Spawning Activities of the Fluvial Japanese Charr Salvelinus leucomaenis and Incubation of Their Eggs at the Artificial Spawning Sites.

Abstract Balanced harvest (BH) proposes to distribute a moderate mortality from fishing across the widest possible range of species, stocks, and sizes in an ecosystem, in proportion to their natural productivity so that the relative size and species composition are maintained, in line with the CBD requirement for sustainable use. This proposal has many and not always intuitive implications for fisheries management, e.g. in relation to selectivity, protection of juveniles and spawning sites, models of harvesting strategies, a focus on size and species, the impacts of discarding, aspects of emblematic species and ecosystem services, operational complexity, partial implementation, ecosystem rebuilding, and relations with broader management frameworks. The paper closes with a discussion of BH implementation, concluding that a logical step would be to integrate several separate initiatives to move fisheries into a more ecosystem-conscious context. Implementation challenges will be encountered, but there are lessons to be drawn from fishery ecosystems already close to BH, as in some tropical multispecies fisheries, and further, the implementation challenges are already being taken on in many well-managed fisheries and areas as management begins to address the realities of what ecosystem-based fishery management actually entails.

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Is it possible to predict habitat use by spawning salmonids? A test using California golden trout (Oncorhynchus mykiss aguabonita)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-081 ◽

1999 ◽

Vol 56 (9) ◽

pp. 1576-1584 ◽

Cited By ~ 28

Author(s):

Roland A Knapp ◽

Haiganoush K Preisler

Keyword(s):

Oncorhynchus Mykiss ◽

Water Depth ◽

Parametric Model ◽

Water Velocity ◽

Habitat Characteristics ◽

Nonparametric Model ◽

Habitat Features ◽

Substrate Size ◽

Depth Water ◽

Spawning Sites

It is widely believed that stream salmonids select spawning sites based on water depth, water velocity, and substrate size. Attempts to predict spawning locations using these habitat features have met with little success, however. In this study, we used nonparametric logistic regression to determine what habitat features were associated with the locations chosen by spawning California golden trout (Oncorhynchus mykiss aguabonita). From this nonparametric model, we developed a parametric model that incorporated the habitat features most strongly associated with spawning sites and used this model to calculate the probability of use by spawning golden trout for specific stream locations. The overall nonparametric model was highly significant and explained 62% of the variation in spawning location. Four of the eight habitat variables, substrate size, water depth, water velocity, and stream width, had highly significant effects and alone explained 59% of the variation in spawning location. The results of a cross-validation procedure indicated that the parametric model generally provided a good fit to the data. These results indicate that location-specific probabilities of use were predictable based on easily measured habitat characteristics and that nonparametric regression, an approach still rarely used in ecological studies, may have considerable utility in the development of fish-habitat models. Given the escalating pace at which fish habitats are being altered, such models are increasingly important in predicting the effects of these alterations on populations.

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Microsatellite variation in white-spotted char Salvelinus leucomaenis from Sakhalin oblast

Russian Journal of Genetics ◽

10.1134/s1022795413090020 ◽

2013 ◽

Vol 49 (9) ◽

pp. 945-949 ◽

Cited By ~ 3

Author(s):

K. I. Afanas’ev ◽

G. A. Rubtsova ◽

E. G. Shaikhaev ◽

L. A. Zhivotovskii

Keyword(s):

Microsatellite Variation ◽

Salvelinus Leucomaenis ◽

White Spotted Char ◽

Sakhalin Oblast

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Variation in Population Structures of Tropical Freshwater Eels, Anguilla Marmorata, A. Bicolor Bicolor and A. Bengalensis Bengalensis, in the Indo-Pacific

10.21203/rs.3.rs-136957/v1 ◽

2021 ◽

Author(s):

Takaomi Arai ◽

Hussein Taha

Keyword(s):

Tropical Species ◽

Pacific Region ◽

Oceanic Current ◽

Dispersion Patterns ◽

Population Structures ◽

Different Populations ◽

And Migration ◽

Current Systems ◽

Freshwater Eels ◽

Spawning Sites

Abstract Freshwater eels, genus Anguilla, have a distinctive catadromous life history, which could be associated with certain oceanic current systems and offshore spawning sites. Thus, migration and dispersion patterns are believed to be important factors influencing the population structures of each species. Temperate eel species are well studied, while little research has been conducted on the tropical counterparts that comprise two-thirds of all eel species. The population structures of three tropical species, A. marmorata, A. bicolor bicolor and A. bengalensis bengalensis, which are distributed widely in the Indo-Pacific region, were explored by means of DNA sequence analysis of mitochondrial cytochrome c oxidase subunit I (COI). This study found that A. bicolor bicolor had two genetically distinct populations, and these different populations co-occur geographically in the Indo-Pacific region, while A. marmorata and A. bengalensis bengalensis showed a panmictic-population structure in this region. The populations of A. bicolor bicolor were also found to have lower genetic variability than the populations of A. marmorata and A. bengalensis bengalensis. This study is the first to explore the population genetic structure of A. bengalensis bengalensis. The present results also suggest plausible dispersion and migration of these tropical species into their continental habitats.

