The Lobster (Homarus americanus) Fishery off Lower Argyle Southwestern Nova Scotia

1990 ◽  
Vol 47 (6) ◽  
pp. 1177-1184 ◽  
Author(s):  
Alan Campbell
Keyword(s):  
Nova Scotia ◽  
Fold Increase ◽  
Homarus Americanus ◽  
Weekly Basis ◽  
Index Numbers ◽  
Management Implications ◽  
Frequency Distributions ◽  
Fishing Season ◽  
Juvenile Abundance ◽  
Overall Mortality

Catch and effort data for the lobster (Homarus americanus) fishery of Lower Argyle, Nova Scotia, were obtained from sales slips on a weekly basis during 1978–87. Lobster size–frequency distributions were collected during at-sea sampling at the beginning and end of each fishing season. This fishery experienced a three-fold increase in landings (from 87.6 to 270 t) due to an increase in recruitment during the 10-yr study. The fishermen responded to the improved recruitment by increasing the total number of days fished per season by 41%. Overall mortality of recruited lobster (estimated from size–frequencies) rose from 55% in 1978 to 72–81% during 1985–87. During the 1987–88 fishing season, about 1 t lobster were removed per km2 of fishing grounds. Regression relationships between a prerecruit juvenile abundance index (numbers of lobster/trap haul) and the recruited yield one to two fishing seasons later were significantly correlated for 8–9 yr of data; equations predicted that lobster yields would remain high during the 1988–89 fishing season but decline in this area during 1989–90 fishing season. Management implications of forecasting recruitment yields 1–2 yr in advance and possible strategies to reduce major recruitment fluctuations in this fishery are discussed.

Spatial and Temporal Overlap of the American Lobster (Homarus americanus) and Sea Scallop (Placopecten magellanicus) as Related to the impact of Inshore Scallop Dragging

1992 ◽  
Vol 49 (7) ◽  
pp. 1486-1492 ◽  
Author(s):  
D. L. Roddick ◽  
R. J. Miller
Keyword(s):  
Nova Scotia ◽  
Homarus Americanus ◽  
Fishing Effort ◽  
The Other ◽  
American Lobster ◽  
Placopecten Magellanicus ◽  
Time And Space ◽  
Sea Scallop ◽  
The Impact ◽  
Temporal Overlap

Assessment of the damage of one fishery by another requires knowledge of the overlap, in time and space, of the damaging fishing effort and the abundance of the damaged species, as well as a measure of the rate of damage. This approach was used to measure the impact of inshore scallop dragging on lobsters in Nova Scotia. Areas of reported co-occurrence of lobster and scallop grounds were surveyed by divers to determine the extent of overlap. Only 2 of 52 sites surveyed had lobsters on scallop grounds that could be dragged. Divers surveyed one site six times during 1987 and 1988 and found lobsters most abundant during August and September. Only 2% of the lobsters in the path of scallop drags were either captured or injured. The estimated value of lobsters destroyed by dragging for scallops during periods of peak lobster abundance was minor: $757 at one site and $176 at the other. Restricting dragging to periods of low lobster abundance significantly reduces this cost.

scholarly journals Is the Frequency of Candidemia Increasing in COVID-19 Patients Receiving Corticosteroids?

2020 ◽  
Vol 6 (4) ◽  
pp. 286
Author(s):  
Cezar V. W. Riche ◽  
Renato Cassol ◽  
Alessandro C. Pasqualotto
Keyword(s):  
Antifungal Therapy ◽  
Potential Risk ◽  
Fold Increase ◽  
Hospitalized Patients ◽  
Anti Inflammatory ◽  
High Doses ◽  
Overall Mortality

Corticosteroids have potent anti-inflammatory and immunosuppressive effects. Recently, these medications have gained importance in the treatment of severe COVID-19. Here we present data demonstrating a marked (10-fold) increase in frequency of candidemia in hospitalized patients with COVID-19 receiving corticosteroids in Brazil. Overall mortality was 72.7%, despite antifungal therapy. Physicians should be aware of the potential risk for candidemia among severely ill COVID-19 patients receiving high-doses of corticosteroids.

scholarly journals Pseudoscorpiones and Scorpiones of Canada

ZooKeys ◽  
2019 ◽  
Vol 819 ◽  
pp. 67-72 ◽  
Author(s):  
Elyssa Cameron ◽  
Christopher M. Buddle
Keyword(s):  
Fold Increase ◽  
Index Numbers ◽  
High Level

Twenty-five species of pseudoscorpions are known from Canada, a five-fold increase since an assessment from 1979. The diversity and distribution of Canadian species are poorly known and at least 27 more species are expected to be found in the country. Currently 46 Barcode Index Numbers are assigned to Canadian specimens, suggesting a high level of undocumented diversity. Only one scorpion species is known from Canada and no other species are expected.

