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1
Content available Impact of Chinese mitten crab Eriocheir sinensis on blue mussel Mytilus edulis trossulus – laboratory studies of claw strength, handling behavior, consumption rate, and size selective predation
Wójcik D., Normant M., Dmochowska B., Fowler A.
Oceanologia
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2015
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No. 57 (3)
263--270
EN
We examined the claw strength, handling behavior, consumption rate, and size selective predation of the invasive Chinese mitten crab Eriocheir sinensis feeding on native Baltic Sea blue mussels Mytilus edulis trossulus during 24 h laboratory experiments. Single starved crabs were offered 15 mussels (five mussels in three length classes) at a time. The total number of mussels consumed by a single crab increased significantly (P < 0.05) with the experimental time from 1.7 ± 0.7 # mussels crab−1 h−1 after 4 h to 0.2 ± 0.7 # mussels crab−1 h−1 after 24 h. The highest consumption rate was observed within the first 4 h, and it decreased significantly (P < 0.05) during the experiment. This was most likely due to the crabs being starved before the start of the experiment. E. sinensis can also harm blue mussel shells by crushing them without further consumption. The mean daily damage, and not consumption, by a single crab was 0.9 ± 1.4 of 11–40 mm mussels. The claw strength of E. sinensis ranged from 1.50 to 20.43 N (mean 8.51 ± 5.93 N) and was significantly correlated (P < 0.05) with sex and both claw size and carapace size. The study showed that E. sinensis may be able to impact the native M. edulis trossulus population abundance in the coastal Baltic waters either through direct predation or indirect mortality by damaging (crushing) the shell.
2
Content available remote Effect of temperature on physiology and bioenergetics of adult Harris mud crab Rhithropanopeus harrisii (Gould, 1841) from the southern Baltic Sea
Hegele-Drywa J., Normant M.
Oceanological and Hydrobiological Studies
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2014
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Vol. 43, No. 3
219--227
EN
Rates of physiological processes and bioenergetics of the Harris mud crab Rhithropanopeus harrisii were determined during a 7-day experiment on adult males (mean wet weight 0.83 ± 0.16 g) exposed to temperatures of 15°C and 20°C (S = 7). The results show that the change in temperature by 5°C caused detectable changes in locomotor activity, food consumption and faeces production and significant (p < 0.05) changes in metabolic rates. Food assimilation efficiency and the ammonia excretion rate did not change significantly (p > 0.05). The energy expended on metabolic processes was similar at both temperatures (15°C and 20°C) and amounted to 17.7 ± 6.4% and 16.7 ± 4.3% of the assimilated energy, respectively. Similar values were obtained for net production efficiency K2 (P/A) at 15°C and 20°C, i.e. 80.4 ± 22.4% and 82.9 ± 9.7%, respectively. The amount of energy available for production was 2-fold higher at a temperature of 20°C than at 15°C and amounted to 103.69 ± 25.61 and 206.40 ± 20.76 J d−1g−1 wet wt, respectively. The results show that from the bioenergetic point of view, higher experimental temperature is more “profitable” for adult R. harrisii specimens because it provides better conditions for the growth and reproduction.
3
Content available remote Population structure, morphometry and individual condition of the non-native crab Rhithropanopeus harrisii (Gould, 1841), a recent coloniser of the Gulf of Gdańsk (southern Baltic Sea)
Hegele-Drywa J., Normant M., Szwarc B., Podłuska A.
Oceanologia
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2014
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No. 56 (4)
805--824
EN
The aim of this study was to characterise the introduced North American Harris mud crab Rhithropanopeus harrisii, which occurs in the Gulf of Gdańsk, Poland (southern Baltic Sea). Of the 920 specimens caught between 2006 and 2010, males and females made up 44 and 40% respectively, whereas juveniles (<4.4 mm carapace width) comprised 16%. Overall carapace widths ranged from 1.96 mm to 21.40 mm (mean 9.03±4.11 mm). Ovigerous females (mean 11.12±2.76 mm) were present in the population from June to October. Most of the adult specimens collected (n = 158) had carapace widths between 10.1 and 12.0 mm. The wet weight of R. harrisii varied from 0.005 to 4.446 g (mean 0.410±0.569 g). Females exhibited a negative allometric increase in weight (b = 2.77), males an isometric increase in weight (b = 3.02). The condition factor (K) in R. harrisii varied from 0.02 to 0.08 (mean 0.05±0.01).
4
Content available remote Non-native crab Rhithropanopeus harrisii (Gould, 1984) - a new component of the benthic communities in the Gulf of Gdańsk (southern Baltic Sea)
Hegele-Drywa J., Normant M.
