A Possible Relict Population of Mesodesma deauratum (Turton):Bivalvia (Mesodesmatidae) from the Southeast Shoal, Grand Banks of Newfoundland

Extremely dense, localized concentrations of Turton's wedge clam Mesodesma deauratum (Turton) were found in quantitative grab samples on poorly sorted, medium to fine, low organic content sands (total organic carbon < 0.05%) at depths of 44–51 m at a single location on eastern Southeast Shoal of the Grand Banks of Newfoundland. Mean densities ranged from 24 to 5890 individuals∙m−2 and wet weight standing crop from 0 to 21.4 kg∙m−2. A peak standing crop of 69.4 kg∙m−2 was observed in one grab. There was a strong bimodal size distribution (17–27 and 34–56 mm shell length) at the site, but the two size groups never occurred together. Based on external growth checks, the smaller individuals were 4–5 yr old and the larger ones 10 to more than 15 yr. This population is suggested to be a relict of shallow littoral populations which probably existed in the area in the late Wisconsinan glacial period.

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Caloric Content of the Standing Crop of Benthic and Epibenthic Invertebrates of St. Margaret's Bay, Nova Scotia

Journal of the Fisheries Research Board of Canada ◽

10.1139/f68-166 ◽

1968 ◽

Vol 25 (9) ◽

pp. 1803-1811 ◽

Cited By ~ 40

Author(s):

V. M. Brawn ◽

D. L. Peer ◽

R. J. Bentley

Keyword(s):

Nova Scotia ◽

Standing Crop ◽

Caloric Content ◽

Wet Weight ◽

The Common ◽

The Mean ◽

Epibenthic Invertebrates

The benthos of St. Margaret's Bay at depths of 28–62 m was sampled quantitatively during the summer and the caloric contents of the common invertebrates determined. The shrimps, amphipods, and the polychaete Lumbrinereis with caloric contents between 1000 and 1300 cal/g wet weight had the highest caloric content of those tested. The mean caloric content of the standing crop was 76 kcal/m2 with the highest values occurring where the sand and silt–clay fractions of the sediment were nearly equal and the lowest where either sand or silt–clay predominated. Annelids and echinoderms together accounted for more than three-quarters of the caloric content of the standing crop.

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Estimating above- and below-ground macrophyte production in Scirpus tidal marshes

Canadian Journal of Botany ◽

10.1139/b88-059 ◽

1988 ◽

Vol 66 (2) ◽

pp. 368-374 ◽

Cited By ~ 11

Author(s):

Jean-François Giroux ◽

Jean Bédard

Keyword(s):

Standing Crop ◽

Belowground Biomass ◽

Tidal Marshes ◽

Optimal Size ◽

Lawrence Estuary ◽

Plant Parts ◽

Peak Standing Crop ◽

Below Ground ◽

The Difference ◽

St Lawrence Estuary

Different methods to estimate primary production of Scirpus marshes of the St. Lawrence estuary were compared. Quadrats 25 × 25 cm and cores 10 cm in diameter were found to be the optimal size to sample above- and below-ground standing crops, respectively. Ash content for different plant parts of various species was measured to obtain more accurate estimates of organic matter. A series of allometric equations relating stem height and mass were developed to estimate aerial standing crop from permanent nondestructively sampled plots. This method, however, overestimated standing crop compared with the destructive (harvest) method. The relationship between the above- and below-ground standing crop was also determined for the dominant species and used to predict belowground biomass without destructive sampling. Finally, the Smalley method provided the best estimates of net annual above- and below-ground production when losses attributed to decomposition were not considered. For less intensive studies, however, the methods based on peak standing crop and on the difference between maximum and minimum biomass would yield good approximations of above- and below-ground production.

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Estimation of Productivity and the Construction of Energy Budgets

Southwood's Ecological Methods ◽

10.1093/oso/9780198862277.003.0014 ◽

2021 ◽

pp. 430-457

Author(s):

Peter A. Henderson

Keyword(s):

Energy Density ◽

Standing Crop ◽

Energy Content ◽

Potassium Dichromate ◽

Dry Weight ◽

Energy Budgets ◽

Bomb Calorimetry ◽

Wet Weight ◽

Living Material ◽

Crop Energy

Methods to assess the size of a population and the interactions between populations in terms of biomass (weight of living material) or energy content are described. Biomass can be expressed as wet weight, dry weight (DW), shell-free dry weight (SFDW), ash-free dry weight, or as the amount of organic carbon present. The energy content of a material may be determined directly by oxidation, either by potassium dichromate in sulphuric acid, or by burning in oxygen and determining the amount of heat liberated. The latter method—bomb calorimetry—is most convenient and is widely used in ecology, but it involves drying the material, and volatile substances can be lost. Methods to estimate standing-crop, energy density, feeding and assimilation, and production are reviewed. Energy budgets can usefully be summarized and compared if the efficiencies of various processes are calculated. Dynamic energy budget models are introduced.

