Sakhalin sturgeon Acipenser mikadoi (Acipenseridae): results of study and proposed measures for conservation of the species

All available data on sakhalin sturgeon Acipenser mikadoi are summarized. Its historical and modern habitats are described and their significant reduction is noted. Now the species is abundant in the Russian part of its range only — in the Tumnin River, where it is represented in commercial catches by two clearly different groups: large-sized juveniles (FL 43–68 cm) and mature fish (FL 135–169 cm). Juveniles of sakhalin sturgeon migrate during their first years, as their osmoregulatory system forms, to the lower reaches of Tumnin, to the internal estuary, and then to the Datta Bay, the Tatar Strait and the Japan Sea. When returned to the Tumnin, the spawners of sakhalin sturgeon have the length 135–169 cm (n = 29) and weight 15–36 kg. Sex ratio among the caught mature fish is 13.0 : 4 or 3.2 : 1 for females : males, on average. Fecundity of the sturgeon females sampled for artificial reproduction varied from 44.8 to 150.0 thousand eggs, on average 87.3 ± 12.1 . 103 eggs. In total, 17 mature spawners of A.mikadoi were caught in the Tumnin River in 2006–2019 for artificial reproduction (♀ = 13, ♂ = 4), 13 individuals were injected, among them 4/5 of females and 2/3 of males gave high-quality sex products. Producers of this species were distinguished by high survival during manipulations of fish breeding (100 %). Their progeny had low survival, both embryos during incubation and juveniles during rearing; the survival rate for the stage from eggs laid for incubation to juveniles with weight 3.4–7.0 g was 1.85 %. The low survival was supposedly reasoned by combination of unfavorable environmental factors and fish-breeding manipulations. Totally 11,214 juveniles of sakhalin sturgeon with weight from 3.4 to 7.0 g were released into the natural habitat (Tumnin river) in 2007, 2008, 2015, 2017, and 2019. At Anyui sturgeon fish hatchery, the broodstock of sakhalin sturgeon with 274 individuals of 5 ages is created and operated successfully. The male sturgeons in the hatchery mature at the age of 8 years. Here, 11 males of the 2007–2008 year-classes participated in the spawning in 2015–2019. Re-maturation of males was not recorded yet. For the broodstock formation in other fish hatcheries, 200 juveniles of sakhalin sturgeon were transferred to them. To preserve the species, a set of measures is proposed to strengthen its protection and to enhance its artificial reproduction, including the fry releasing into the rivers of the mainland coast, Sakhalin Island, and Japan.

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Current Data on Sakhalin Sturgeon Acipenser mikadoi (Acipenseridae, Acipenseriformes) Biology (Review)

Inland Water Biology ◽

10.1134/s1995082921060080 ◽

2021 ◽

Vol 14 (6) ◽

pp. 722-731

Author(s):

E. V. Mikodina ◽

G. I. Ruban

Keyword(s):

Current Data ◽

Sakhalin Sturgeon ◽

Acipenser Mikadoi

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Innovative Biotechnology of Artificial Reproduction of Fish Populations

Vestnik APK Verhnevolzh`ia ◽

10.35694/yarcx.2020.51.3.003 ◽

2020 ◽

Author(s):

П.Е. Гарлов

Keyword(s):

