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Aquatic subsidies transport anthropogenic nitrogen to riparian spiders
2011
Akamatsu, Fumikazu | Toda, Hideshige
Stable nitrogen isotopic composition (δ¹⁵N) of aquatic biota increases with anthropogenic N inputs such as sewage and livestock waste downstream. Increase in δ¹⁵N of riparian spiders downstream may reflect the anthropogenic pollution exposure through predation on aquatic insects. A two-source mixing model based on stable carbon isotopic composition showed the greatest dependence on aquatic insects (84%) by horizontal web-building spiders, followed by intermediate (48%) and low (31%) dependence by cursorial and vertical web-building spiders, respectively. The spider body size was negatively correlated with the dietary proportion of aquatic insects and spider δ¹⁵N. The aquatic subsidies transported anthropogenic N to smaller riparian spiders downstream. This transport of anthropogenic N was regulated by spider’s guild designation and body size.
Показать больше [+] Меньше [-]The new potential invader Linopherus canariensis (Polychaeta: Amphinomidae) in a Mediterranean coastal lake: Colonization dynamics and morphological remarks
2011
Cosentino, A. | Giacobbe, S.
The newly introduced polychaete Linopherus canariensis Langerhans, 1881 was found in the Lake of Faro (NE Sicily), during a study comparing the macrobenthos in artificial modules with a neighboring sandy bottom assemblage. Of a total of 4465 specimens, almost 6% showed morphological variation related to branchial turfs and mean body size. The sandy bottom exhibited an average density of 41.86indL⁻¹ and a wet biomass of 30.35mgL⁻¹, whereas the artificial substratum reached levels of 205.29indL⁻¹ and 318.44mgL⁻¹. The highest estimated immigration rate was 3.7indL⁻¹d⁻¹ (5.8mgL⁻¹d⁻¹). In the artificial microhabitat, 0.4% of the population showed mid-anterior fragmentation, with anterior- (2%), mid- (<1%) and posterior- (1%) regenerating lineages, which contributed significantly to the dispersion ability of this species. L. canariensis was a selective micro-deposit feeder, even under conditions of reduced sediments. Linopherus was found to be a new potential invader of stressed environments that is probably tied to the import of oysters.
Показать больше [+] Меньше [-]Macrobenthic community response to copper in Shelter Island Yacht Basin, San Diego Bay, California
2011
Neira, Carlos | Mendoza, Guillermo | Levin, Lisa A. | Zirino, Alberto | Delgadillo-Hinojosa, Francisco | Porrachia, Magali | Deheyn, Dimitri D.
We examined Cu contamination effects on macrobenthic communities and Cu concentration in invertebrates within Shelter Island Yacht Basin, San Diego Bay, California. Results indicate that at some sites, Cu in sediment has exceeded a threshold for “self defense” mechanisms and highlight the potential negative impacts on benthic faunal communities where Cu accumulates and persists in sediments. At sites with elevated Cu levels in sediment, macrobenthic communities were not only less diverse but also their total biomass and body size (individual biomass) were reduced compared to sites with lower Cu. Cu concentration in tissue varied between species and within the same species, reflecting differing abilities to “regulate” their body load. The spatial complexity of Cu effects in a small marina such as SIYB emphasizes that sediment-quality criteria based solely on laboratory experiments should be used with caution, as they do not necessarily reflect the condition at the community and ecosystem levels.
