Seasonal cycles of activity and inactivity in some hydroids from Virginia and South Carolina, U.S.A.

1990 ◽  
Vol 68 (3) ◽  
pp. 442-450 ◽  
Author(s):  
Dale R. Calder
Keyword(s):  
South Carolina ◽  
Water Temperature ◽  
Cold Water ◽  
Warm Water ◽  
Late Winter ◽  
Tissue Water ◽  
Warm Water Species ◽  
Temperature Regimes ◽  
Water Species ◽  
Cold Water Species

Hydroids investigated in estuaries of Virginia and South Carolina, USA, were characteristically seasonal in occurrence. Of 20 species studied in Virginia, 14 were active only during warmer months and 6 only during colder months of the year. Seven of the 18 species examined in South Carolina were active all year, whereas 9 were active only in warmer months and 2 only during colder months. Reflecting the differing temperature regimes of the two study areas, warm-water species were active for a longer period of time in South Carolina than in Virginia; cold-water species were active longer in Virginia than in South Carolina. Warm-water species commenced activity in late winter or spring at higher temperatures than those coinciding with hydranth regression in autumn or early winter. Activity in cold-water species began at lower temperatures than those observed at regression in spring. Correlations were apparent in the seasonality, water temperature tolerances, and latitudinal distribution of most species. Field observations and laboratory experiments demonstrated that a number of species survived unfavourable periods as dormant coenosarc in stems and stolons. With the return of favourable conditions, new growth began and hydranths were regenerated from dormant tissue. Water temperature is considered the prime factor influencing the seasonal activity–inactivity cycles of hydroids in the two study areas.

Euphausiid invasion/dispersal in gulf stream cold-core rings

1983 ◽  
Vol 34 (4) ◽  
pp. 625 ◽  
Author(s):  
PH Wiebe ◽  
GR Flierl
Keyword(s):  
Gulf Stream ◽  
Cold Water ◽  
Warm Water ◽  
Dispersal Patterns ◽  
Near Surface ◽  
Warm Water Species ◽  
Living Species ◽  
Varied Response ◽  
Cold Core ◽  
Water Species

Invasion/dispersal patterns in the distribution and abundance of euphausiid species in four 2-8-month- old cold-core rings from the Gulf Stream suggest that several different physical exchange mechanisms are operating. The most important of these appear to be horizontal mixing in the mixed layer and exchange due to movement into or out of the trapped region at depth. A zone of minimum exchange is evident between 150 and 400 m. Changes in vertical distribution and abundance of warm-water species invading the ring environs suggest that only a few species, such as Stylocheiron carinatum, are able to penetrate and take advantage of the changing ring conditions in young- to middle-aged rings (2-8 months). Other near-surface warm-water species penetrate at slower rates regardless of whether they are vertical migrators (Euphausia brevis, E. hemigibba, E. tenera, Thysanopoda aequalis) or non-migrators (S. suhmii, S. abbreviatum). Deeper-living species such as S. afine, S. elongatum, Nematoscelis microps, and N. tenella, show minimal penetration of core waters in these four rings. Cold-water species expatriated in cold-core rings also show a varied response to ring decay, with some species disappearing rapidly-3-4 months (Thysanopoda longicaudata)-and others persisting for substantial periods-0.5-1 year (N. megalops, E. krohnii). Distribution of the latter two species indicates dispersal out beyond the ring core at the surface in the case of E. krohnii and at depths of 400-1 000 m in the case of N. megalops.

Cold-water species need warm water too

2021 ◽  
Vol 11 (4) ◽  
pp. 297-299
Author(s):  
Clint C. Muhlfeld
Keyword(s):  
Cold Water ◽  
Warm Water ◽  
Water Species ◽  
Cold Water Species

Cold‐water species deepen to escape warm water temperatures

2021 ◽  
Author(s):  
Shahar Chaikin ◽  
Shahar Dubiner ◽  
Jonathan Belmaker ◽  
Aaron MacNeil
Keyword(s):  
Cold Water ◽  
Warm Water ◽  
Water Species ◽  
Cold Water Species

scholarly journals EXPERIMENTAL ANALYSIS OF MODERN STATE OF REPRODUCTION FOR CHERRY SALMON ONCORHYNCHUS MASOU AT THE FISH FARMS OF SAKHALIN REGION