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Inventaire spécifique et caractéristiques de quelques frayères du lac de Buyo dans le Parc National de Taï (Sud-Ouest Côte d’Ivoire)

Journal of Applied Biosciences ◽

10.35759/jabs.145.6 ◽

2020 ◽

Vol 145 ◽

pp. 14902-14913

Author(s):

N’DRI Olga Rosemonde ◽

KONAN Yao Aristide ◽

MONNEY Attoubé Ida ◽

KONE Tidiani

Keyword(s):

Cote D'ivoire ◽

National Park ◽

Sexual Maturity ◽

Côte D’Ivoire ◽

Cote D’Ivoire ◽

Taï National Park ◽

Côte D'ivoire ◽

Spawning Areas ◽

Tai National Park ◽

Spawning Sites

Objectifs : Des investigations ont été menées dans 11 sites du lac de Buyo situés sur le cours du fleuve Sassandra dans le Parc National de Taï (Côte d’Ivoire) en vue de connaître les espèces de poisson qui utilisent ces zones comme sites de reproduction. Méthodologie et Résultats : Dans chaque site d’échantillonnage, les variables environnementales ont été mesurées et les poissons ont été capturés à l’aide de filets maillants. Les stades de maturité sexuelle avancés ont été considérés comme critères de reconnaissance des sites de fraie. La richesse spécifique a été de 32 espèces, répartie en 13 familles et dominée par les Cichlidae (7 espèces, soit 22%). Sur la base des stades sexuels de maturité, 14 espèces, en phase de reproduction, ont été capturées dans les 11 sites d’échantillonnage. Les résultats de l’analyse des sédiments ont indiqué une prédominance de sable (>60%) dans les sites de reproduction et des valeurs optimales de température (28,52°C), de pH (6,53), de conductivité (36,50 μS/cm) et d’oxygène dissous (5,37 mg/l). Conclusion et application des résultats : La présente étude a montré que les sites échantillonnés dans le lac de Buyo situé à l’intérieur du le Parc National de Taï sont caractérisés par des sédiments sableux et constituent des frayères pour plusieurs espèces de poisson. La localisation de ces zones de reproduction représente donc un outil important pour les gestionnaires dans la conservation de la diversité piscicole du parc national de Taï. Mots clés : sites de frai, stade de maturité sexuelle, ichtyofaune, lac de barrage de Buyo. Specific inventory and characteristics of some spawning grounds of Lake Buyo in the Taï National Park (South-West Côte d'Ivoire) Abstract Objectives: Investigations were carried out in 11 sites of Lake Buyo located in the midstream of Sassandra River in Taï National Park (Côte d'Ivoire) to get to know fish species that use these areas as spawning sites. Methodology and Results: Environmental variables were measured in each sampling sites and fish were caught using gillnets. Advanced stages of sexual maturity were considered as recognition criteria of spawning areas. Specific richness was of 32 species, belonging in 13 families and dominated by Cichlidae (7 species, 22%). Based on advanced sexual maturity stages, 14 species in spawning period, were captured at the 11 sampling sites. Results of sediment analysis indicated a predominance of sand (> 60%) in spawning sites and optimal values of temperature (28.52°C), pH (6,53), conductivity (36,50 μS/cm) and dissolved oxygen (5,37 mg/l). Conclusion and application of results: The present study showed that sites sampled in Lake Buyo located within the Tai National Park are characterized by sandy sediments and constitute spawning areas for several fish species. The location of these spawning areas therefore is an important tool for managers in conserving fish diversity of Taï National Park. Keywords: spawning sites, stage of sexual maturity, Ichtyofauna, Buyo Dam Lake.

