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1
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Impact of conspecifics on recruitment and behaviour of Dreissena polymorpha (Pallas, 1771)

100%
Kobak J.
Folia Malacologica
|
2003
|
tom 11
|
nr 3-4
Behaviour of larvae, juveniles and adults of Dreissena polymorpha in the presence of the conspecifics was investigated in field and laboratory experiments. Mussel recruitment was studied in plastic chambers containing living conspecifics, their empty shells or calcareous, mussel-sized stones. The objects were glued to the chamber bottom and covered by nylon mesh. The experiment was carried out in the channel connecting the Port Zimowy harbour with the Vistula River (Toruń, Poland). Total mussel densities in the above treatments were the same as in the empty chambers. However, the distribution of the new settlers depended on the quality of the glued objects, with the vicinity of living mussels and empty shells being preferred to stones. This suggests that mussels responded to conspecifics after settling on substrate. Migration of juvenile and adult mussels in the presence of the same stimuli was then studied in a laboratory experiment. Both groups preferred the vicinity of living conspecifics, but any kind of the firmly attached objects decreased the number of individuals leaving the substrate, compared to the flat surfaces.
2
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Impact of light conditions on geotaxis behaviour of juvenile Dreissena polymorpha

100%
Kobak J.
Folia Malacologica
|
2002
|
tom 10
|
nr 2
Zebra mussel (Dreissena polymorpha) strongly affects aquatic ecosystems and underwater hydrotechnical equipment. In this study, movement direction of juvenile mussels (< 10 mm) was studied on a glass plate inclined against an aquarium wall (at angle of 16.5° to the bottom), or on the flat bottom, in various light conditions. In the darkness, the mussels exhibited a negative geotaxis, while in uniform light the numbers of specimens moving up and down the plate were similar. On the flat bottom, the mussels displayed a negative phototaxis. When only the upper part of the inclined plate was illuminated, most of the individuals moved downwards, indicating that light was a stronger signal than gravity. On the inclined plate with its lower part illuminated, more mussels moved upwards (like in the darkness), but this tendency was not statistically significant. Due to the observed behaviour, mussels could counteract adverse effects of conspecific competition by selecting sites on the top of a colony (due to the negative geotaxis in the darkness), and avoid dangers associated with water surface, such as increased probability of air exposure or predator attacks (due to the negative phototaxis in the light).
3

Osiadanie larw i sila przyczepu osobnikow doroslych racicznicy zmiennej [Dreissena polymorpha] na sztucznych podlozach

100%
Kobak J.
Idee Ekologiczne. Seria:Szkice
|
2003
|
tom 08s.66-69,rys.
66-69
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Factors affecting behaviour of settled individuals of the zebra mussel Dreissena polymorpha

75%
Kobak J.
Folia Malacologica
|
2010
|
tom 18
|
nr 3
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Effect of light on geotaxy of juvenile zebra mussels Dreissena polymarpha (Pallas, 1771)

75%
Kobak J.
Folia Malacologica
|
2002
|
tom 10
|
nr 1
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Impact of substratum type on attachment and survival of Dreissena polymorpha (Bivalvia)

63%
Kobak J., Januszewska M.
Folia Malacologica
|
2006
|
tom 14
|
nr 2
We studied the attachment strength of Dreissena polymorpha on nine artificial substrata in the laboratory. The highest attachment strength (0.46 N) was found on resocart (phenoplast plastic). It was lower on aluminium, acrylic, PVC, rubber and glass (listed in the order of decreasing strength), and the lowest on zinc, Penaten cream coating and copper. Apart from reducing adhesion, copper substratum caused also heavy mortality of the mussels. Further experiments, in which mussels were exposed on resocart surfaces in the presence of the examined materials (thus being influenced only by waterborne substances released by them), revealed that zinc and copper inhibited mussel attachment primarily by means of ions released to the water column. In the case of Penaten coating, the impact of its surface properties upon mussels seemed to be more important than waterborne cues.
7

Peculiarities of macrozoobenthos in the offshore zone of a small artificial post-gravel pit reservoir

63%
Zbikowski J., Kobak J.
Oceanological and Hydrobiological Studies
|
2010
|
tom 39
|
nr 1
39-59
8
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Does predator-induced behaviour protect the zebra mussel from roach?

63%
Kobak J., Kakareko T.
Folia Malacologica
|
2012
|
tom 20
|
nr 1
9

Relationships between the occurrence of Chaetogammarus ischnus [Stebbing, 1898] and Pontogammarus robustoides [G.O. Sars, 1894] [Crustacea, Amphipoda] in a lowland Polish dam reservoir

63%
Zytkowicz J., Kobak J.
Oceanological and Hydrobiological Studies
|
2008
|
tom 37
|
nr 2
39-50
10
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Environmental factors modifying reactions of Dreissena polymorpha to alarm substances

63%
Kobak J., Rynska A.
Folia Malacologica
|
2015
|
tom 23
|
nr 1
11
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The effect of abiotic factors on aggregating of the zebra mussel Dreissena polymorpha

63%
Kobak J., Tosenovsky E.
Folia Malacologica
|
2016
|
tom 24
|
nr 1
12

First report on the importance of alien gobiids in the diet of native piscivorous fishes in the lower Vistula River (Poland)

51%
Plachocki D., Kobak J., Kakareko T.
Oceanological and Hydrobiological Studies
|
2012
|
tom 41
|
nr 2
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Mechanisms of effect of copper substratum on the adhesion, intensity of migration and mortality of the zebra mussels (Dreissena polymarpha (Pallas, 1771))