2019 ◽  
Vol 198 ◽  
pp. 195-208
Author(s):  
M. S. Myakishev ◽  
M. A. Ivanova ◽  
V. A. Kiselev ◽  
O. V. Zelennikov
Keyword(s):  
Water Temperature ◽  
Cold Water ◽  
Pink Salmon ◽  
Fish Farm ◽  
Warm Water ◽  
Fish Farms ◽  
Temperature Regimes ◽  
Water Fish ◽  
Growing Conditions ◽  
June July

Growing of cherry salmon juveniles under two different temperature regimes at the salmon farms Anivsky and Okhotsky in the fish-rearing cycle of 2016–2017 is analyzed. Data on cherry salmon growing for other fish farms of Sakhalin region collected in 1995–2017 are considered, as well. The periods of fish feeding and dynamics of their growth varied significantly in dependence on temperature conditions. The feeding started in April-May at the cold-water fish farms (Anivsky, Lesnoy, Sokolovsky, Urozhainiy) where the water temperature lowered in winter to 0.2–0.3 о С, but in February at Reidovo fish farm where the water temperature were not lower than 2 о С and in January at the most warm-water Okhotsky fish farm with the temperature never lower than 6.5 о С. In accordance with growing conditions, the growth rate of juveniles was high in winter month at the warm-water fish farms, where the ground water was used for rearing, but increased since May-June at the cold-water fish farms using natural heating of the river water. However, several cases were noted when the fish that accumulated less than 500–700 degree-days released from cold-water fish farms in June-July were larger than those from warm-water fish farms. Thus, cherry salmon is the only species among pacific salmons whose juveniles can be successfully grown at any temperature regime and consequently at any fish farm. This ability is reasoned by earlier spawning (along with pink salmon) and long period of development in rivers. At cold-water fish farms, the best results for cherry salmon growing could be achieved with the eggs planting in late August-September, whereas the time of eggs planting is not significant for warm-water fish farms.

scholarly journals Salinity effects on cultured Neogloboquadrina pachyderma (sinistral) from high latitudes: new paleoenvironmental insights

2021 ◽  
Vol 41 (1) ◽  
Author(s):  
Jacqueline Bertlich ◽  
Nikolaus Gussone ◽  
Jasper Berndt ◽  
Heinrich F. Arlinghaus ◽  
Gerhard S. Dieckmann
Keyword(s):  
Sea Ice ◽  
Cold Water ◽  
Weddell Sea ◽  
Wall Thickening ◽  
High Latitudes ◽  
Neogloboquadrina Pachyderma ◽  
Antarctic Sea Ice ◽  
The Antarctic ◽  
Water Species ◽  
Cold Water Species

AbstractThis study presents culture experiments of the cold water species Neogloboquadrina pachyderma (sinistral) and provides new insights into the incorporation of elements in foraminiferal calcite of common and newly established proxies for paleoenvironmental applications (shell Mg/Ca, Sr/Ca and Na/Ca). Specimens were collected from sea ice during the austral winter in the Antarctic Weddell Sea and subsequently cultured at different salinities and a constant temperature. Incorporation of the fluorescent dye calcein showed new chamber formation in the culture at salinities of 30, 31, and 69. Cultured foraminifers at salinities of 46 to 83 only revealed chamber wall thickening, indicated by the fluorescence of the whole shell. Signs of reproduction and the associated gametogenic calcite were not observed in any of the culture experiments. Trace element analyses were performed using an electron microprobe, which revealed increased shell Mg/Ca, Sr/Ca, and Na/Ca values at higher salinities, with Mg/Ca showing the lowest sensitivity to salinity changes. This study enhances the knowledge about unusually high element concentrations in foraminifera shells from high latitudes. Neogloboquadrina pachyderma appears to be able to calcify in the Antarctic sea ice within brine channels, which have low temperatures and exceptionally high salinities due to ongoing sea ice formation.

Estimating optimal salinity and temperature of chaetognaths

2012 ◽  
Vol 92 (6) ◽  
pp. 1399-1407 ◽  
Author(s):  
Dong Zhang ◽  
Zhao-Li Xu
Keyword(s):  
Survey Data ◽  
East China Sea ◽  
Marine Organisms ◽  
Warm Water ◽  
East China ◽  
Optimal Temperature ◽  
The East China Sea ◽  
Warm Water Species ◽  
China Sea ◽  
Water Species