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Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters

Aquatic Biology ◽

10.3354/ab00529 ◽

2013 ◽

Vol 19 (3) ◽

pp. 201-206 ◽

Cited By ~ 9

Author(s):

M Skovrind ◽

EAF Christensen ◽

H Carl ◽

L Jacobsen ◽

PR Møller

Keyword(s):

Perca Fluviatilis ◽

Perch Perca Fluviatilis ◽

Spawning Sites

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Swimming depth of migrating silver eels Anguilla japonica released at seamounts of the West Mariana Ridge, their estimated spawning sites

Marine Ecology Progress Series ◽

10.3354/meps186265 ◽

1999 ◽

Vol 186 ◽

pp. 265-269 ◽

Cited By ~ 20

Author(s):

J Aoyama ◽

K Hissmann ◽

T Yoshinaga ◽

S Sasai ◽

T Uto ◽

...

Keyword(s):

Anguilla Japonica ◽

The West ◽

Swimming Depth ◽

Silver Eels ◽

Spawning Sites

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An Electrophysiological Basis for Olfactory Discrimination in Homing Salmon: A Review

Journal of the Fisheries Research Board of Canada ◽

10.1139/f70-059 ◽

1970 ◽

Vol 27 (3) ◽

pp. 565-586 ◽

Cited By ~ 32

Author(s):

Toshiaki J. Hara

Keyword(s):

Pacific Salmon ◽

Electrical Response ◽

High Amplitude ◽

Polluted Water ◽

Sensitive Period ◽

Young Fish ◽

Spawning Site ◽

Short Period ◽

Sign Stimulus ◽

Spawning Sites

Past and current researches relating to olfactory acuity and discrimination in fishes, with special reference to homing salmon, are reviewed.When the nasal sac of spawning Pacific salmon is stimulated with water from the spawning site a high amplitude electroencephalographic response of characteristic pattern is recorded from the olfactory bulb. This electrical response is specific in the sense that it cannot be evoked by water from spawning sites of other groups of breeding salmon. Further, the salmon respond clearly to water taken from places along their migratory routes below the spawning sites. These findings suggest that olfaction is an important factor in guidance during the final phases of homeward migration of salmon. It is also possible that salmon retrace sequentially a trail of stimuli that is the reverse of that imprinted in the young fish on their seaward migration.Although the available data do not delineate the sensitive period, or the duration of the imprinting process, there is accumulating evidence that only a short period is necessary for imprinting, which may occur when the smolts are in their freshwater life.Recent study on the effect of antimetabolites (puromycin, actinomycin D, or cycloheximide) on olfactory bulbar discrimination in homing salmon suggests that long-term olfactory memory in these fish depends upon continued metabolism of RNA and continued protein synthesis. The possibility that the imprinting process in young fish may be affected by polluted water, which has recently become a serious problem in fisheries, is discussed. The need for electrophysiological as well as biochemical studies at a macromolecular level of the imprinting process is emphasized.Finally, the hypothesis is discussed that a home stream odour may act most effectively as a simple "sign stimulus," which, through the release of a positive rheotropic response, induces the fish to move upstream toward home. This is largely based on the recent experimental observations of the orientation mechanism in several species of teleost fishes.

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Modeling framework to estimate spawning and hatching locations of pelagically spawned eggs

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2018-0047 ◽

2019 ◽

Vol 76 (4) ◽

pp. 597-607 ◽

Cited By ~ 9

Author(s):

Holly S. Embke ◽

Patrick M. Kocovsky ◽

Tatiana Garcia ◽

Christine M. Mayer ◽

Song S. Qian

Keyword(s):

Great Lakes ◽

Field Data ◽

Ctenopharyngodon Idella ◽

Native Range ◽

Invasive Fish ◽

Modeling Framework ◽

Hydraulic Models ◽

Successful Recruitment ◽

Grass Carp Ctenopharyngodon Idella ◽

Spawning Sites

Identifying spawning and hatching locations is vital to controlling invasive fish and conserving imperiled fish, which can be difficult for pelagically spawning species with semi-buoyant eggs. In freshwater systems, this reproductive strategy is common among cyprinid species, such as Chinese carp species currently threatening the Great Lakes. Following the confirmation that one of these species, grass carp (Ctenopharyngodon idella), was spawning in a Great Lakes tributary, we developed a modeling framework to combine field data with hydraulic models to calculate the most probable spawning and hatching locations for collected eggs. Our results indicate that the estimated spawning location encompassed habitat consistent with spawning sites in grass carp’s native range. Additionally, all eggs were identified to have hatched in the river, increasing the likelihood of successful recruitment. This modeling framework can be used to estimate spawning and hatching locations for Chinese carp species, as well as all pelagic, riverine spawners. Spawning and hatching locations provide key information to researchers about the reproductive requirements of species and to agencies about how best to manage populations for control or restoration.

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