scholarly journals Does the Invasive Predator Mnemiopsis leidyi A. Agassiz, 1868 Control Copepod Abundances in the Seine Estuary?

2021 ◽  
Vol 4 (1) ◽  
Keyword(s):  
Spatial Distribution ◽  
Coastal Waters ◽  
Mnemiopsis Leidyi ◽  
Seine Estuary ◽  
English Channel ◽  
Western Atlantic ◽  
Dramatic Decline ◽  
Pleurobrachia Pileus ◽  
Negative Effect ◽  
First Time

The indigenous ctenophore Pleurobrachia pileus (O.F. Müller, 1776) was common in the coastal waters of the English Channel in the early 1990s and showed very abundant populations in the downstream part of the Seine estuary. In 2005, the non-indigenous ctenophore Mnemiopsis leidyi A. Agassiz, 1868, a species native to the Western Atlantic, was reported for the first time in Europe in Norwegian fjords and in Le Havre harbour (Seine estuary, France). More recently, in 2017, both Pleurobrachia pileus and Mnemiopsis leidyi were recorded during suprabenthos and zooplankton sampling in the Seine estuary along a downstream-upstream transect. Both species show more abundant populations in May than in September. Conversely, copepods show a spatial distribution depending on the ctenophore distribution, with low copepod abundances in the downstream part of the estuary being associated with high ctenophore abundances, while high copepod abundances are recorded where ctenophores are absent or display low abundances. We propose that the intense predation of ctenophores on copepods is related to changes in hydrological conditions over the two last decades. This may explain the dramatic decline of copepod abundance in the Seine estuary, which could have a negative effect on its nursery role.

Distribution of the Cirratulid Polychaetes Dodecaceria Fimbriata, D. Concharum and D. Diceria in European Waters Between Latitudes 48°N and 70°N

1996 ◽  
Vol 76 (3) ◽  
pp. 625-635 ◽  
Author(s):  
Peter H. Gibson
Keyword(s):  
North Sea ◽  
Coastal Waters ◽  
Northern Europe ◽  
English Channel ◽  
The North ◽  
The North Sea ◽  
Firth Of Forth ◽  
First Time

The distribution of Dodecaceria in northern Europe was found for samples borrowed from museums and other collections. Dodecaceria fimbriata was present in the coastal waters of mainland Britain and the Continent from the English Channel northwards. Dodecaceria concharum was only found in British mainland coastal waters and on the French coast at the western end of the English Channel. It was absent where salinities were below ~34%0. The two species were sampled along the Lothian and Borders coasts and the numbers of D. concharum fell with decreasing salinity as the Firth of Forth was approached. Dodecaceria diceria was found for the first time in the North Sea at depths of 100–200 m. The benthic salinity here is ~35%0.

scholarly journals First detection of Mnemiopsis leidyi (Ctenophora, Bolinopsidae) in Sardinia (S’Ena Arrubia Lagoon, Western Mediterranean): a threat for local fishery and species recruitment

2016 ◽  
Vol 17 (3) ◽  
pp. 714 ◽  
Author(s):  
R. DICIOTTI ◽  
J. CULURGIONI ◽  
S. SERRA ◽  
M. TRENTADUE ◽  
G. CHESSA ◽  
...  
Keyword(s):  
Management Strategies ◽  
Anguilla Anguilla ◽  
Western Mediterranean ◽  
Economic Damage ◽  
Mnemiopsis Leidyi ◽  
European Eel ◽  
Fishing Activity ◽  
Western Atlantic ◽  
Management Measures ◽  
First Time

The invasive comb jelly Mnemiopsis leidyi is a lobate ctenophore native of coastal and estuarine waters of the temperate western Atlantic Ocean. In the last decades this species has expanded its range of distribution, colonizing marine and transitional environments in Europe. In October 2015, during a survey fishing the European eel Anguilla anguilla in Sardinia (western Mediterranean), a massive bloom of this specie was observed in the eutrophic S’Ena Arrubia Lagoon for the first time. In November 2015, sampling was conducted at three stations in the lagoon and in a fyke net, in order to estimate the abundance of M. leidyi and to determine its impact on the fishing activity. The results showed an abundance of 2.83 ctenophores m-3. Specimens were all adults, measuring 18 - 62 mm total length. The abundant number of ctenophores (6837 individuals per fyke net) damaged fishing operations, reducing catches and affecting the performance of fishing gears. Since there is no effective mechanical, chemical or biological method to counter M. leidyi, the short term economic damage may be approached by new management measures of fisheries. In addition, other actions against the recurring of M. leidyi invasion, can include management strategies, in particular those finalized to reduce the high trophic state of the lagoon. 