Показать больше [+] Меньше [-]Ingestion of marine debris by loggerhead sea turtles, Caretta caretta, in the Adriatic Sea
2011
Lazar, Bojan | Gračan, Romana
We examined the occurrence of marine debris in the gastrointestinal tract of 54 loggerhead sea turtles (Caretta caretta) found stranded or incidentally captured dead by fisheries in the Adriatic Sea, with a curved carapace length of 25.0–79.2cm. Marine debris was present in 35.2% of turtles and included soft plastic, ropes, Styrofoam and monofilament lines found in 68.4%, 42.1%, 15.8% and 5.3% of loggerheads that have ingested debris, respectively. The dry mass of debris per turtle was low, ranging from <0.01 to 0.71g, and the ingestion was not significantly affected by sex or body size (all p>0.05). Marine debris averaged 2.2±8.0% of dry mass of gut content, with a maximum of 35% found in a juvenile turtle that most likely died due to debris ingestion. Considering the relatively high occurrence of debris intake and possible sub-lethal effects of even small quantities of marine debris, this can be an additional factor of concern for loggerheads in the Adriatic Sea.
Показать больше [+] Меньше [-]Seasonal size-frequency distribution of Norway lobster, Nephrops norvegicus (Linnaeus, 1758) in Montenegrin waters (South Adriatic) | Sezonska raspodela dužinskih frekvencija škampa, Nephrops norvegicus (Linnaeus, 1758) u vodama Crnogorskog primorja
2011
Kasalica, O., Institut za biologiju mora, Kotor (Montenegro) | Regner, S., Institut za multidisciplinarna istraživanja, Beograd (Serbia) | Ikica, Z., Institut za biologiju mora, Kotor (Montenegro) | Mandić, M., Institut za biologiju mora, Kotor (Montenegro)
In this paper the size-frequency distribution by sexes and for the whole sample of Norway lobster Nephrops norvegicus (Linnaeus, 1758) as well as the sex raio have been analyzed. Representative subsamples were collected during the four sesonally trawl surveys (summer 2009 – spring 2010) at depths from 330 to 350 m. Total number of analyzed individuals was 303. The carapace length (CL) of the all individuals ranged from 20 to 58mm while the female carapace length-range was 20-56mm and 22-58mm for males. in all seasons males were larger than females and highly represented in the catch in bigger size classes. The overall sex ratio during the investigation period was in favor of females (1.3:1).
Показать больше [+] Меньше [-]Biological and fisheries characteristics of red mullet (Mullus barbatus, L.) from the Montenegrin shelf | Ribarstveno-biološke karakteristike barbuna (Mullus barbatus, L.) na šelfu Crnogorskog primorja
2011
Mandić, M., Institut za biologiju mora, Kotor (Montenegro) | Pešić, A., Institut za biologiju mora, Kotor (Montenegro) | Đurović, M., Institut za biologiju mora, Kotor (Montenegro) | Joksimović, A., Institut za biologiju mora, Kotor (Montenegro) | Kasalica, O., Institut za biologiju mora, Kotor (Montenegro) | Ikica, Z., Institut za biologiju mora, Kotor (Montenegro)
The paper presents results of studies of biology and fisheries of red mullet (Mullus barbatus, L.) which was done within the frame of AdriaMed Trawl survey Project 2007/08. The Project encompassed monthly research of several target species in trawl fisheries of Montenegrin waters during one year in three most important fisheries ports in Montenegro (Bar, Budva and Herceg Novi). Total length of red mullet ranged from 9.1 to 21.5 cm with an average value of 15.1 cm. Length frequency distribution, length-weight relationship and sex ratio were analyzed.
Показать больше [+] Меньше [-]Length-weight relationship of the most common cephalopod species in Montenegrin trawl | Dužinsko-težinski odnos najzastupljenijih vrsta cephalopoda u kočarskom ribolovu na Crnogorskom primorju
2011
Ikica, Z., Institut za biologiju mora, Kotor (Montenegro) | Kasalica, O., Institut za biologiju mora, Kotor (Montenegro) | Mandić, M., Institut za biologiju mora, Kotor (Montenegro) | Đurović, M., Institut za biologiju mora, Kotor (Montenegro)
A length-weight relationship (LW) for five cephalopod species, of which three decapod (Illex coindetii, Loligo vulgaris, Sepia officianlis) and two octopod species (Eledone cirrhosa, Eledone moschata) is given in this paper. The mean exponent b was found to be significantly lower than 3.
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