Laboratory and Field Tests of Modified Sphyrion Tags on Lobsters (Homarus americanus)

1970 ◽  
Vol 27 (2) ◽  
pp. 257-264 ◽  
Author(s):  
D. J. Scarratt
Keyword(s):  
Carapace Length ◽  
Field Tests ◽  
Homarus Americanus ◽  
Poor Survival ◽  
Internal Organs ◽  
Fishing Season ◽  
Tag Loss

Mortalities of lobsters held in the laboratory and tagged with sphyrion tags inserted dorsally between the carapace and abdomen (subcarapace tag) and between the second and third abdominal segments (abdomen tag) did not differ significantly. Premoult tag loss was negligible. The subcarapace tag was retained significantly better through moulting.Returns of subcarapace-tagged and abdomen-tagged lobsters released on the fishing grounds in June, 11 weeks before the August 10 opening of the fishing season, were lower than returns of carapace-tagged lobsters released in early August. More subcarapace-tagged than abdomen-tagged lobsters were returned, and a higher proportion had moulted. Growth was comparable to that reported in the literature. Few lobsters were recaptured during the following fishing season, 14–16 months after liberation, and none subsequently. Returns from lobsters less than 63.5 mm carapace length (sublegal) when tagged were extremely low. Poor survival may be related in part to time of release. Some injury to internal organs may occur with both tags. The subcarapace tag is clearly superior but may be of limited value in the field for lobsters below 63.5 mm carapace length.

scholarly journals Productivity of riverine habitats may be changing for American eel

2018 ◽  
Vol 75 (11) ◽  
pp. 1773-1777 ◽  
Author(s):  
Heather Dawn Bowlby
Keyword(s):  
Nova Scotia ◽  
Atlantic Coast ◽  
American Eel ◽  
Regional Productivity ◽  
Glass Eel ◽  
Watershed Characteristics ◽  
High Productivity ◽  
Enhanced Production ◽  
Juvenile Abundance ◽  
Riverine Habitats

The panmictic population of American eel (Anguilla rostrata) is at risk, making any region that supports enhanced production important from a recovery perspective. Strong glass eel runs to a small number of rivers along the Atlantic coast of Nova Scotia are thought to indicate high productivity, partially buffering declines occurring in other regions. However, contrary to glass eel indices of recruitment, an index representing older juveniles has strongly declined in riverine habitats throughout Nova Scotia from 1995 to 2005, with evidence of substantial differences in relative abundance among watersheds. This suggests that glass eel indices may not reflect trends of older juveniles and consequently that the contribution of Atlantic coast rivers to population persistence may be overstated. More recent monitoring from two rivers shows divergent trends in juvenile eel abundance, underscoring the importance of widespread surveys to assess changes in regional productivity. Further evaluation of the watershed characteristics associated with higher juvenile abundance would aid in understanding differences in productivity among watersheds and possibly in facilitating increased spawning escapement for American eel.

LIFE HISTORIES OF SOME COMMON SPIDERS FROM TREES AND SHRUBS IN NOVA SCOTIA

1961 ◽  
Vol 39 (6) ◽  
pp. 777-787 ◽  
Author(s):  
C. D. Dondale
Keyword(s):  
Nova Scotia ◽  
Life Histories ◽  
Carapace Width ◽  
Reproductive Maturity ◽  
Frequency Distributions ◽  
Two Generations ◽  
Trees And Shrubs

At Kentville, Nova Scotia, Araniella displicata (Hentz), Philodromus rufus Walckenaer, Philodromus cespiticolis Walckenaer, Paraphidippus marginatus (Walckenaer), and Metaphidippus protervus (Walckenaer) attained reproductive maturity in May and June. Eggs were laid in late June and early July. The young of A. displicata, P. rufus, and M. protervus began to appear in late July, while those of the remaining species began in early August. In A. displicata, P. rufus, P. cespiticolis, and P. marginatus there were two generations containing immature spiders at all times of the year, as indicated by frequency distributions of carapace width. It was concluded that these species are biennial in development. M. protervus, with only one generation containing immatures in any season, is annual.

