Helminth parasites of redfish (Sebastes fasciatus) from the Scotian Shelf, Bay of Fundy, and eastern Gulf of Maine

1988 ◽  
Vol 66 (3) ◽  
pp. 617-621 ◽  
Author(s):  
J. S. Scott
Keyword(s):  
Parasite Species ◽  
Gulf Of Maine ◽  
General Pattern ◽  
Bay Of Fundy ◽  
Fish Length ◽  
Helminth Parasites ◽  
Scotian Shelf ◽  
Species Numbers ◽  
Low Prevalence ◽  
Total Species

Examination of alimentary tracts of 319 redfish (Sebastes fasciatus) from the Scotian Shelf, Bay of Fundy, and eastern Gulf of Maine yielded 13 helminth species: 7 Digenea, 3 Cestoda, 2 Nematoda, and 1 Acanthocephala. Total species composition was virtually identical with that found in the redfish of the Labrador–Newfoundland area. Prevalence and intensity of infection were low and showed little variation with area or fish length except in the case of the nematodes Anisakidae for which low prevalence and intensity (3.9 and 1.0, respectively) in the eastern Gulf of Maine contrasted with higher values (39.1–71.4 and 1.7–7.7, respectively) in the remainder of the survey area. The general pattern of species numbers was low numbers (2–4) in the fish of the Gulf of Maine and southwest Nova Scotia, and higher numbers (8–13) in those of the central and northeast Scotian Shelf. Small- to intermediate-sized fish contained more species (7–12) than the largest fish (4). The combination of exceptionally low prevalence of Anisakidae and low parasite species numbers in redfish of the eastern Gulf of Maine area suggests that the stock there is distinct from those of the Scotian Shelf and Bay of Fundy.

Helminth parasites of the alimentary tract of the hakes (Merluccius, Urophycis, Phycis: Teleostei) of the Scotian Shelf

1987 ◽  
Vol 65 (2) ◽  
pp. 304-311 ◽  
Author(s):  
J. S. Scott
Keyword(s):  
Alimentary Tract ◽  
Parasite Species ◽  
Gulf Of Maine ◽  
Parasite Prevalence ◽  
Fish Length ◽  
Helminth Parasites ◽  
Scotian Shelf ◽  
High Prevalence ◽  
Merluccius Bilinearis ◽  
Separate Population

Alimentary tracts of the five common hakes of the Scotian shelf (Urophycis chuss, Urophycis tenuis, Phycis chesteri, Merluccius bilinearis, Merluccius albida) were examined for helminth parasites. A total of 29 species was found: 17 Digenea, 4 Cestoda, 6 Nematoda, 2 Acanthocephala. The greatest numbers of species were found in the closely associated U. tenuis (25) and U. chuss (19). Phycis chesteri hosted a moderate number (14) but included 3 digeneans that are typical of deep water (Anomalotrema koiae, Lethadena profunda, Paraccacladium jamiesoni) not found in the other hakes. The merlucciids were characterized by low numbers of parasite species, particularly of digeneans, but showed high prevalence of the host-specific cestode Clestobothrium crassiceps. The effects of geographic distribution, fish length, and depth of capture on parasite prevalence were examined for those parasites that were adequately represented. There was little difference in geographical distribution except in the case of C. crassiceps, in which distribution suggested a separate population of M. bilinearis on the Scotian Shelf from that of the Gulf of Maine. Fish length and depth of capture had little effect on parasite prevalence.

The distribution of right whales and Zooplankton in the Bay of Fundy, Canada

1989 ◽  
Vol 67 (6) ◽  
pp. 1411-1420 ◽  
Author(s):  
L. D. Murison ◽  
D. E. Gaskin
Keyword(s):  
Gulf Of Maine ◽  
Calanus Finmarchicus ◽  
Eubalaena Glacialis ◽  
Bay Of Fundy ◽  
Scotian Shelf ◽  
Transition Zones ◽  
Right Whale ◽  
Right Whales ◽  
Two Peaks ◽  
Copepod Biomass

