Effect of Turbidity on the Temporal and Spatial Utilization of the Inner Bay of Fundy by American Shad (Alosa sapidissima) (Pisces: Clupeidae) and its Relationship to Local Fisheries

1983 ◽  
Vol 40 (S1) ◽  
pp. s322-s330 ◽  
Author(s):  
M. J. Dadswell ◽  
G. D. Melvin ◽  
P. J. Williams
Keyword(s):  
Light Intensity ◽  
Atlantic Coast ◽  
American Shad ◽  
Bay Of Fundy ◽  
Eastern Canada ◽  
Alosa Sapidissima ◽  
Migration Timing ◽  
Swimming Depth ◽  
Preference Zone ◽  
High Turbidity

Since 1750, a unique, directed fishery for American shad (Alosa sapidissima) has existed in shallow, turbid, mega-tidal embayments of the inner Bay of Fundy during summer and fall. Tagging experiments indicated that migrating shad consisting of intermixed, river populations from the entire Atlantic coast of North America occur there between June and October. Shad migration was counterclockwise around the Bay following the residual current structure. Presence and duration of the shad run in Cumberland Basin was a result of interaction between migration timing, turbidity, and temperature. Mean daytime swimming depth was related to tidal phase and turbidity. High turbidity (Secchi [Formula: see text]) of the mega-tidal embayments apparently extends the preference zone for light intensity of ocean-feeding shad into surface waters (2–10 m), making them accessible to the local fishery.Key words: drift gillnets, shad migration, light intensity preference, swimming depth, mega-tidal, eastern Canada

Usefulness of Meristic and Morphometric Characters in Discriminating Populations of American Shad (Alosa sapidissima) (Ostreichthyes:Clupeidae) Inhabiting a Marine Environment

1992 ◽  
Vol 49 (2) ◽  
pp. 266-280 ◽  
Author(s):  
Gary D. Melvin ◽  
Michael J. Dadswell ◽  
Joseph A. McKenzie
Keyword(s):  
North Carolina ◽  
Atlantic Coast ◽  
American Shad ◽  
Cape Cod ◽  
Bay Of Fundy ◽  
Morphometric Characters ◽  
Alosa Sapidissima ◽  
Linear Discriminant ◽  
Percent Correct ◽  
Spawning Run

American shad (Alosa sapidissima) concentrate each summer in the basins of the inner Bay of Fundy during their coastal migration. Tag returns from 6124 marked shad indicated that these fish return to every important shad spawning stream on the Atlantic coast. Ten meristic and 16 morphometric characters of shad collected from 14 rivers (range: Florida to Quebec) were used to develop linear discriminant functions (LDF). Variables which differed significantly (p < 0.05) between the sexes, year of sampling, and the time of collection during the spawning run were removed prior to LDF classification. The highest mean percent correct classification was achieved by the allocation of fish into regional groups, after classification into individual rivers, using pooled meristic and morphometric variables: 87.2% for males and 82.4% for females. The functions were then used to assign shad from a mixed populations (Cumberland Basin) to individual rivers and regions. Of these, 10.9% were assigned to rivers south of Cape Lookout, North Carolina, 38.1% to rivers between Cape Lookout and Cape Cod, 32.5% into rivers of the Bay of Fundy, and 18.5% into rivers in the Gulf of St. Lawrence. In-river tag returns were compared with LDF classification and were found to be similar.

Parasites of American shad, Alosa sapidissima (Osteichthyes: Clupeidae), from rivers of the North American Atlantic coast and the Bay of Fundy, Canada

1993 ◽  
Vol 71 (5) ◽  
pp. 941-946 ◽  
Author(s):  
W. E. Hogans ◽  
Michael J. Dadswell ◽  
Leslie S. Uhazy ◽  
Ralph G. Appy
Keyword(s):  
Atlantic Coast ◽  
Geographic Location ◽  
Diversity Indices ◽  
American Shad ◽  
Bay Of Fundy ◽  
Alosa Sapidissima ◽  
The North ◽  
Abundance And Diversity ◽  
First Time ◽  
Hysterothylacium Aduncum

Parasites belonging to a total of 26 taxa were recovered from 695 American shad (Alosa sapidissima) sampled from six rivers and one marine location (Cumberland Basin, Bay of Fundy) on the east coast of North America. Of these, 23 taxa are reported from American shad for the first time. Species identified were predominantly boreal marine forms that have low host specificities and widespread distributions. Two species, Hysterothylacium aduncum and Scolex pleuronectis, were found in American shad from all localities (> 60% prevalence). Relative abundance and diversity indices of the parasite assemblages varied in relation to geographic location and temporally in Cumberland Basin. These data suggest that there is different timing of arrival and departure of shad from individual river populations in Cumberland Basin. High levels of prevalence and incidence of exotic, southern parasite species, such as Genitocotyle atlantica, in shad from Cumberland Basin and most or all river populations indicate that all individual shad spend some portion of their life at or near the southern extent of their reported range.

