishes 25 species make up (23.1%).     

The karyotype of the flathead sculpin Megalocottus platycephalus platycephalus (Pallas, 1814) (Pisces: Cottidae) from Odyan Bay,Sea of Okhotsk

This study deals with the karyotype of the flathead sculpin Megalocottus platycephalus platycephalus (Pallas, 1814) (family Cottidae) from Odyan Bay of the Sea of Okhotsk. The karyotype is stable: 2n = 42 (2 metacentric, 2 submeta-subtelocentric, 30 subtelocentric, and 8 acrocentric chromosomes), NF = 44 + 2. The nucleolar organizers (NOs) were identified using Ag-banding in the telomere parts of the short arms of two large subtelocentric chromosomes. Variations in the number of nucleolar organizer chromosomes and in the number of NO-staining blocks were found. Comparison of the karyotype of M. p. platycephalus with the karyotypes of previously studied species of the genus Myoxocephalus from the Sea of Japan and the Sea of Okhotsk revealed their significant similarity in the main features and difference in the number and localization of NORs.