Temperature, salinity, density of Zooplankton patches, and the abundance of right whales (Eubalaena glacialis glacialis) were measured concurrently during summer and autumn of 1983 and 1984 over the Grand Manan Basin, outer Bay of Fundy. Right whales appeared to exploit patches of copepods at densities greater than about 820/m3 (170 mg m−3). Patches were composed primarily of stage V Calanus finmarchicus at depths ≥ 100 m during daylight hours. Patch densities were similar in 1983 and 1984. Potential right whale feeding areas increased in extent from late July to October, with at least two peaks of copepod biomass occurring in 1984. Right whales appear to exploit euphausiid patches in the bay only incidentally; the whales departed in 1984 when euphausiid biomass was at a maximum. The topography of the basin, prevailing summer currents, and orientation of transition zones from mixed to stratified water all combine to facilitate accumulation of copepods from the Scotian Shelf and Gulf of Maine in the central lower Bay of Fundy. This area provides an important feeding ground for this stenophagous whale species.

scholarly journals Pollock (Pollachius virens) stock structure in the Canadian Maritimes inferred from mark-recapture studies

2006 ◽  
Vol 63 (4) ◽  
pp. 749-765 ◽  
Author(s):  
John D. Neilson ◽  
Wayne T. Stobo ◽  
Peter Perley
Keyword(s):  
Gulf Of Maine ◽  
Atlantic Coast ◽  
Fishing Effort ◽  
Management Unit ◽  
Bay Of Fundy ◽  
Stock Structure ◽  
Scotian Shelf ◽  
Current Management ◽  
Mark Recapture ◽  
Novel Method

Abstract The current management unit for pollock on the Canadian Atlantic coast is large compared with other gadoid resources, and includes the Scotian Shelf, the Bay of Fundy, and the Canadian portion of Georges Bank. Based on an analysis of mark-recapture studies conducted in the Canadian Maritimes and off southwestern Newfoundland and a review of other published studies providing data relevant to stock identification, the stock structure of pollock in Canadian Atlantic waters was re-assessed. The analysis also includes a novel method for using the spatial distribution of standardized fishing effort to predict the distribution of tag returns. It is concluded that three stocks co-occur within the current management unit. The larger population components exist in the western Scotian Shelf (including the eastern Bay of Fundy) and on the eastern Scotian Shelf. There is a coastal population in the western Gulf of Maine that overlaps into Canadian waters, but its size is likely to be relatively small. There is a need to revise the current management unit boundaries to protect the eastern Scotian Shelf stock, which on the basis of growth rate data, appears to be the least productive component of the pollock resource in Canadian Atlantic waters.

Helminth parasites of the alimentary tract of Atlantic halibut (Hippoglossus hippoglossus L.) and Greenland halibut (Reinhardtius hippoglossoides (Walbaum)) on the Scotian Shelf

1989 ◽  
Vol 67 (6) ◽  
pp. 1476-1481 ◽  
Author(s):  
James S. Scott ◽  
Shelley A. Bray
Keyword(s):  
Parasite Prevalence ◽  
Fish Length ◽  
Atlantic Halibut ◽  
Helminth Parasites ◽  
Intermediate Hosts ◽  
Scotian Shelf ◽  
Greenland Halibut ◽  
Hippoglossus Hippoglossus ◽  
Greenland Halibut Reinhardtius Hippoglossoides ◽  
Reinhardtius Hippoglossoides

Examination of the alimentary tracts of 272 Atlantic halibut (Hippoglossus hippoglossus (L.)) and 71 Greenland halibut (Reinhardtius hippoglossoides (Walbaum)) from the Scotian Shelf yielded a total of 25 helminth parasite species, 23 from H. hippoglossus (16 Digenea, 3 Cestoda, 2 Acanthocephala, 2 Nematoda) and 16 from R. hippoglossoides (11 Digenea, 3 Cestoda, 1 Acanthocephala, 1 Nematoda). Parasite prevalence and intensity were low (< 50% and < 10%, respectively) in both hosts, except for Derogenes varicus and Steganoderma formosum in H. hippoglossus and anisakid nematodes in R. hippoglossoides. Consideration of change in parasite prevalence and mean intensity in relation to fish length and diet suggests fish prey as transport hosts for D. varicus in larger halibuts, and crustaceans as the intermediate hosts for S. formosum before transmission to its principal host, H. hippoglossus. Geographical change in parasite prevalence and intensity was in the form of southwest to northeast clines along the Shelf, probably related to environmental factors. There was no evidence for stock differentiation in either of the hosts based on parasite fauna.

