Fourier Analysis of Sea Scallop (Placopecten magellanicus) Shells in Determining Population Structure

1994 ◽  
Vol 51 (2) ◽  
pp. 348-356 ◽  
Author(s):  
E. L. Kenchington ◽  
W. E. Full
Keyword(s):  
Shell Shape ◽  
Bay Of Fundy ◽  
Shape Descriptors ◽  
Placopecten Magellanicus ◽  
Harmonic Numbers ◽  
Sea Scallop ◽  
Species Comparisons ◽  
Sea Scallops ◽  
Post Hoc ◽  
Fourier Harmonics

Sea scallops (Placopecten magellanicus) were sampled from each of four scallop beds: the northeast peak of Georges Bank, Western Bank, St. Pierre Bank, and the Bay of Fundy near Digby, N.S. The outlines of scallop top shells were captured by video imagery using a semiautomated approach. Fourier shape descriptors were calculated and analyzed. Age and year-class effects were shown to be important factors influencing scallop shell shape. Allometric effects on Fourier harmonics also have a significant influence on shell shape in this species. Comparisons of Fourier harmonics between scallop beds separated by age and sampling year, and corrected for allometry, revealed significant differences in the majority of harmonic numbers. Post hoc analyses identified St. Pierre Bank and the Bay of Fundy as being significantly different from the other beds in a suite of separate analyses.

Paralytic Shellfish Poison in Sea Scallops (Placopecten magellanicus) in the West Atlantic

1983 ◽  
Vol 40 (3) ◽  
pp. 313-318 ◽  
Author(s):  
G. S. Jamieson ◽  
R. A. Chandler
Keyword(s):  
Adductor Muscle ◽  
Bay Of Fundy ◽  
Georges Bank ◽  
Placopecten Magellanicus ◽  
Eastern Canada ◽  
The West ◽  
Monthly Basis ◽  
Sea Scallop ◽  
Paralytic Shellfish ◽  
Sea Scallops

Levels of Gonyaulax excavata toxin in sea scallop (Placopecten magellanicus) tissues were monitored in eastern Canada on a monthly basis between 1977 and 1981. All tissues but the adductor muscle were found to be highly toxic in Bay of Fundy scallops, with negligible toxicity observed in scallops from Georges Bank, the outer Scotian Shelf, and Northumberland Strait scallops. Level of Bay of Fundy toxicity was much higher than previously observed (maximum digestive gland toxicity: 150 000 μg/100 g in March 1978), and recent average monthly toxicity for Bay of Fundy scallop roe ranged from 184 to 286 μg/100 g. Considerable fluctuation in toxicity can occur between adjacent months, and peak toxicities in sea scallops occur during fail and winter months. Scallop roe fisheries should be permitted to be established for scallops fished from the northern part of Georges Bank and Northumberland Strait. However, a closed zone for scallop roe should be established in the Bay of Fundy and adjacent Scotian Shelf.Key words: scallop, PSP, Gonyaulax, Placopecten, mollusk

Identification of Planktonic Sea Scallop Larvae (Placopecten magellanicus) (Gmelin)

1987 ◽  
Vol 44 (7) ◽  
pp. 1361-1366 ◽  
Author(s):  
M. J. Tremblay ◽  
L. D. Meade ◽  
G. V. Hurley
Keyword(s):  
Bay Of Fundy ◽  
Placopecten Magellanicus ◽  
Sea Scallop ◽  
Bivalve Larvae ◽  
Scallop Larvae ◽  
Shape And Size

Methods for the collection, processing, and identification of planktonic sea scallop larvae (Placopecten magellanicus) (Gmelin) are described. Bivalve larvae collected from the Bay of Fundy were compared with cultured P. magellanicus larvae. Sea scallop larvae collected from the plankton can be tentatively identified based on shape and size; examination of the larval hinge structure allows confirmation.