Notes on the benthic marine algae of Puerto Rico. XII: additions to the flora

2019 ◽  
Vol 62 (4) ◽  
pp. 337-344 ◽  
Author(s):  
David L. Ballantine ◽  
Hector Ruíz ◽  
James N. Norris
Keyword(s):  
Puerto Rico ◽  
Coastal Waters ◽  
Marine Algae ◽  
Caribbean Sea ◽  
Western Atlantic ◽  
First Time ◽  
New Distribution

Abstract Five species of benthic marine algae (Phaeophyceae: Lobophora littlerorum; Rhodophyta: Meristotheca cylindrica, Naccaria corymbosa, Xiphosiphonia pinnulata and Dipterosiphonia reversa) represent new distribution records from the coastal waters surrounding Puerto Rico in the northern Caribbean Sea. The latter two species are now reported for the first time from the western Atlantic Caribbean.

First Record of the American Jack Knife Clam Ensis Directus on the French Coast of the North Sea

1993 ◽  
Vol 73 (1) ◽  
pp. 233-235 ◽  
Author(s):  
C. Luczak ◽  
J.-M. Dewarumez ◽  
K. Essink
Keyword(s):  
North Sea ◽  
Coastal Waters ◽  
New Records ◽  
First Record ◽  
English Channel ◽  
Southern Bight ◽  
The North ◽  
German Coast ◽  
The North Sea ◽  
First Time

Ensis directus (Bivalvia: Solenidae) was noted for the first time along the French coast of the North Sea in June 1991. High numbers of post larvae after a period of northerly winds indicate that settled larvae originated from adult populations in Belgian or Dutch coastal waters. Future dispersal of Ensis directus could be used as a biological tracer of coastal water movements between the Southern Bight of the North Sea and the English Channel.The American jack knife clam, Ensis directus (Conrad, 1843), synonym Ensis americanus (Binney, 1870)sensu van Urk (1964,1972), was discovered in Europe in the German Bight for the first time in June 1979 (Von Cosel et al., 1982). This species is assumed to have been transported in its larval stage by a ship containing ballast water. Considering the dimensions of the specimens, this probably happened in the first half of 1978 (Von Cosel et al., 1982; Mühlenhardt-Siegel et al., 1983). Since then this species has spread rapidly in the North Sea in subtidal and intertidal areas. Dense populations were found along the German coast within a few years (Von Cosel et al., 1982; Mühlenhardt-Siegel et al., 1983; Swennen et al., 1985). In 1986 Ensis directus was reported from the north and east Danish coasts as far as the Belgian coast (Kerkhof & Dumoulin, 1987) (Figure 1). Since then no new records have been reported.

High diversity of dinoflagellates in the intertidal sandy sediments of Wimereux (north-east English Channel, France)

2013 ◽  
Vol 94 (3) ◽  
pp. 443-457 ◽  
Author(s):  
Fernando Gómez ◽  
Luis F. Artigas
Keyword(s):  
Coastal Waters ◽  
English Channel ◽  
North East ◽  
The North ◽  
Benthic Dinoflagellates ◽  
The Pacific ◽  
The Pacific Ocean ◽  
Sandy Sediments ◽  
First Time ◽  
High Diversity

Benthic dinoflagellates collected in spring–summer 2010 and 2011 from intertidal sandy sediments of the shore of Wimereux (north-east English Channel, France) were examined by light microscopy, and some of them by scanning electron microscopy. High dinoflagellate species richness, 70 species, was evidenced when compared to the plankton observed in the coastal waters of the north-east English Channel. The greatest difficulty in performing accurate species identification mainly concerned the heterotrophic species of Amphidinium sensu lato, the laterally flattened species of Amphidiniopsis, as well as some heterotrophic species of Thecadinium. Several undescribed species are here illustrated, mainly within these genera. The differences in size between species of Herdmania and Sabulodinium suggest the occurrence of at least a second species for these monotypic genera. The species Amphidiniopsis hexagona, A. rotundata, A. uroensis and Sinophysis minima are reported for the first time in the Atlantic Ocean and on European coasts. Although these species were only previously known from the Pacific Ocean, they should not necessarily be considered as newcomers or invasive species due to the scarce coverage of the previous studies on sand-dwelling dinoflagellates.

ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF

2017 ◽  
Author(s):  
Svetlana Rubtsova ◽  
Svetlana Rubtsova ◽  
Natalya Lyamina ◽  
Natalya Lyamina ◽  
Aleksey Lyamin ◽  
...  
Keyword(s):  
Black Sea ◽  
Field Intensity ◽  
Deep Water ◽  
Coastal Waters ◽  
Integrated Management ◽  
Abiotic Factors ◽  
Environmental Safety ◽  
The Black Sea ◽  
Intensity Increase ◽  
First Time

The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.

scholarly journals Host density predicts the probability of parasitism by avian brood parasites

2019 ◽  
Vol 374 (1769) ◽  
pp. 20180204 ◽  
Author(s):  
Iliana Medina ◽  
Naomi E. Langmore
Keyword(s):  
Spatial Distribution ◽  
Reproductive Success ◽  
Host Species ◽  
Field Data ◽  
Host Density ◽  
Brood Parasites ◽  
Parasitism Rates ◽  
Analyse Data ◽  
First Time ◽  
Determining Factor