Sources of Water Contributed to the Bay of Fundy by Surface Circulation

1960 ◽  
Vol 17 (2) ◽  
pp. 181-197 ◽  
Author(s):  
Dean F. Bumpus
Keyword(s):  
Surface Water ◽  
Annual Cycle ◽  
Gulf Of Maine ◽  
Surface Flow ◽  
Bay Of Fundy ◽  
Georges Bank ◽  
Scotian Shelf ◽  
Eastern Side ◽  
Surface Circulation ◽  
Surface Drift

The returns from the 35,000 drift bottles launched in the Gulf of Maine area since 1919 have been analyzed to determine the annual cycle of surface drift. The source of surface flow into the Bay of Fundy expands from a minimum during January in the offing of the eastern side of the bay to a maximum in May which includes most of Georges Bank, the Gulf of Maine and the southwestern Scotian Shelf, then commencing in September gradually contracts toward the minimum.Secular variations in the removal of surface water from the Bay of Fundy, indicative of changes in the Maine eddy, were noted during 1957 and 1958.

Pollock (Pollachius virens (L.)) in the Bay of Fundy

1963 ◽  
Vol 20 (5) ◽  
pp. 1267-1314 ◽  
Author(s):  
D. H. Steele
Keyword(s):  
Growth Rate ◽  
Gulf Of Maine ◽  
Biased Sampling ◽  
Bay Of Fundy ◽  
Large Fish ◽  
Scotian Shelf ◽  
Western Atlantic ◽  
Dominant Type ◽  
Sublittoral Zone ◽  
Mature Fish

Observations made on the biology of the pollock in the western Atlantic, and primarily in the Bay of Fundy region of the northern Gulf of Maine, are presented. The largest landings of pollock in the western Atlantic are made in this area (ICNAF Division 4X). The best catches of large fish are made at temperatures above 1.1 °C, at depths of 20–100 fathoms (35–185 m) on the edges of shoals and banks where food is abundant. Spawning occurs in the winter and takes place in the southern Gulf of Maine and probably also on the Scotian Shelf, but not in the northern Gulf of Maine. The Bay of Fundy pollock are recruited from spawning in the southern Gulf of Maine and possibly on the Scotian Shelf. The pollock found in the Bay of Fundy appear to remain separate from those of the southern Gulf of Maine and the Scotian Shelf in the summer, but migrate south, spawn and probably mix with those of the southern Gulf of Maine, and possibly also those of the Scotian Shelf in the winter. The offshore pollock have a regular gradient in size across the Bay of Fundy; large fish (65–85 cm) are caught on the New Brunswick side, medium-sized fish (60–75 cm) around Grand Manan and smaller fish (45–60 cm) off western Nova Scotia. Catches with different size compositions are also found in small areas. Segregation by size into schools is therefore an important feature of pollock behaviour. The growth rate of pollock is rapid until the approximate time of sexual maturity, which occurs at ages of 4–7 years (50–65 cm) in the males and 5–7 years (55–70 cm) in the females. The growth rate of the immature and young, mature fish is similar to that recorded for other areas, but the older, mature fish appear to grow more slowly. It is suggested that this discrepancy may be due to biased sampling of the old fish in the Bay of Fundy due to the segregation by size. The 0-class pollock found in the shallow, sublittoral zone feed mainly on algae-inhabiting organisms and to a lesser extent on plankton. The 1-year-olds in the same location have a similar diet but consume a greater proportion of planktonic animals. The larger, offshore pollock in the Bay of Fundy are predominantly plankton eaters, and the euphausiid Meganyctiphanes norvegica is by far the most important organism in the diet. On the Scotian Shelf and in the Laurentian Channel fish is the dominant type of food, except for the smallest sizes of pollock.

Occurrence of alimentary tract helminth parasites of pollock (Pollachius virens L.) on the Scotian Shelf

1985 ◽  
Vol 63 (7) ◽  
pp. 1695-1698 ◽  
Author(s):  
J. S. Scott
Keyword(s):  
Alimentary Tract ◽  
Helminth Species ◽  
Fish Length ◽  
Fish Diet ◽  
Helminth Parasites ◽  
Scotian Shelf ◽  
Or Groups ◽  
Marine Parasites ◽  
Anisakid Nematodes ◽  
Support Evidence

Examination of the alimentary tracts of 456 pollock (Pollachius virens L.) revealed the presence of 15 helminth species or groups representing four phyla. Prevalence ranged from 76.6 in anisakid nematodes to negligible levels (<1.0) in some other species, with "ubiquitous" marine parasites Derogenes varicus, Hemiurus levinseni, anisakid nematodes, and Echinorhynchus gadi showing highest values. Changes in prevalence were related to a change from a largely crustacean diet to a largely fish diet with increasing fish length. Differences in prevalence of the more common parasites between the central and southwestern Scotian Shelf support evidence for separate pollock populations in the two areas.

