Short feeding migration associated with a lower mean size of whitefish in the River Tornionjoki, northern Baltic Sea

2018 ◽  
Vol 25 (4) ◽  
pp. 261-266 ◽  
Author(s):  
Erkki Jokikokko ◽  
Henry Hägerstrand ◽  
Jan-Olof Lill
2014 ◽  
Vol 48 (23) ◽  
pp. 13969-13977 ◽  
Author(s):  
Mirella Kanerva ◽  
Anni Vehmas ◽  
Mikko Nikinmaa ◽  
Kristiina A. Vuori

2006 ◽  
Vol 63 (8) ◽  
pp. 1477-1487 ◽  
Author(s):  
Antti Siira ◽  
Petri Suuronen ◽  
Petri Kreivi ◽  
Jaakko Erkinaro

Abstract We estimated the total size of the Atlantic salmon (Salmo salar) population complex (wild and cultured) in the Gulf of Bothnia, northern Baltic Sea, using a stratified mark-recapture method. In 2001 and 2002, 1970 salmon were captured by the commercial trapnet fishery and tagged with external arrow tags. A total of 349 tagged fish was later recaptured among 65 180 salmon screened for tags. Recoveries were gathered by the commercial trapnets and by screening fish entering counting facilities in rivers and broodstock fisheries at the river mouths. In addition, tags were recovered from recreational river catches. Our estimates suggest that the total size of the migrating population in both years was about 230 000 fish. Proportions of wild and cultured salmon differed between the two years. In 2001, the proportion of wild salmon was 37%; the corresponding figure for 2002 was 62%. Based on estimates of wild salmon smolt production and the number of released smolts, the estimated proportion of cultured smolts that survived the feeding migration and returned to the Gulf of Bothnia (2–4%) was approximately 2.5–4.5 times lower than that of wild smolts (9–10%).


2016 ◽  
Vol 26 (3) ◽  
pp. 456-461 ◽  
Author(s):  
Henry Hägerstrand ◽  
Yvette Heimbrand ◽  
Mikael von Numers ◽  
Jan-Olof Lill ◽  
Erkki Jokikokko ◽  
...  

Author(s):  
S. Laoussadi ◽  
A. Kahan ◽  
G. Aubouy ◽  
F. Delbarre

Several patients with Fabry's, Gaucher's diseases and hyperlipoproteinemia type II and with arthropatic manifestations were observed.As no histological explanation for these symptoms was available,an ultrastructural study of synovial tissue was done to establish an anatomoclinical relation.Material and Methods :synovial membrane samples were obtained by needle biopsies of the knee from three patients with arthropatic manifestations of each disease.They were fixed in 5% glutaraldehyde, postfixed in 1% osmium tetraoxyde and embedded in Epon 812. Thin sections coloured by uranyl acetate and lead citrate were observed with an Elmiskop I Siemens electron microscope.Two important phenomena were observed in synovial tissue:Specific patterns of each lipid storage disease,which are now well known.In all the three metabolic diseases, hydroxyapatite-like crystals were found. They are characterized by their intramitochondrial localization, without any relation with cristae,an anarchic disposition and a mean size of 550 A.Crystals may be found also free in the cytoplasm of synoviocytes Some micrographs suggest an evolution in four steps :a. mitochondria with only a few microcrystalsb. mitochondria stuffed with these structuresc. disruption of mitochondria membranesd. microcrystals appear free in the cytoplasm


Boreas ◽  
2002 ◽  
Vol 31 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Christian Christiansen ◽  
Helmar Kunzendorf ◽  
Kay-Christian Emeis ◽  
Rudolf Endler ◽  
Ulrich Struck ◽  
...  

2003 ◽  
pp. 136-146
Author(s):  
K. Liuhto

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.


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