scholarly journals An Econometric Analysis of Atlantic Sea Scallop Markets

1978 ◽  
Vol 7 (2) ◽  
pp. 111-118
Author(s):  
David A. Storey ◽  
Cleve E. Willis
Keyword(s):  
United States ◽  
New England ◽  
Econometric Analysis ◽  
Placopecten Magellanicus ◽  
Northeastern United States ◽  
Quarter Century ◽  
Sea Scallop ◽  
Sea Scallops ◽  
Fish And Shellfish

The Atlantic sea scallop (Placopecten magellanicus) is harvested in the waters off the coast of the northeastern United States and Canada by vessels from both countries. The Atlantic sea scallop fishery has been an important fishery in the Northeastern U.S. in recent decades. This is particularly true for New England where, during the quarter-century ending in 1976, over 10 percent of the value of all fish and shellfish landed was attributable to the harvest of sea scallops.

scholarly journals Shell growth of sea scallops (Placopecten magellanicus) in the southern and northern Great South Channel, USA

2006 ◽  
Vol 63 (5) ◽  
pp. 811-821 ◽  
Author(s):  
Bradley P. Harris ◽  
Kevin D.E. Stokesbury
Keyword(s):  
Shell Growth ◽  
Shell Height ◽  
Management Strategies ◽  
Height Distribution ◽  
Placopecten Magellanicus ◽  
Geographic Scale ◽  
Sea Scallop ◽  
Asymptotic Size ◽  
The Usa ◽  
Sea Scallops

Abstract Shell growth of sea scallops in two commercially productive regions of the Great South Channel (GSC) (41°4′N 69°16′W) was studied using tag–recapture experiments. Commercial fishers captured and returned 9.7% of the 11 704 sea scallops tagged in the southern GSC study area, and 7.9% of the 18 274 sea scallops tagged in the northern GSC study area. Scallop density and shell height distribution were sampled with underwater video in the two study areas. In the southern GSC tagged scallops grew faster, reached larger asymptotic size, and had higher growth performance (Φ′) than in the northern GSC study area. Mean sea scallop density in the southern GSC was 0.117 scallops m−2 (s.e. = 0.01), and 2.601 scallops m−2 (s.e. = 0.28) in the northern GSC. Environmental factors, fishing pressure, and sea scallop density all influence shell growth on a fine geographic scale (1–100 km2) and should be considered in area-specific management strategies, such as that currently used in the USA sea scallop fishery.

Accumulation of domoic acid by the sea scallop (Placopecten magellanicus) fed cultured cells of toxic Pseudo-nitzschia multiseries

1997 ◽  
Vol 54 (4) ◽  
pp. 907-913 ◽  
Author(s):  
D J Douglas ◽  
E R Kenchington ◽  
C J Bird ◽  
R Pocklington ◽  
B Bradford ◽  
...  
Keyword(s):  
Digestive Gland ◽  
Domoic Acid ◽  
Cultured Cells ◽  
Exposure Period ◽  
Adductor Muscle ◽  
Placopecten Magellanicus ◽  
Bivalve Molluscs ◽  
Destructive Sampling ◽  
Sea Scallop ◽  
Sea Scallops

Sea scallops (Placopecten magellanicus) were fed Pseudo-nitzschia multiseries (formerly P. pungens f. multiseries, Nitzschia pungens f. multiseries) cells of high domoic acid (DA) content (4.0-6.7 pg DA cdot cell-1) for 22 days, followed by 14 days of feeding with nontoxic microalgae. DA was incorporated within 24 h by the scallops, with increased uptake after 6 days, and was concentrated in tissues in the following order: digestive gland >> remaining soft tissue >> adductor muscle. A maximum DA concentration of 3108 mu g cdot g-1 was recorded in the digestive gland, approximately 150 times the regulatory limit (20 mu g DA cdot g-1) and among the highest levels observed in bivalve molluscs; however, only trace amounts, 0.7-1.5 mu g cdot g-1, were found concomitantly in the adductor muscle. At the end of the exposure period, 50.9% of the DA that had been supplied to the scallops had been incorporated into the tissues. Concentrations in the digestive gland 14 days after termination of the toxic diet remained high, 752 mu g DA cdot g-1. Throughout the experiment, there was no sign of illness or mortality attributable to high DA loading, although the destructive sampling of animals did not allow us to assess the effects of the toxin in the longer term.

