Effects of muscle lipid concentration on wild and hatchery brown trout (Salmo trutta) smolt migration

2012 ◽  
Vol 69 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Stefan Larsson ◽  
Ignacio Serrano ◽  
Lars-Ove Eriksson
Keyword(s):  
Baltic Sea ◽  
Salmo Trutta ◽  
Lipid Concentration ◽  
The Baltic Sea ◽  
Muscle Lipid ◽  
Brown Trout Salmo Trutta ◽  
Migratory Pattern ◽  
Wild Trout ◽  
The Baltic ◽  
Sea Survival

Annually, hatchery programs are releasing millions of salmonid smolts into the Baltic Sea. Recent estimations indicate a decline in smolt sea survival, questioning the ecological and socioeconomic values of these programs. Concurrently, hatchery smolts have increased in lipid concentration. Salmonids display partial migration, and it is suggested that the ratio of migrants/residents is affected by individual smolt energetic status. To test whether the increased energetic status of hatchery smolts could explain the noted decrease in survival, we released wild trout smolts, conventional hatchery smolts, and hatchery smolts of low energetic status into a Baltic Sea river. Using telemetry, we obtained data on the number of successful migrants, their swimming speed, and diel migratory behaviour. A much lower proportion of conventional smolts (30%) successfully migrated to the coast. No difference was found between wild (74%) and hatchery smolts of low energetic status (64%). Furthermore, conventional smolts migrated slower and showed no diel migratory pattern. The results are of high relevance for hatchery programs producing partially migrating fish.

Cormorant impact on trout (Salmo trutta) and salmon (Salmo salar) migrating from the river Dalälven emerging in the Baltic Sea

2009 ◽  
Vol 98 (1-3) ◽  
pp. 16-21 ◽  
Author(s):  
Maria Kristina Boström ◽  
Sven-Gunnar Lunneryd ◽  
Lars Karlsson ◽  
Bjarne Ragnarsson
Keyword(s):  
Baltic Sea ◽  
Salmo Salar ◽  
Salmo Trutta ◽  
The Baltic Sea ◽  
The Baltic

Effects of marine conditions, fishing, and smolt traits on the survival of tagged, hatchery-reared sea trout (Salmo trutta trutta) in the Baltic Sea

2007 ◽  
Vol 64 (9) ◽  
pp. 1183-1198 ◽  
Author(s):  
Irma Kallio-Nyberg ◽  
Irma Saloniemi ◽  
Eero Jutila ◽  
Ari Saura
Keyword(s):  
Survival Rate ◽  
Baltic Sea ◽  
Salmo Trutta ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Survival Rates ◽  
Clupea Harengus ◽  
The Baltic Sea ◽  
Sea Trout ◽  
The Baltic

The marine survival of tagged sea trout (Salmo trutta trutta) smolt groups (n  =  236) stocked from 1970 to 2001 in the Baltic Sea was analysed using a linear mixed model. The response variable, survival rate, was associated with smolt size, release date, sea surface temperature in May, and prey fish abundance, and interactions among these factors. The effect of smolt size was in interaction with Baltic herring (Clupea harengus membras) abundance; smolt size had an optimum of about 22 cm in years when herring were abundant, but when herring were less abundant, the survival of larger smolts was higher. Early stocking in warm springs or late stocking in cold springs gave the best survival rates for trout. Changes in return activity or fishing methods have made tag returns a less reliable way of estimating survival during the last 30 years. The actual return rate of undersized fish (<40 cm) compared with their estimated proportion among captured fish decreased over time, which suggests that the survival rate for the later years was probably underestimated. It is likely that we were unable to include all the relevant explanatory variables in the model, as year effects remained significant, suggesting unknown annual variation affecting survival.