Oceanologia
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2014
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No. 56 (1)
125--139
EN
The aim of this study was to determine the occurrence, spatial distribution and abundance pattern of the Harris mud crab Rhithropanopeus harrisii in the Gulf of Gdańsk (southern Baltic Sea). Between 2006 and 2010, this species was found at 69 out of 129 sampling stations, at depths from 0 to 20 m. Two main aggregations of the Harris mud crab were established: (1) in Puck Bay (max. density 19 indiv. 100 m-2) and (2) in the Gdynia and Sopot area (max. density 5 indiv. 100 m-2). 920 specimens were collected during the whole sampling period: 150 juveniles, 370 females and 400 males. The minimum measured carapace width was 1.96 mm, the maximum 21.40 mm (mean 9.03 ±4.11 mm).
5
Content available remote Gonad maturity in female Chinese mitten crab Eriocheir sinensis from the southern Baltic Sea : the first description of ovigerous females and the embryo developmental stage
Wójcik D., Normant M.
Oceanologia
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2014
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No. 56 (4)
779--789
EN
This paper describes for the first time the gonad maturity stage of Eriocheir sinensis females (carapace width 55.20-78.10 mm) collected in the autumns and winters of 2005–2012 in the Gulf of Gdańsk and Vistula Lagoon (southern Baltic Sea). Seventeen females had gonads in the penultimate stage, which indicates that spawning would shortly take place. Four other females had gonads in the last stage, which means they were already carrying eggs. These accounted, on average, for 17.9± 2.9% of female weight and were in the 3rd and 4th embryo developmental stage. The results show that the low salinity of southern Baltic Sea (≤7 PSU) permits mating and fertilization as well as embryo development in E. sinensis. It is still not clear, whether such a salinity level will enable hatching and the complete larval cycle.
6
Content available remote Epibiotic mites associated with the invasive Chinese mitten crab Eriocheir sinensis : new records of Halacaridae from Poland
Normant M., Zawal A., Chatterjee T., Wójcik D.
Oceanologia
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2013
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No. 55 (4)
901--915
EN
Seven epibiotic halacarid mites (Caspihalacarus hyrcanus, two species of Copidognathus, Halacarellus petiti, Porohalacarus alpinus, Soldanellonyx monardi and S. chappuisi), two oribatid mites (Hydrozetes lacustris and Trhypochthoniellus longisetus) and one water mite (Piona pusilla) were found on the setae-covered claws of eighteen Chinese mitten crabs (Eriocheir sinensis) collected from fresh and brackish waters in Poland and Germany. The most abundant of the 111 mite individuals recorded was one of the Copidognathus species (N = 52); this was followed by H. petiti (N = 38) and C. hyrcanus (N = 13). This is the first record of H. petiti and of the genus Copidognathus from Polish waters. The possibility of migrating over long distances assisted by catadromous mitten crabs enhances mite dispersal, as well as their introduction to new environments.
7
Content available remote Epibiota associated with setae on Chinese mitten crab claws Eriocheir sinensis H. Milne-Edwards, 1853): a first record [commun.]
Normant M., Korthals J., Szaniawska A.
Oceanologia
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2007
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No. 49 (1)
137-143
EN
Eriocheir sinensis H. Milne-Edwards, 1853 is a non-native species found in European waters. Analyses of mitten crabs caught in brackish waters (Gulf of Gdańsk, Poland) and in freshwater (Havel River, Germany) have indicated that numerous epibionts (possibly temporary) inhabit the dense setal mats that cover the chelipeds. Of the 950 associates found on 22 crabs collected from brackish water, the most abundant were Nematoda (82.3%), followed by Bivalvia (10.3%), Crustacea (5.6%), Oligochaeta (1.2%) and Gastropoda (0.6%). In comparison, 1280 specimens (Chironomidae - 67.6% and Halacaridae - 32.4%), were identified from 13 crabs collected in freshwater. As this crab can migrate long distances, it is capable of transporting native and non-native species via its mittened claws to new habitats.
8
Content available remote Gammarus tigrinus Sexton 1939 (Crustacea, Amphipoda) - a new immigrant in the Puck Bay, southern Baltic Sea
Szaniawska A., Normant M., Łapucki T.