Paralytic Shellfish Toxins in the Sea Scallop, Placopecten magellanicus, in the Bay of Fundy

1979 ◽  
Vol 36 (1) ◽  
pp. 32-36 ◽  
Author(s):  
C. P. Hsu ◽  
A. Marchand ◽  
Y. Shimizu ◽  
G. G. Sims
Keyword(s):  
Key Words ◽  
Bay Of Fundy ◽  
Placopecten Magellanicus ◽  
Toxic Dinoflagellate ◽  
Paralytic Shellfish Poison ◽  
Shellfish Toxins ◽  
Sea Scallop ◽  
Paralytic Shellfish Toxins ◽  
Paralytic Shellfish ◽  
A Minor

The paralytic shellfish poison of the giant sea scallop, Placopecten magellanicus (Gmelin), from the Bay of Fundy has been analyzed. Of eight toxins isolated, seven were identified with those previously recognized in various sources including the Atlantic toxic dinoflagellate, Gonyaulax tamarensis cells. The major components were gonyautoxin-I, gonyautoxin-II, and neosaxitoxin; saxitoxin was responsible for only a very small portion of the total toxicity. A minor toxin that was eluted between neosaxitoxin and saxitoxin in the chromatography system was found to be new and designated as gonyautoxin-VII. Key words: paralytic shellfish poisons, gonyautoxins, neosaxitoxin, Gonyaulax tamarensis

Paralytic Shellfish Poison in Sea Scallops (Placopecten magellanicus, Gmelin)

1965 ◽  
Vol 22 (5) ◽  
pp. 1137-1149 ◽  
Author(s):  
N. Bourne
Keyword(s):  
Atlantic Coast ◽  
Bay Of Fundy ◽  
Georges Bank ◽  
Placopecten Magellanicus ◽  
Paralytic Shellfish Poison ◽  
Paralytic Shellfish ◽  
Adductor Muscles ◽  
Sea Scallops

Bioassays for paralytic shellfish poison were carried out in sea scallops (Placopecten magellanicus, Gmelin) from the major scallop producing areas off the Canadian Atlantic coast. There was very little or no toxin in Georges Bank or southern Gulf of St. Lawrence scallops. In Bay of Fundy scallops, adductor muscles and gills were poison-free but livers and mantles remained toxic the year round. The highest score of roes in these scallops was 43 μg of toxin per 100 g of roe.

Estimation of the capture efficiency and abundance of Atlantic sea scallops (Placopecten magellanicus) from paired photographic–dredge tows using hierarchical models

2019 ◽  
Vol 76 (6) ◽  
pp. 847-855 ◽  
Author(s):  
Timothy J. Miller ◽  
Deborah R. Hart ◽  
Karen Hopkins ◽  
Norman H. Vine ◽  
Richard Taylor ◽  
...  
Keyword(s):  
Hierarchical Models ◽  
Information Criterion ◽  
Placopecten Magellanicus ◽  
Camera System ◽  
Multiple Images ◽  
Sea Scallop ◽  
Multiple Observations ◽  
Abundance Estimates ◽  
Stock Assessments ◽  
Sea Scallops

The efficiency of survey gear is an important measure that can be used to estimate the absolute scale of populations in assessment models. We develop a general hierarchical model for estimating the efficiency of a New Bedford-style sea scallop (Placopecten magellanicus) survey dredge from paired dredge and Habcam camera system tows. Habcam data for each tow consist of multiple images that give information on within-tow variability of scallop density. The model accounts for these multiple observations as well as the possibility of differences between the true densities in dredge and Habcam pairs due to the pairs not covering exactly the same ground. We fit several models with alternative assumptions to observations on Atlantic sea scallops and compare the relative performance using Akaike’s information criterion. The best performing model estimated higher dredge efficiency on fine substrates than on coarse ones (approximately 0.40 and 0.27, respectively). Our results inform the scale of annual abundance estimates from dredge surveys and reduce uncertainty in the sea scallop stock assessments.

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