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Quantitative differences in the fauna of boreal mud associations

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400016180 ◽

1961 ◽

Vol 41 (3) ◽

pp. 599-616 ◽

Cited By ~ 53

Author(s):

A. D. McIntyre

Keyword(s):

Standing Crop ◽

Coarse Silt ◽

Important Species ◽

Factors Affecting ◽

Benthic Production ◽

Environmental Features ◽

Wet Weight ◽

Characteristic Species ◽

Similar Area ◽

Northern North Sea

SUMMARYThe fauna of a muddy area in the northern North Sea (the Fladen ground) is compared with that of a similar area in a Scottish west-coast sea loch (Loch Nevis). These areas were selected because certain similarities in environmental features and in fauna, coupled with their marked difference in biomass, make them particularly suitable for studies of the factors affecting benthic production.For macrobenthos samples (from a grab) a coarse sieve with round holes of 1-3 mm diameter and a fine sieve with meshes of 0-5 mm side were used. Meiobenthos samples (from a corer) were sieved through a 0124 mm mesh and the total residue stained in rose bengal.The Fladen ground, depth 140 m, had annual bottom temperatures between 6-31 and 8-22 C and salinities between 35-20 and 35-2.50. The deposit was mainly of coarse silt with abundant tests of small Foraminifera. The fauna is redescribed. The characteristic species was the foraminifer Saccammina sphaerica. By separating empty tests from living specimens it is shown that this species was not so abundant as had been thought. The main lamellibranch was Thyasira equalis, not T. flexuosa as recorded in previous work. Other important species were the polychaetes Paraonis gracilis, Myriochele heeri, Spiophanes kroyeri, Tharyx sp., Lumbrineris impatiens, and Nephthys incisa. The standing crop of macrobenthos was 6-42 g/m2 wet weight.

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Measurements of Benthic Macroinvertebrate Standing Crop from the Canadian Continental Shelf and Slope of Southern Davis Strait and Ungava Bay

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f83-087 ◽

1983 ◽

Vol 40 (5) ◽

pp. 652-657 ◽

Cited By ~ 6

Author(s):

Patrick L. Stewart

Keyword(s):

Continental Shelf ◽

North American ◽

Standing Crop ◽

Benthic Macroinvertebrate ◽

Baffin Island ◽

Medium Sand ◽

Grand Banks ◽

Sediment Content ◽

Davis Strait

Benthic macroinvertebrate standing crop at 14 stations on the Canadian continental shelf, southeast of Baffin Island, ranged from 19.8 to 479.9 g/m2 and was about the same size for given depths, as reported for the Grand Banks of Newfoundland, and higher than reported in more southerly portions of the eastern North American continental shelf. Standing crop was correlated negatively with depth and sediment content of both fine and medium sand.

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Late Wisconsinan ice advances, ice extent, and glacial regimes interpreted from seismic data, sediment physical properties, and Foraminifera: Halibut Channel, Grand Banks of Newfoundland

Deglacial history and relative sea-level changes, northern New England and adjacent Canada ◽

10.1130/0-8137-2351-5.51 ◽

2001 ◽

Cited By ~ 2

Author(s):

Ann A. L. Miller ◽

Gordon B. J. Fader ◽

Kathryn Moran

Keyword(s):

Physical Properties ◽

Seismic Data ◽

Grand Banks ◽

Late Wisconsinan ◽

Sediment Physical Properties

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Trophic ecology of Patagonian flounder Paralichthys patagonicus (Jordan, 1889) in the Argentine-Uruguayan Coastal Ecosystem

Marine and Fishery Sciences (MAFIS) ◽

10.47193/mafis.3512022010109 ◽

2021 ◽

Vol 35 (1) ◽

Author(s):

Gonzalo H. Troccoli ◽

Andrés C. Milessi ◽

Noemí Marí ◽

Daniel Figueroa ◽

Agustín M. De Wysiecki

Keyword(s):

Food Habits ◽

Diet Composition ◽

Trophic Ecology ◽

Pelagic Fish ◽

Coastal Ecosystem ◽

Prey Category ◽

Important Prey ◽

Content Analyses ◽

Size Groups ◽

Wet Weight

Food habits and diet composition of Patagonian flounder Paralichthys patagonicus (Jordan, 1889) were studied on the basis of stomach content analyses from 828 specimens (512 females, 304 males, 12 unsexed) collected during 16 commercial cruises between February 2009 and April 2010 in the Argentine-Uruguayan Coastal Ecosystem (34° S-41° S). A total of 272 stomachs (32.9%) contained food (184 females and 84 males), among which 20 prey taxa were identified. The most important prey category was pelagic fish, primarily Argentine anchovy (Engraulis anchoita), followed by rough scad (Trachurus lathami). Evidence showed that females consumed a higher total wet weight of prey compared to males. Results also suggested a specialised diet over E. anchoita, across all sex and size groups. The estimated trophic level for the population of P. patagonicus was 4.16. This study suggests that P. patagonicus is a tertiary piscivorous consumer of the trophic food web in the region, and reveals changes in the prey consumption compared with previous studies.

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Initial Egg Weight, Time to Maximum Alevin Wet Weight, and Optimal Ponding Times for Chinook Salmon (Oncorhynchus tshawytscha)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f85-036 ◽

1985 ◽

Vol 42 (2) ◽

pp. 287-291 ◽

Cited By ~ 38

Author(s):

Peter J. Rombough

Keyword(s):

British Columbia ◽

Chinook Salmon ◽

Oncorhynchus Tshawytscha ◽

Incubation Temperature ◽

Egg Weight ◽

Size Groups ◽

Wet Weight ◽

Time Required ◽

Incubation Temperatures ◽

Best Fit

Eggs of chinook salmon (Oncorhynchus tshawytscha) were segregated into eight size groups (range 163–437 mg) and incubated at 5, 7.5, 10, and 12.5 °C. The time required to reach maximum alevin wet weight (MAWW) varied significantly (p < 0.01) both with mean incubation temperature (T °C) and with initial egg weight (W mg). A good (R2 = 98.4%, n = 21) prediction of days postfertilization to MAWW (D) is given by[Formula: see text]Optimal ponding times are closely associated with the attainment of MAWW and can be estimated using this equation. Data relating mean incubation temperatures (T) to actual ponding time were collected from 17 hatcheries throughout British Columbia. The equation[Formula: see text]where D′ is days postfertilization to ponding, provided the best fit to the data (R2 = 97.5%, n = 85). Hatchery ponding times were not significantly different from times to MAWW predicted for 200-mg eggs.

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