A generalized, nonlinear regression approach to the length-weight relationship of European perch (Perca fluviatilis L.) from the Polish coast of the southern Baltic Sea

Abstract Length-weight relationships in fish are important tools in fisheries management. The aim of this study was to estimate the growth curve W=aLb for European perch, Perca fluviatilis L., from the Polish coast of the southern Baltic Sea (ICES Subdivision 25). The data set comprised the total weights and total lengths of 827 specimens caught during the 2011-2013 period. The mean total length (TL) was 169.4 mm (range 100.0-310.0 mm), and the mean total weight was 83.9 g (range 11.3-553.2 g). First, a multiplicative error term and a linear regression approach to loglog-transformed data was considered. The following estimated values for the parameters were obtained: a = exp(-12.5323), b=3.25, s=0.07862. This approach was not successful in solving the common heterogeneity problem of the length-weight data. A generalized nonlinear regression approach to the original data was more suitable in our case. The estimated model was W = 3.83×10-6×L3.238 + ε, with ε~norm(0,0.0281×E[W|L]2×1.242). The estimated 95% confidence interval for b was (3.218, 3.259), and the growth was allometric. The perch from the coastal waters of the Baltic Sea (ICES Subdivision 25) was characterized by slightly better condition than that caught in inland waters and estuaries.

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Adult female European perch (Perca fluviatilis) from the Baltic Sea show no evidence of thiamine deficiency

Journal of Sea Research ◽

10.1016/j.seares.2021.102081 ◽

2021 ◽

pp. 102081

Author(s):

Johan Gustafsson ◽

Karin Ström ◽

Linus Arvstrand ◽

Lars Förlin ◽

Lillemor Asplund ◽

...

Keyword(s):

Baltic Sea ◽

Adult Female ◽

Thiamine Deficiency ◽

Perca Fluviatilis ◽

The Baltic Sea ◽

European Perch ◽

Perch Perca Fluviatilis ◽

The Baltic

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Composition of protozoan communities at two sites in the coastal zone of the southern Baltic Sea

Oceanological and Hydrobiological Studies ◽

10.2478/s13545-013-0083-x ◽

2013 ◽

Vol 42 (3) ◽

Cited By ~ 3

Author(s):

Krzysztof Rychert ◽

Katarzyna Spich ◽

Kinga Laskus ◽

Michalina Pączkowska ◽

Magdalena Wielgat-Rychert ◽

...

Keyword(s):

Baltic Sea ◽

Coastal Zone ◽

Seasonal Changes ◽

Sampling Site ◽

Heterotrophic Nanoflagellates ◽

Southern Baltic Sea ◽

Protozoan Community ◽

Annual Biomass ◽

The Mean ◽

Southern Baltic

AbstractProtozoan communities were studied in the coastal zone of the southern Baltic Sea. Stable environmental conditions and typical, bimodal seasonal changes in the protozoan biomass were observed at the sampling site in Sopot (2003–2004). At the sampling site in Ustka (2007–2008), strong benthic resuspension and irregular impacts of fresh water resulted in atypical seasonal changes in the protozoan biomass with a summer peak only. The mean annual biomass had similar values at both sites: 43.2 μg C dm−3 in Sopot and 38.6 μg C dm−3 in Ustka. The protozoan community in Sopot was dominated by ciliates (48% of the biomass), whereas in Ustka — by heterotrophic nanoflagellates (53%).

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Influence ofTriaenophorus nodulosusplerocercoids (Cestoda: Pseudophyllidea) on the occurrence of intestinal helminths in the perch (Perca fluviatilis)

Journal of Helminthology ◽

10.1017/s0022149x16000870 ◽

2017 ◽

Vol 91 (6) ◽

pp. 711-717 ◽

Cited By ~ 2

Author(s):

N.J. Morley ◽

J.W. Lewis

Keyword(s):

Perca Fluviatilis ◽

Helminth Species ◽

Intestinal Helminths ◽

European Perch ◽

Perch Perca Fluviatilis ◽

Wide Range ◽

Concurrent Infections ◽

Acanthocephalus Lucii ◽

The Mean ◽

Triaenophorus Nodulosus

AbstractConcurrent infections of helminths in vertebrates are widespread and may demonstrate synergistic, antagonistic or negligible levels of interactions between species that share a common site. However, indirect interactions between species that occur in different organs of a host are poorly documented, particularly in fish. Plerocercoids ofTriaenophorus nodulosusare common liver infections of European perch (Perca fluviatilis). These larval cestodes cause extensive liver damage, resulting in systemic pathologies that include alteration of the physiochemical environment of the intestine. Perch harbour a wide range of intestinal helminths whose occurrence may be potentially influenced by the concurrent presence ofT. nodulosusplerocercoids. The present study, using an existing dataset, investigated the effects ofT. nodulosuson the infection levels of four common perch helminths –Acanthocephalus lucii, Camallanus lacustris, Proteocephalus percaeandBunodera luciopercae. The prevalences ofA. luciiandC. lacustriswere significantly reduced in fish infected byT. nodulosus, although the mean intensity of infections remained unaffected for any helminth species, while the mean abundance ofC. lacustriswas significantly reduced in plerocercoid-affected perch. Differences in site selection and individual interactions between the four helminth species in the intestine ofT. nodulosus-infected and non-infected perch were rarely observed.

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

Oceanological and Hydrobiological Studies ◽

10.2478/v10009-008-0017-x ◽

2008 ◽

Vol 37 (4) ◽

Cited By ~ 6

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.

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