scholarly journals Risk factors associated with soft-shelled lobsters (Homarus americanus) in southwestern Nova Scotia, Canada

FACETS ◽  
2017 ◽  
Vol 2 (1) ◽  
pp. 15-33 ◽  
Author(s):  
Krishna K. Thakur ◽  
Crawford Revie ◽  
Henrik Stryhn ◽  
Shannon Scott Tibbetts ◽  
Jean Lavallée ◽  
...  
Keyword(s):  
Nova Scotia ◽  
Homarus Americanus ◽  
Eastern Canada ◽  
Related Factors ◽  
Mixed Effect ◽  
Shell Quality ◽  
Factors Associated ◽  
Regression Methods ◽  
Spatio Temporal ◽  
Ecosystem Changes

Soft-shelled lobsters pose economic challenges to the lobster industry due to low meat yields and survivability during holding and transportation. Our objectives were to describe spatio-temporal patterns of soft-shelled lobsters in southwestern Nova Scotia, and identify environmental and lobster-related factors associated with shell quality. We analyzed data obtained from a broad-scale, intensive monitoring project and remotely sensed water temperatures. Mixed-effect logistic regression and linear regression methods analyzed more than 130 000 samples collected between 2004 and 2014. The annual overall prevalence of soft-shelled lobsters ranged from 9% to 38% and varied significantly among fishing areas. Shell quality was influenced by sex and size, and in the 2 months before the fishing season, lower water temperatures (4–6 weeks prior to sampling) were associated with reduced prevalence of soft-shells. High annual variability of soft-shell prevalence, that water temperature alone could not explain, suggests that adjusting fishing seasons, arbitrarily, in two fishing areas will not improve the overall shell quality of landed lobsters. Further research is needed to evaluate the effects of long-term temperature and ecosystem changes on lobster health in eastern Canada.

Nutrients in Salmonid Ecosystems: Sustaining Production and Biodiversity

2003 ◽  
Keyword(s):  
Oncorhynchus Mykiss ◽  
Coho Salmon ◽  
Maximum Yield ◽  
Fold Increase ◽  
Current Yield ◽  
Watershed Restoration ◽  
Nutrient Additions ◽  
Juvenile Abundance ◽  
Average Size ◽  
Size At Age

<em>Abstract.</em>—Positive numerical responses in steelhead <em>Oncorhynchus mykiss </em>and coho salmon <em>O. kisutch </em>juvenile abundance and size, smolt yield, and smolts per spawner were obtained from watershed restoration in the Keogh River on northern Vancouver Island, British Columbia. Annual increases coincided with treatment and were compared with data from an untreated neighboring watershed (Waukwaas River). The steelhead population, now apparently capable of thriving, was below replacement recruitment prior to the addition of inorganic nutrients and instream habitat structures, the key components of several restoration activities. Annual increases in summer densities of steelhead juveniles were recorded as the rehabilitation treatments progressed from 1997 to 2000. Estimation of steelhead parr densities indicated a 3.8-fold increase over pretreatment or internal untreated values; increases in sites with both inorganic nutrient briquettes and habitat structure additions were 2.5–1.9 times higher than sites with nutrient additions or habitat structures alone. Average size-at-age of juvenile salmonids, by autumn, significantly increased through the years of rehabilitation treatment and compared with fish in the Waukwaas River. Steelhead smolt yield in 2000 increased to 2,338 fish, the highest yield since 1993, but lower than the historical average (>6,000) due to low escapement. Current yield was an improvement over the historic low (<1,000 steelhead smolts, 1998). Coho smolt yield increased to 74,500 or 20% above the historic average (62,000 smolts; 1975–1999), well above the record low counts of 1998 (22,000), but below the historic maximum yield (105,000; 1981). A significant increase in steelhead smolt recruitment at low escapement, from less than 2 to greater than 50 smolts per spawner, was observed over the last four brood years (1995–1998). The assessment now shifts to further benefits to smolt yield, which will require evaluation to 2004.

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