Discrimination among Atlantic Coast Populations of American Shad (Alosa sapidissima) Using Mitochondrial DNA

1991 ◽  
Vol 48 (9) ◽  
pp. 1724-1734 ◽  
Author(s):  
Kathleen Nolan ◽  
Joseph Grossfield ◽  
Isaac Wirgin
Keyword(s):  
Mitochondrial Dna ◽  
Atlantic Coast ◽  
Restriction Enzymes ◽  
Hudson River ◽  
Restriction Endonuclease Analysis ◽  
The United States ◽  
American Shad ◽  
Alosa Sapidissima ◽  
Coastal Fisheries ◽  
Latitudinal Clines

We used restriction endonuclease analysis of mitochondrial DNA (mtDNA) to differentiate among spawning stocks of American shad (Alosa sapidissima). Highly purified mtDNA was isolated from shad from four major spawning rivers: the St. John's (Florida), the Delaware, and the Hudson in the United States and the Miramichi in New Brunswick, Canada. Primarily four-and-five-base-cutting restriction enzymes were used to prepare both individual enzyme profiles and composite genotypes. Three separate spawning stocks, St. John's, Delaware–Hudson, and Miramichi, could be distinguished based on frequency differences in mtDNA genotypes generated by single restriction enzyme digests. We could not distinguish Delaware from Hudson River shad. Only a single definitive restriction site polymorphism was observed among all samples, but polyacrylamide gel electrophoretic mobility variants were common. Eco RI, Dde I, and Rsa I revealed stock-specific mtDNA genotypes. The frequencies of some genotypes occurred in latitudinal clines. Fifty-seven of 81 fish showed individual-specific composite genotypes. Geographic partitioning of genotypes suggests that mtDNA analysis may be useful for the identification of some American shad stocks and their relative contributions to mixed coastal fisheries.

Redescription of Clavellisa cordata Wilson, 1915 (Copepoda: Lernaeopodidae) from anadromous clupeids in eastern Canada

1987 ◽  
Vol 65 (6) ◽  
pp. 1559-1563 ◽  
Author(s):  
L. A. Rubec ◽  
W. E. Hogans
Keyword(s):  
Original Description ◽  
American Shad ◽  
Alosa Pseudoharengus ◽  
Eastern Canada ◽  
Closely Related Species ◽  
Alosa Sapidissima ◽  
Distinctive Features ◽  
Blueback Herring ◽  
Alosa Aestivalis ◽  
Northeastern Atlantic

The male and female of Clavellisa cordata Wilson, 1915 are described from the gills of blueback herring (Alosa aestivalis), alewife (Alosa pseudoharengus), and American shad (Alosa sapidissima) collected in New Brunswick. The female differs from the original description in the presence of uropods, the apical armature of the first antennae, second antennae, and first maxillae, the presence of secondary teeth on the mandibles, and several additional processes on the maxillipeds. The male differs in the presence of uropods and in the detailed morphology of the various appendages, in particular the maxillipeds. Distinctive features of Clavellisa spinosa, another species occurring in the northwestern Atlantic, are briefly discussed. Differences between Clavellisa cordata and a closely related species, Clavellisa emarginata, occurring in the northeastern Atlantic, are listed. The present redescription of Clavellisa cordata represents a northern range extension and three new Canadian host records.