51%
Kobak J., Klosowska-Mikulan E., Wisniewski R.
Folia Malacologica
|
2002
|
tom 10
|
nr 1
14
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Malacofauna of two hydrologically different habitats in the near-shore zone of the Wloclawek dam reservoir (Vistula River, Poland)

51%
Zbikowski J., Kakareko T., Poznanska M., Kobak J.
Folia Malacologica
|
2007
|
tom 15
|
nr 1
We studied molluscan fauna at two sites in the W³oc³awek Dam Reservoir, differing with respect to the hydrological conditions: a rheolimnic site with a comparatively strong water flow (Soczewka) and a limnetic site, dominated by wave action (Dobiegniewo). Within each site, we sampled molluscs from three substratum types (sand, a thin layer of mud on sand and mud). Samples were collected monthly, from April to October. The taxonomic composition differed between the sites, with Sphaerium corneum (L. 1758), Pisidium sp. C. Pfeiffer, 1821, Bithynia tentaculata (L. 1758) and Viviparus viviparus (L. 1758) being more abundant in Soczewka, while Potamopyrgus antipodarum (Gray, 1843), Marstoniopsis scholtzi (Schmidt, 1856) and Dreissena polymorpha (Pallas 1771) occurred exclusively in Dobiegniewo. S. corneum was a strong dominant in most of the samples, and variation in its abundance was the only cause of the observed differences among the various substrata. Strong differences in the total density and biomass were also observed between the two sites, the molluscs from Soczewka being much more abundant. This phenomenon was particularly apparent on the muddy substratum, which was the most suitable in Soczewka and the poorest in Dobiegniewo. Our study revealed that moderate water flow in Soczewka affected molluscs by improving conditions for them, especially on the muddy substratum.
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Preferences of ponto-caspian and native amphipods to zebra mussel Dreissena polymorpha

51%
Kobak J., Poznanska M., Kakareko T.
Folia Malacologica
|
2010
|
tom 18
|
nr 3
16

Morphometric characteristics of the small and large intestines of Mus musculus during postnatal development

51%
Wolczuk K., Wilczynska B., Jaroszewska M., Kobak J.
Folia Morphologica
|
2011
|
tom 70
|
nr 4
The objective of this study was to investigate the size of the small and large intestine in postnatal development of Mus musculus mice. The gut was obtained from 2-, 4-, 6-, and 12-week-old animals. The morphometric analysis was performed at microscopic level. Measurements and calculations included dimensions of villi (height, diameter) and their number per 1 mm² surface area in the proximal, middle, and distal section of the small intestine, as well as the length and surface area (external and internal) of the small and large intestines. To find the allometric relationship between the size of the small and large intestines and body mass, reduced major axis regression was applied. The length and surface area of both intestinal segments gradually increased with age. The increase in the internal surface area of the small intestine was the result of lengthening of the intestine and increasing diameter of the villi in its proximal and middle sections. No increase in villus height during the studied period was detected. A marked increase in the size of the intestinal segments was observed between the 2nd and 4th weeks of life, when the length doubled and the surface area tripled in size. Allometric analysis revealed that the increase in length and internal surface area of the small and large intestines was more rapid than the body mass increase during the weaning period, while it was not different from isometry after the weaning. In conclusion, the greatest changes in the structure and size of the small and large intestines of mice occurred in the weaning period. During this period these two segments of intestine grew faster than the rest of the body and reached adult proportions. (Folia Morphol 2011; 70, 4: 252–259)
17
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Content available

Mineral shell components in Cepaea nemoralis (L.): differences between colour morphs and relations with structural shell characters

51%
Rosin Z. M., Lesicki A., Tryjanowski P., Kobak J.
Folia Malacologica
|
2016
|
tom 24
|
nr 1
18
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The effect of kairomones of the roach Rutilus rutilus on the movements of the zebra mussel Dreissena polymorpha

51%
Zielska J., Dzierzynska-Bialonczyk A., Kobak J.
Folia Malacologica
|
2016
|
tom 24
|
nr 1
19
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The effect of conspecific individuals on the locomotion of the zebra mussel Dreissena polymorpha

51%
Dzierzynska-Bialonczyk A., Skrzypczak A., Kobak J.
Folia Malacologica
|
2016
|
tom 24
|
nr 1
20
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Content available

Impact of copper substrate on survival, mobility and attachment strength of adult Dreissena polymorpha (Pall.)

51%
Kobak J., Klosowska-Mikulan E., Wisniewski R.
Folia Malacologica
|
2002
|
tom 10
|
nr 2
Zebra mussels were tested for their mobility and strength of attachment in six diferent experimental combinations. They were kept for 7 days on copper or plastic (phenoplast) plates in 4-L beakers put on the bottom, or on plastic (resocart) plates suspended 15 mm above copper ones; water used was pure or with addition of a metal ion chelator - disodium versenate (EDTA). Exposure to copper ions resulted in the highest mortality. When the ions were EDTA-removed, the animals tended to leave copper plates and stay on the glass bottom or walls of the beakers. Attachment strength was measured with a device based on pan scales, with one of the pans replaced by forceps grasping a mussel. It was significantly lower in the presence of copper ions or with metallic substrate. Both the release of ions and the surface properties of copper substrate were found to influence zebra mussels, the former factor increasing their mortality, the latter causing sublethal responses. The observations may be useful in designing fouling-resistant devices and systems.
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