Helminth parasites of Jamaican anoles (Reptilia: Iguanidae): variation in prevalence and intensity with host age and sex in a population of Anolis lineatopus

Parasitology ◽  
1987 ◽  
Vol 94 (2) ◽  
pp. 399-404 ◽  
Author(s):  
P. Vogel ◽  
D. A. P. Bundy
Keyword(s):  
Direct Relationship ◽  
Helminth Parasite ◽  
Infection Prevalence ◽  
Helminth Parasites ◽  
Host Age ◽  
Almost All ◽  
Low Prevalence ◽  
Age Range ◽  
Age And Sex

SUMMARYThe Jamaican iguanid lizard Anolis lineatopus is the host of 4 species of helminth parasite: an acanthocephalan (Centrorhynchus spinosus), a digenean (Mesocoelium danforthi), and 2 nematodes (Cyrtosumum scelopori and Thelandros (?cubensis). Prevalance of C. spinosus was unrelated to host age but was considerably higher in males (43%) than in females (10%). The intensity increased with host age: (range: 1–23, median: 3). Prevalence of C. scelopori increased with host age in both sexes: juveniles (<3 months) were uninfected while infection occurred in almost all lizards older than 9 months. Intensity was higher in males (range: 1–403, median: 158) than in females (range: 1–297, median: 86). The infection patterns of C. spinosus and C. scelopori differed significantly from each other and were not consistent with a simplistic direct relationship between time of exposure and infection prevalence. Acanthocephalan and digenean infections occurred at low prevalence and intensity although prevalence in older, larger lizards tended to be higher than in younger, smaller ones.

scholarly journals Seasonal trends and phenology shifts in sea surface temperature on the North American northeastern continental shelf

Elem Sci Anth ◽  
2017 ◽  
Vol 5 ◽  
Author(s):  
Andrew C. Thomas ◽  
Andrew J. Pershing ◽  
Kevin D. Friedland ◽  
Janet A. Nye ◽  
Katherine E. Mills ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Continental Shelf ◽  
Sea Surface Temperature ◽  
North American ◽  
Gulf Of Maine ◽  
Sea Surface ◽  
Scotian Shelf ◽  
Seasonal Differences ◽  
Study Region ◽  
The North

The northeastern North American continental shelf from Cape Hatteras to the Scotian Shelf is a region of globally extreme positive trends in sea surface temperature (SST). Here, a 33-year (1982–2014) time series of daily satellite SST data was used to quantify and map spatial patterns in SST trends and phenology over this shelf. Strongest trends are over the Scotian Shelf (&gt;0.6°C decade–1) and Gulf of Maine (&gt;0.4°C decade–1) with weaker trends over the inner Mid-Atlantic Bight (~0.3°C decade–1). Winter (January–April) trends are relatively weak, and even negative in some areas; early summer (May–June) trends are positive everywhere, and later summer (July–September) trends are strongest (~1.0°C decade–1). These seasonal differences shift the phenology of many metrics of the SST cycle. The yearday on which specific temperature thresholds (8° and 12°C) are reached in spring trends earlier, most strongly over the Scotian Shelf and Gulf of Maine (~ –0.5 days year–1). Three metrics defining the warmest summer period show significant trends towards earlier summer starts, later summer ends and longer summer duration over the entire study region. Trends in start and end dates are strongest (~1 day year–1) over the Gulf of Maine and Scotian Shelf. Trends in increased summer duration are &gt;2.0 days year–1 in parts of the Gulf of Maine. Regression analyses show that phenology trends have regionally varying links to the North Atlantic Oscillation, to local spring and summer atmospheric pressure and air temperature and to Gulf Stream position. For effective monitoring and management of dynamically heterogeneous shelf regions, the results highlight the need to quantify spatial and seasonal differences in SST trends as well as trends in SST phenology, each of which likely has implications for the ecological functioning of the shelf.

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