Determining optimal temperature and salinity for marine organisms is a challenge for marine ecologists because not every species can be easily maintained in the laboratory for testing the influence of environmental parameters. To find a simple method to estimate the optimal temperature and salinity for marine organisms based on survey data, a reciprocal quadratic yield-density model was used for determining the optimal temperature or salinity from abundance data for six pelagic Chaetognatha species. The data for the modelling were collected in four surveys in the East China Sea (23°30′–33°N 118°30′–128°E) from 1997 to 2000. According to both survey data and results from the models, we analysed qualitatively and quantitatively the ecological characteristics of those species. Estimated optimal temperatures and salinities are 17.3°C and 14.1‰ for Sagitta nagae, 20.3°C and 13.8‰ for S. bedoti, 24.9°C and 32.9‰ for S. enflata, 22.5°C and 16.5‰ for S. ferox, 24.5°C and 34.1‰ for S. pacifica and 17.3°C and 14.1‰ for S. pulchra, respectively. Three ecological groups were evident in the East China Sea: the neritic, warm temperate water species (S. nagae); the neritic, warm water species (S. pulchra, S. ferox and S. bedoti); and the oceanic, warm water species (S. enflata and S. pacifica). Our results validate that the model is applicable for describing the relationship between chaetognaths abundance and temperature or salinity.

scholarly journals Oxythermal habitat as a primary driver of ecological niche and genetic diversity in cisco (Coregonus artedi)

2021 ◽  
Author(s):  
Ryan C Grow ◽  
Kyle D Zimmer ◽  
Jennifer L Cruise ◽  
Simon K Emms ◽  
Loren M Miller ◽  
...  
Keyword(s):  
Climate Change ◽  
Genetic Diversity ◽  
Dissolved Oxygen ◽  
Cold Water ◽  
Global Scale ◽  
Isotopic Niche ◽  
Coregonus Artedi ◽  
Primary Driver ◽  
Water Species ◽  
Cold Water Species

Cisco (Coregonus artedi) are threatened by climate change and lake eutrophication, and their oxythermal habitat can be assessed with TDO3, the water temperature at which dissolved oxygen equals 3 mg L-1. We assessed the influence of TDO3 on cisco habitat use, genetic diversity, diets, and isotopic niche in 32 lakes ranging from oligotrophic to eutrophic. Results showed that as TDO3 increased cisco were captured higher in the water column, in a narrower band, with higher minimum temperatures and lower minimum dissolved oxygen. TDO3 was also negatively related to cisco allelic richness and expected heterozygosity, likely driven by summer kill events. Moreover, TDO3 influenced the isotopic niche of cisco, as fish captured deeper were more depleted in δ13C and more enriched in δ15N compared to epilimnetic baselines. Lastly, cisco in high TDO3 lakes consumed more Daphnia, had fewer empty stomachs, and achieved larger body size. Our work identifies specific characteristics of cisco populations that respond to climate change and eutrophication effects, and provides a framework for understanding responses of other cold-water species at the global scale.

scholarly journals Lipidomic study of the influence of dietary fatty acids on structural lipids of cold-water nudibranch molluscs

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Andrey B. Imbs ◽  
Valeria P. Grigorchuk
Keyword(s):  
Fatty Acids ◽  
Molecular Species ◽  
Cold Water ◽  
High Resolution Mass Spectrometry ◽  
Dietary Fatty Acids ◽  
Alkyl Groups ◽  
Chain Lengths ◽  
Trophic Markers ◽  
Water Species ◽  
Cold Water Species

AbstractNudibranch molluscs occur in marine ecosystems worldwide and prey on numerous invertebrate species. During feeding, dietary fatty acids (FAs) unusual for nudibranchs are transferred to their lipids. Normal biomembrane functions require stable composition of structural polar lipids (PL), but the pathways of dietary FA utilization to PL in nudibranchs still remain unknown. A combination of chromatography and tandem high-resolution mass spectrometry was used to determine total lipid, PL, FA, and PL molecular species composition of two cold-water species of Dendronotus, which then were compared with those of Tritonia tetraquetra. The use of FA trophic markers showed that Dendronotus sp. and T. tetraquetra prey on different soft corals, while D. robustus may consumes hydrocorals and bryozoans. Nudibranch FA profiles were strongly modified by dietary FAs but their PL profilers were similar. Dietary FAs are not included in ceramide aminoethylphosphonate and inositol glycerophospholipids, but directed to ethanolamine, choline, and serine glycerophospholipids and, in some cases, form isobaric molecular species with different FA chain lengths. For such isobaric species, nudibranchs reduce the length of alkyl groups when very-long-chain FAs are obtained with diet. This molecular mechanism may explain the adaptation of nudibranch membrane structure to dietary input of unusual FAs.

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