Genetic Mixed-Stock Analysis of American Shad in Two Atlantic Coast Fisheries: Delaware Bay, USA, and Inner Bay of Fundy, Canada

2014 ◽  
Vol 34 (6) ◽  
pp. 1190-1198 ◽  
Author(s):  
John Waldman ◽  
Daniel Hasselman ◽  
Paul Bentzen ◽  
Michael Dadswell ◽  
Lorraine Maceda ◽  
...  
Keyword(s):  
Atlantic Coast ◽  
Delaware Bay ◽  
American Shad ◽  
Bay Of Fundy ◽  
Mixed Stock Analysis ◽  
Stock Analysis ◽  
Mixed Stock

Ocean Migration Rates of American Shad (Alosa sapidissima)

1977 ◽  
Vol 34 (9) ◽  
pp. 1422-1426 ◽  
Author(s):  
William C. Leggett
Keyword(s):  
Swimming Performance ◽  
Atlantic Coast ◽  
Similar Rate ◽  
American Shad ◽  
Individual Growth ◽  
Alosa Sapidissima ◽  
Migration Rates ◽  
Migratory Path ◽  
Temperature Preferences ◽  
Individual Growth Rate

Ocean migration rates of American shad (Alosa sapidissima), estimated from tag returns, averaged 21 km/day during the spring northward migration along the Atlantic coast between Chesapeake Bay and the Bay of Fundy and appear to be regulated by temperature preferences of the species. The fall southward migration is believed to occur at a similar rate. An evaluation of known saltwater swimming speeds and of prevailing currents along the migratory path indicates that the distance traveled during the northward and southward migrations may exceed the minimum distance route by up to 100 and 500%, respectively, and suggests that considerable nondirected movement may occur. The sustained swimming speeds of juvenile shad at the time of their entry into the sea are close to the estimated minimum sustained speeds required to complete the initial migration in the sea. Annual density-dependent variation in individual growth rate, through its influence on size at emigration and the resulting swimming performance of juveniles, may significantly influence juvenile survival. Key words: American shad, Alosa sapidissima, migration rates, swim speeds, survival

Fidelity of American Shad, Alosa sapidissima (Gupeidae), to its River of Previous Spawning

1986 ◽  
Vol 43 (3) ◽  
pp. 640-646 ◽  
Author(s):  
Gary D. Melvin ◽  
Michael J. Dadswell ◽  
James D. Martin
Keyword(s):  
Nova Scotia ◽  
Marine Environment ◽  
American Shad ◽  
Geographical Range ◽  
Bay Of Fundy ◽  
Alosa Sapidissima ◽  
St Lawrence River

Of 5074 adult American shad, Alosa spidissima, tagged in the Annapolis River, Nova Scotia, during the 1981 and 1982 spawning runs, 292 (5.8%) were recaptured, 180 in the river during the same year, 56 in the river in subsequent years, 53 at distant marine sites, and 1 in another Nova Scotia river. Recovery from 6124 adult shad tagged in a marine environment (Cumberland Basin, Bay of Fundy) was similar (395 recaptures, 6.5%) but distribution was markedly different. Thirty-five were taken in the Basin during the same year, but only 7 in subsequent years. Conversely, 139 were recaptured at distant marine sites, and 214 in rivers from the St. Lawrence River, Quebec, to the St. John's River, Florida. Assuming equal probabilities for recapture within this species' geographical range, Annapolis River freshwater recaptures were specific for the Annapolis River but Cumberland freshwater recaptures were nonspecific. Except for two returns, possible strays, fidelity to the Annapolis was 97%.

Marine tube-dwelling diatoms of eastern Canada: descriptions, checklist, and illustrated key

1984 ◽  
Vol 62 (4) ◽  
pp. 778-794 ◽  
Author(s):  
Christopher S. Lobban
Keyword(s):  
New Species ◽  
Northwest Territories ◽  
Common Species ◽  
Bay Of Fundy ◽  
Eastern Canada ◽  
Lawrence Estuary ◽  
The Common ◽  
Living Material ◽  
St Lawrence Estuary ◽  
A New Species

From a study of living materials and specimens in several regional herbaria, a list has been drawn up of all the common and several of the rarer tube-dwelling diatoms of eastern Canada. Descriptions, illustrations of living material and acid-cleaned valves, and a key to the species are provided. Most specimens were from the Atlantic Provinces and the St. Lawrence estuary, but a few were from the Northwest Territories. By far the most common species is Berkeleya rutilans. Other species occurring commonly in the Quoddy Region of the Bay of Fundy, and sporadically in space and time elsewhere, arc Navicula delognei (two forms), Nav. pseudocomoides, Nav. smithii, Haslea crucigera, and a new species, Nav.rusticensis. Navicula ramosissima and Nav. mollis in eastern Canada are usually found as scattered cohabitants in tubes of other species. Nitzschia tubicola and Nz. fontifuga also occur sporadically as cohabitants.

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