Temporal and spatial sedimentation rate variabilities in the eastern Gotland Basin, the Baltic Sea

Boreas ◽  
2002 ◽  
Vol 31 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Christian Christiansen ◽  
Helmar Kunzendorf ◽  
Kay-Christian Emeis ◽  
Rudolf Endler ◽  
Ulrich Struck ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Sedimentation Rate ◽  
The Baltic Sea ◽  
Gotland Basin ◽  
Temporal And Spatial ◽  
The Baltic

Russian Oil: Production and Exports

2003 ◽  
pp. 136-146
Author(s):  
K. Liuhto
Keyword(s):  
Baltic Sea ◽  
Statistical Data ◽  
Oil Production ◽  
The Baltic Sea ◽  
North West ◽  
The North ◽  
Oil Transportation ◽  
Sea Ports ◽  
The Baltic

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.

Paleoecological study of bottom sediments of the lake Goluboye (Karelian Isthmus) according to the results of diatom analysis

2019 ◽  
pp. 265-269
Author(s):  
Angelina E. Shatalova ◽  
Uriy A. Kublitsky ◽  
Dmitry A. Subetto ◽  
Anna V. Ludikova ◽  
Alar Rosentau ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Bottom Sediments ◽  
Modern Science ◽  
Karelian Isthmus ◽  
The Baltic Sea ◽  
Diatom Analysis ◽  
North West ◽  
The North ◽  
Important Direction ◽  
The Baltic

The study of paleogeography of lakes is an actual and important direction in modern science. As part of the study of lakes in the North-West of the Karelian Isthmus, this analysis will establish the dynamics of salinity of objects, which will allow to reconstruct changes in the level of the Baltic Sea in the Holocene.

Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III)

2008 ◽  
Vol 37 (4) ◽  
Author(s):  
Małgorzata Leśniewska ◽  
Małgorzata Witak
Keyword(s):  
Baltic Sea ◽  
The South ◽  
Gulf Of Gdańsk ◽  
The Baltic Sea ◽  
Southern Baltic Sea ◽  
Gulf Of Gdansk ◽  
Southern Baltic ◽  
The Baltic ◽  
Palaeoenvironmental Changes

Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III)The palaeoenvironmental changes of the south-western part of the Gulf of Gdańsk during the last 8,000 years, with reference to the stages of the Baltic Sea, were reconstructed. Diatom analyses of two cores taken from the shallower and deeper parts of the basin enabled the conclusion to be drawn that the microflora studied developed in the three Baltic phases: Mastogloia, Littorina and Post-Littorina. Moreover, the so-called anthropogenic assemblage was observed in subbottom sediments of the study area.

Associations of Sphagnum rubellum Wils. on the bogs of the south-east part of Baltic region

2003 ◽  
pp. 50-61 ◽  
Author(s):  
V. A. Smagin ◽  
M. G. Napreenko
Keyword(s):  
Baltic Sea ◽  
Plant Cover ◽  
Karelian Isthmus ◽  
Baltic Region ◽  
The South ◽  
The Baltic Sea ◽  
Kaliningrad Region ◽  
The Baltic ◽  
Typical Habitat ◽  
New Syntaxa

The paper characterizes the 3 associations comprising plant communities with Sphagnum rubellum in the south-eastern part of the Baltic region. The new syntaxa differ from each other both in their floristic characters and the pronounced affinity to definite regional mire types and particular habitats. The ass. Drosero-Sphagnetum rubelli is typical of the relatively most thorough ranges. It is observed from the Kaliningrad region to the Karelian Isthmus and, according to the published reference, occurs even throughout the whole area around the Baltic Sea. Its most typical habitat is that of margins of mire lakes and pools. The ass. Eriophoro-Sphagnetum rubelli occurs in central plateaus of convex plateau-like bogs, typical of the areas adjacent to the Baltic Sea coast. It occupies extended flat mire ecotopes with the water level 0.2–0.25 m deep. The ass. Empetro-Sphagnetum rubelli is characteristic of the retrogressive complex in the convex bogs of the East-Baltic Province. It is mostly observed along the coast of the Gulf of Finland. Its stands are rather dynamic and unstable in both space and time. The presence of communities comprised by these 3 associations is an important vegetation character of the series of regional mire types. Assuming an association level of the respective syntaxa seems rational for the purposes of adequate reflection of plant cover diversity.

Sign in / Sign up

Export Citation Format

Share Document