The spatial distribution of hosts can be a determining factor in the reproductive success of parasites. Highly aggregated hosts may offer more opportunities for reproduction but can have better defences than isolated hosts. Here we connect macro- and micro-evolutionary processes to understand the link between host density and parasitism, using avian brood parasites as a model system. We analyse data across more than 200 host species using phylogenetic comparative analyses and quantify parasitism rate and host reproductive success in relation to spatial distribution using field data collected on one host species over 6 years. Our comparative analysis reveals that hosts occurring at intermediate densities are more likely to be parasitized than colonial or widely dispersed hosts. Correspondingly, our intraspecific field data show that individuals living at moderate densities experience higher parasitism rates than individuals at either low or high densities. Moreover, we show for the first time that the effect of host density on host reproductive success varies according to the intensity of parasitism; hosts have greater reproductive success when living at high densities if parasitism rates are high, but fare better at low densities when parasitism rates are low. We provide the first evidence of the trade-off between host density and parasitism at both macro- and micro-evolutionary scales in brood parasites. This article is part of the theme issue ‘The coevolutionary biology of brood parasitism: from mechanism to pattern’.

Temperature, Salinity and Plankton in the Eastern North Atlantic and Coastal Waters of Britain, 1957.: I. The Characterisation and Distribution of Surface Waters

1963 ◽  
Vol 20 (3) ◽  
pp. 789-826 ◽  
Author(s):  
B. McK. Bary
Keyword(s):  
North Sea ◽  
North Atlantic ◽  
Coastal Waters ◽  
Water Bodies ◽  
English Channel ◽  
Oceanic Water ◽  
Climatic Fluctuations ◽  
The North ◽  
The North Sea ◽  
Eastern North Atlantic

Monthly temperature-salinity diagrams for 1957 have demonstrated that three surface oceanic "water bodies" were consistently present in the eastern North Atlantic; two are regarded as modified North Atlantic Central water which give rise to the third by mixing. As well in the oceanic areas, large and small, high or low salinity patches of water were common. Effects of seasonal climatic fluctuations differed in the several oceanic water bodies. In coastal waters, differences in properties and in seasonal and annual cycles of the properties distinguish the waters from the North Sea, English Channel and the western entrance to the Channel.The geographic distributions of the oceanic waters are consistent with "northern" and "southern" water bodies mixing to form a "transitional" water. Within this distribution there are short-term changes in boundaries and long-term (seasonal) changes in size of the water bodies.Water in the western approaches to the English Channel appeared to be influenced chiefly by the mixed, oceanic transitional water; oceanic influences in the North Sea appear to have been from northern and transitional waters.

Superovulation Influences Methylation Reprogramming and Delays Onset of DNA Replication in Both Pronuclei of Mouse Zygotes

2018 ◽  
Vol 156 (2) ◽  
pp. 95-105 ◽  
Author(s):  
Elif Diken ◽  
Matthias Linke ◽  
Jan Baumgart ◽  
Leonid Eshkind ◽  
Dennis Strand ◽  
...  
Keyword(s):  
Dna Replication ◽  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Mouse Embryos ◽  
Negative Effect ◽  
Independent Replication ◽  
Mouse Zygotes ◽  
Pn Stage ◽  
Significant Expression ◽  
First Time

Although an essential component of assisted reproductive technologies, ovarian stimulation, or superovulation, may interfere with the epigenetic reprogramming machinery during early embryogenesis and gametogenesis. To investigate the possible impact of superovulation particularly on the methylation reprogramming process directly after fertilization, we performed immunofluorescence staining of pronuclear (PN) stage embryos with antibodies against 5mC and 5hmC. PN stage embryos obtained by superovulation displayed an increased incidence of abnormal methylation and hydroxymethylation patterns in both maternal and paternal pronuclear DNA. Subsequent single-cell RT-qPCR analyses of the Tet1, Tet2, and Tet3 genes revealed no significant expression differences between PN stage embryos from spontaneously and superovulated matings that could be causative for the abnormal methylation and hydroxymethylation patterns. To analyze the possible contribution of TET-independent replication-associated demethylation mechanisms, we then determined the 5mC and 5hmC levels of PN stage mouse embryos using immunofluorescence analyses after inhibition of DNA replication with aphidicolin. Inhibition of DNA replication had no effect on abnormal methylation and hydroxymethylation patterns that still persisted in the superovulated group. Interestingly, the onset of DNA replication, which was also analyzed in these experiments, was remarkably delayed in the superovulated group. Our findings imply an impact of superovulation on both replication-dependent and -independent or yet unknown demethylation mechanisms in PN stage mouse embryos. In addition, they reveal for the first time a negative effect of superovulation on the initiation of DNA replication in PN stage mouse embryos.

Sign in / Sign up

Export Citation Format

Share Document