Pituitary Gland ◽

Sea Water ◽

Natural Populations ◽

Ecological Factors ◽

Water Supply Systems ◽

Artificial Reproduction ◽

Fish Farms ◽

Commercial Fish ◽

Fish Breeding ◽

Critical Salinity

С целью повышения эффективности искусственного воспроизводства популяций ценных видов рыб разработаны новые методы управления их размножением, выживаемостью и ростом, которые представлены в виде изобретений. Для управления размножением производителей разработаны методы стимуляции и задержки полового созревания производителей осетровых и костистых рыб. Для стимуляции полового созревания были разработаны препараты изолированной передней и изолированной задней долей гипофиза. Их внедрение в осетроводстве позволило повысить степень их рыбоводного использования в среднем на 15% и достичь экономии гипофиза до 40%. Для задержки полового созревания производителей разработан метод их промышленного резервирования в среде критической солёности 4–8‰, причём как в морской воде, так и в растворах поваренной соли. Производственными испытаниями доказана возможность сохранения рыбоводного качества производителей и получения доброкачественного потомства в этой среде при верхних нерестовых температурах в течение производственно необходимых сроков. С целью заводского воспроизводства природных популяций промысловых рыб разработан метод управления их размножением триадой адекватных экологических факторов ‒ «критической» солёностью, температурой и освещённостью при видоспецифических пороговых воздействиях. На этой основе разработан полносистемный метод воспроизводства популяций ценных видов промысловых рыб (севрюги и Балтийского лосося), охватывающий все этапы заводской биотехники. Новый метод осуществляется путём массовой морской заготовки производителей, получения потомства в морских садках и, после заводского речного выращивания молоди до готовности к миграции, конечного доращивания в морских садках крупной жизнестойкой молоди. Для промышленного внедрения всей предложенной биотехники и круглогодичной аквакультуры разработаны системы водоснабжения рыбоводных заводов и рыбоводных хозяйств на основе внесезонного подземного гидрокондиционирования среды выращивания и на природно-промышленных принципах инженерной экологии. In order to increase the efficiency of artificial reproduction of populations of valuable fish species new methods for managing their reproduction, survival and growth have been developed, which are presented in the form of inventions. To control the reproduction of producers methods have been developed to stimulate and delay puberty of sturgeon and bony fish producers. To stimulate puberty preparations for the isolated anterior and isolated posterior lobes of the pituitary gland have been developed. Their introduction in sturgeon breeding made it possible to increase the degree of their fish farming use by an average of 15% and to achieve a pituitary gland economy of up to 40%. To delay the puberty of producers, a method for their industrial reservation in an environment of critical salinity of 4–8‰ has been developed both in sea water and in solutions of sodium chloride. Production tests have proven the possibility of preserving the fish-breeding quality of producers and obtaining benign offspring in this environment at the upper spawning temperatures during the production required periods of time. With the aim of factory reproduction of natural populations of commercial fish a method has been developed to control their reproduction by a triad of adequate ecological factors – “critical” salinity, temperature and illumination under species-specific threshold effects. On this basis a full-system method of reproducing populations of valuable species of commercial fish (stellate sturgeon and Baltic salmon) has been developed covering all stages of factory biotechnology. The new method is carried out by mass marine harvesting of producers obtaining offspring in sea pens and after the factory river rearing of hatchling until ready for migration the final rearing of large viable juveniles in sea pens. For the industrial introduction of all the proposed biotechnics and year-round aquaculture, water supply systems for fish breeding plants and fish farms were developed on the basis of off-season underground hydroconditioning of the growing environment and on the natural and industrial principles of engineering ecology.

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Seasonal changes of biological condition and reproductive cycle of hampback shrimp Pandalus hypsinotus (Caridea, Pandalidae) in the Tatar Strait

Izvestiya TINRO ◽

10.26428/1606-9919-2021-201-547-560 ◽

2021 ◽

Vol 201 (3) ◽

pp. 547-560

Author(s):

D. N. Yuriev ◽

G. V. Zhukovskaya

Keyword(s):

Reproductive Cycle ◽

Japan Sea ◽

Biological Condition ◽

Tatar Strait ◽

Stage Of Development ◽

Long Time ◽

Pass Through ◽

The Individual ◽

Almost All ◽

Trawl Catches

Research and commercial trawl catches of humpback shrimp Pandalus hypsinotus from the Tatar Strait (Japan Sea) in 2004–2020 were investigated, with bioanalysis of about 45 thousand specimens. Average timing of group molting, spawning, and eggs laying are determined, terms of gonads and eggs development are estimated. Prespawning and molting of the females occur between January-April, with the peaks in early February and middle February, respectively. All oviparous females have 30–40 days to lay eggs, and molt during 50–55 days; the peak of the eggs laying occurs in late June. The males molt in July-August, afterwards the largest individuals change gender and new intersexes are formed. The males have the second molting in October-December, with the peak in late November. In January, after finish of the males molting, a new annual reproduction cycle starts from the prespawning molting of females. Both vitellogenesis and embryogenesis are observed through the year, though females with developing gonads prevail from August to January (because of a long time span between winter and summer moltings while the egg carrying continued 15 months) but oviparous females — from February to July. The individual reproductive cycle of Pandalus hypsinotus in the Tatar Strait lasts 24 months, with 9 months of vitellogenesis (quick growth of gonads) and 15 months of embryogenesis. During the 2-year reproductive cycle, most of females pass through the following stages: i) gonads development (just after eggs laying) when almost all oviparous females (up to 95 % in May) have green gonads under carapace that corresponds to the stage of development «eggs laid — gonads weakly developed»; ii) summer molting from August when females lose hairs on pleopods and the gonads growth accelerates; iii) respawning in January-March (together with the firstly spawning intersexes, with slight delay of the latter); iv) initial developing of eggs during summer; v) stage of «eyed eggs» from December to March; and vi) eggs laying and molting from late March to late May; then the 2-year reproductive cycle repeats.