Oceanological and Hydrobiological Studies
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2005
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Vol. 34, No.2
71--78
EN
This study deals with the occurrence and migration of Gammarus tigrinus Sexton 1939 into the Puck Bay (western part of the Gulf of Gdansk, Baltic Sea). The material was collected in September 2002 at nine stations (approximate depth – 0.4 m). The only Gammarus species found at five sampling stations was G. tigrinus. The species found at other stations located along the inner part of the Puck Bay were G. salinus, G. zaddachi, and G. duebeni. The sex ratio for G. tigrinus was close to 1. Almost 50% of the females were carrying eggs. The males were larger (6.0 š 0.8 mm) than females (4.7 š 0.8 mm). The average male dry weight was 2.5 š 1.2 mg and that of females was 2.1 š 0.7 mg. The relation between length (L) and dry weight (DW) was DW = 0.095źL1.76 (R2 = 0.76). This study indicates that G. tigrinus is spreading rapidly in the Baltic Sea.
9
Content available remote The first record of parasites in Gammarus tigrinus Sexton, 1939 - a recent newcomer to the Gulf of Gdańsk [commun.]
Rolbiecki L., Normant M.
Oceanologia
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2005
|
No. 47 (2)
283-287
EN
The present paper reports for the first time on the occurrence of the parasite Maritrema subdolum in the amphipod Gammarus tigrinus, a non-native species in the Gulf of Gdańsk.
10
Content available remote Remarks on the morphology and the life cycle of Rhithropanopeus harrisii ssp tridentatus (maitland) from the dead Vistula River
Normant M., Miernik J., Szaniawska A.
Oceanological and Hydrobiological Studies
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2004
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Vol. 33, No. 4
93--102
EN
The aim of this study was to characterize the mud crab Rhithropanopeus harrisii ssp. tridentatus that occurs in the Dead Vistula. Of the 220 specimens collected, 57% were males and 43% were females. Females with eggs on the pleopods were present throughout June, July and August. The carapace width varied from 4.9 mm to 22.4 mm and length ranged from 4.1 mm to 16.3 mm. The highest frequency (49.1%) was observed in the 9.1-13.5 mm width class. The wet weight of the specimens varied from 0.045 to 4.299 g. The results obtained indicate that no significant changes in the morphology or life cycle of the R. harrisii tridentatus from the Dead Vistula River have occurred in the last 30 years.
11
Content available remote The invasive amphipod Gammarus tigrinus Sexton, 1939, in Puck Bay [commun.]
Szaniawska A., Łapucki T., Normant M.
Oceanologia
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2003
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No. 45 (3)
507-510
EN
The paper is a report on the occurrence of the species Gammarus tigrinus Sexton, 1939, in the coastal waters of Puck Bay.
12
Content available remote The Chinese mitten crab Eriocheir sinensis - an immigrant from Asia in the Gulf of Gdańsk [commun.]
Normant M., Chrobak M., Skóra K.
Oceanologia
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2002
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No. 44 (1)
123-125
EN
The present paper reports the occurrence of the Chinese mitten crab Eriocheir sinensis H. Milne Edwards, 1854 in the coastal waters of the Gulf of Gdansk, and attempts an initial characterization of the crabs occurring in this area.
13
Content available remote The Chinese mitten crab Eriocheir sinensis (Decapoda: Grapsidae) from Polish waters [commun.]
Normant M., Wiszniewska J., Szaniawska A.
Oceanologia
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2000
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No. 42 (3)
375-383
EN
The Chinese mitten crab Eriocheir sinensis Milne-Edwards, 1854 is a newcomer to the Baltic Sea. Previous studies have shown that since the 1940s single large specimens of this species have been caught annually in Polish waters. The invasion of the Chinese mitten crab has been reported from many European countries, including Poland, where it is especially abundant in the Odra Estuary. Of 186 specimens captured in Lake Dabie in August 1998, 45% were females and 55\% males. The carapace width of these crabs varied between 53 and 88 mm and the average wet weight was 169 š 45.3 g.
14
Content available remote The biochemical composition of Enteromorpha spp. from the Gulf of Gdansk coast on the southern Baltic Sea
Haroon A. M., Szaniawska A., Normant M., Janas U.
Oceanologia
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2000
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No. 42 (1)
19-28
EN
Variations in lipid, protein and carbohydrate contents of Enteromorpha spp. were examined over a seven-month period from April to October 1993. The samples were collected from seven sampling stations along the Gulf of Gda/nsk coast. The lipid content was low and varied slightly from 3.47 š 1.76% of DW at Puck to 4.36 š 2.17% of DW at Rewa and Cha/lupy. The protein content varied from 9.42 š 4.62% of DW at Puck to 20.60 š 5.00% of DW at Jurata. At the remaining stations the values vary over a narrow range. The maximum protein contents were recorded at the beginning and end of the growing season. The level of carbohydrate was very high compared to that of lipid and protein and varied from 29.09 š 6.44% of DW at Oslonino to 39.81 š 11.15% of DW at Puck. Seasonal carbohydrate changes were noted at all sampling stations, the minimum occurring in spring and autumn and the maximum in summer.
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