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Structure of ripe oocytes of the Sakhalin sturgeon Acipenser mikadoi

Doklady Biological Sciences ◽

10.1134/s0012496611050176 ◽

2011 ◽

Vol 440 (1) ◽

pp. 320-323

Author(s):

E. V. Mikodina ◽

A. V. Novosadova

Keyword(s):

Sakhalin Sturgeon ◽

Acipenser Mikadoi

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The validation of specific status of the sakhalin sturgeon Acipenser mikadoi (Acipenseridae) in the light of recent genetic and morphological data

Journal of Ichthyology ◽

10.1134/s003294520910004x ◽

2009 ◽

Vol 49 (10) ◽

pp. 868-873 ◽

Cited By ~ 6

Author(s):

E. D. Vasil’eva ◽

V. P. Vasil’ev ◽

S. V. Shedko ◽

G. V. Novomodny

Keyword(s):

Morphological Data ◽

Sakhalin Sturgeon ◽

Acipenser Mikadoi

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THE BUBBLE SEEPAGE AREAS IN THE TATAR STRAIT OF THE JAPAN SEA

10.35976/poi.2020.51.43.011 ◽

2020 ◽

Author(s):

А.С. Саломатин

Keyword(s):

Japan Sea ◽

Tatar Strait ◽

The Japan Sea ◽

Characteristic Features

На основе данных гидроакустических исследований шести морских экспедиций построены карты-схемы положения зон пузырьковой разгрузки метана в Татарском проливе Японского моря у о. Сахалин. Выявлены характерные особенности распределения зон пузырьковой разгрузки метана по глубине, их связи с особенностями морского дна. Оценены размеры этих зон на морском дне. The maps of bubble seepage areas in the Tatar Strait of the Japan Sea based on the data of hydroacoustic studies six marine expeditions were constructed. Characteristic features of distribution of bubble seepage areas on depth and their connection with features of the seabed were revealed. The sizes of these seepage areas on the seabed were estimated.

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Gonodal development of the peacock bass Cichla monoculus (Perciformes: Cichlidae) in the Middle Solimões

Scientific Magazine UAKARI ◽

10.31420/uakari.v7i1.98 ◽

2011 ◽

Vol 7 (1) ◽

pp. 41-55 ◽

Cited By ~ 3

Author(s):

Rosângela Lira de Souza ◽

Daíza Lima da Silva ◽

Ana Carolina Prado Valladares ◽

Rossineide Martins da Rocha ◽

Maria Auxiliadora Pantoja Ferreira ◽

...

Keyword(s):

Amazon Basin ◽

Condition Factor ◽

Natural Habitat ◽

Gonadal Development ◽

Commercial Fishing ◽

Natural Environments ◽

Tissue Slices ◽

Average Fecundity ◽

Peacock Bass

The common peacock bass, Cichla monoculus Spix; Agassiz, 1831, is a Neotropical cichlid native to the Amazon basin. Although it is highly valued for the quality of its flesh and intensely exploited by commercial fishing, representing the fourth most sold fish along the middle Solimões River in terms of landing statistics, little is known of the reproductive characteristics of this species in its natural habitat. The objective of this work was to reveal some morphological and histological aspects of gonadal development for this species. We also wanted to verify the gonadosomatic relation and allometric condition factor, and assess their use as reproductive indicators. Finally, we intended to reveal the fecundity and spawning type for some individuals of this species living in natural environments. In this study 73 females and 72 males of C. monoculus were utilized, from whom data were collected on total weight and total individual length. The gonads were later removed, weighed and macroscopically analyzed. To confirm this analysis tissue slices were taken from tissue cuts from 41 of the gonads. Based on the results of macroscopic and histological analyses five stages of development for females and four for males were identified. The ovaries were classified as immature, maturing, mature, spawned and at rest. The testicles were classified as immature, maturing, mature and spermiated. The females were found to be larger than the males, but the males were heavier. The gonadosomatic relation and the allometric condition factor were not considered good indicators of the reproductive status for this species. The spawning observed was of the total type, presenting an absolute average fecundity of 8,624 mature oocytes. Diameters of the vitellogenic oocytes varied from 1,210 μm to 3,000 μm. The total spawn, which is accompanied by oocytes with large diameters that have a large reserve of vitellus, is a factor that may favor the reproductive success of C. monoculus on the middle Solimões.

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