Metal contaminants for modelling lobster (Homarus americanus) migration patterns in the Inner Bay of Fundy, Atlantic Canada

2002 ◽  
Vol 44 (2) ◽  
pp. 134-141 ◽  
Author(s):  
C.L Chou ◽  
L.A Paon ◽  
J.D Moffatt
1986 ◽  
Vol 43 (11) ◽  
pp. 2291-2294 ◽  
Author(s):  
S. L. Waddy ◽  
D. E. Aiken

Large female American lobsters, Homarus americanus (> 120 mm carapace length), maintained at nearshore Bay of Fundy temperatures often spawn twice without an intervening molt (consecutive spawning). Consecutive spawning occurs in two forms: successive-year (spawning in two successive summers, a molt in the first and fourth years) and alternate-year (spawning in alternate summers, a molt in the first and fifth years). In both types, females often are able to fertilize the two successive broods with the sperm from a single insemination (multiple fertilization). Twenty of 21 large females that were held for up to 13 yr displayed one of these types of consecutive spawning. Consecutive spawning and multiple fertilization enable large lobsters to spawn more frequently over the long term than their smaller counterparts. This, combined with the logarithmic relationship between body size and numbers of eggs produced, means that very large lobsters have a much greater relative fecundity than previously thought.


1986 ◽  
Vol 92 (3) ◽  
pp. 393-404 ◽  
Author(s):  
A. Campbell ◽  
A. B. Stasko

1982 ◽  
Vol 39 (2) ◽  
pp. 326-334 ◽  
Author(s):  
D. W. Kulka ◽  
S. Corey ◽  
T. D. Iles

Seven species of euphausiids were found in the Bay of Fundy: Meganyctiphanes norvegica, Thysanoessa inermis, T. longicaudata, T. raschii, T. gregaria, Euphausia krohnii, and Nematoscelis megalops (listed in descending order of abundance). A high-intensity sampling scheme during November and March facilitated detailed distributional studies which revealed that M. norvegica, T. inermis, and T. longicaudata each had a specific stationary center of abundance in the study area, and each species performed a different pattern of diurnal vertical migration. Meganyctiphanes norvegica formed 90% (constituting 70 kt) of the euphausiids. The last four species were occasional immigrants from areas south of the Bay of Fundy. From the relationships between life history stages, vertical migration patterns, distribution, and currents in the Fundy Region, we suggest that these euphausiid species form stocks.Key words: euphausiids, Meganyctiphanes norvegica, Thysanoessa inermis, Thysanoessa longicaudata, biomass, community structure, stock, Bay of Fundy


2014 ◽  
Vol 83 ◽  
pp. 64-85 ◽  
Author(s):  
Brian J. Todd ◽  
John Shaw ◽  
Michael Z. Li ◽  
Vladimir E. Kostylev ◽  
Yongsheng Wu
Keyword(s):  

1983 ◽  
Vol 40 (10) ◽  
pp. 1667-1675 ◽  
Author(s):  
Alan Campbell

Sphyrion-tagged lobsters recaptured in the Bay of Fundy during 1977–80 yielded mean annual molt increment and molt probability data for male and female lobsters of 60–171 mm carapace length from which growth curves were calculated. In addition, a multiple regression model was used to generate growth curves from premolt size, number of molt periods lobsters were exposed to, and growth increment data for 850 tagged lobsters at liberty for 1–5 yr. Von Bertalanffy parameters were calculated from these empirical growth curves, which suggest that lobsters take 20–35 yr from time of hatching to reach 200 mm carapace length in the Bay of Fundy. Analysis of pleopods indicated that the majority of lobsters molt during August–October each year. Growth per molt of immature (60–94 mm carapace length) and mature (95–170 mm carapace length) male and immature female lobsters was arithmetic (regression slope 1.04) but was regressive for mature females (slope 0.95). Mature lobsters molted less frequently than immature lobsters, but mature males grew more rapidly than mature females. Most mature females in the Bay of Fundy are on a 2-yr molt–reproductive cycle. About 20% of ovigerous females recaptured within 2 yr after release had extruded eggs a second time without molting, confirming that multiple egg extrusions between molts do occur naturally.


2015 ◽  
Vol 72 (5) ◽  
pp. 728-741 ◽  
Author(s):  
A. Jamie F. Gibson ◽  
Edmund A. Halfyard ◽  
Rod G. Bradford ◽  
Michael J.W. Stokesbury ◽  
Anna M. Redden

Telemetry is increasingly being used to estimate population-level survival rates. However, these estimates may be affected by the detectability of telemetry tags and are reliant on the assumption that telemetry data represent the movements of the tagged fish. Predation on tagged fish has the potential to bias survival estimates, and unlike the issue of detectability, methods to correct for the resulting bias (termed “predation bias”) are not yet developed. In an acoustic telemetry study on inner Bay of Fundy Atlantic salmon (Salmo salar) smolts during 2008 and 2011, unusual tag detection patterns were indicative that some data may have been representative of the movements of predators rather than smolts. To incorporate predation effects into the resulting survival estimates, a suite of 11 summary migration metrics were compared between Atlantic salmon smolts and striped bass (Morone saxatilis). Cluster analyses revealed that 2.4% to 13.6% of tags implanted in smolts exhibited migration patterns more similar to striped bass than to other smolts, which was interpreted here as evidence of predation. Reassigning the fate of these tags as “depredated–died” reduced estimated survival from 43.5% to 41.1% in 2008 and from 32.6% to 19.0% in 2011 relative to a traditional mark–recapture model, illustrating the effect of predation bias in this case study.


2021 ◽  
Author(s):  
Benjamin de Jourdan ◽  
Tahereh Boloori ◽  
Les Burridge

Abstract Standard model species are commonly used in toxicity tests due to their biological and technical advantages but studying native species increases the specificity and relevance of results generated for the potential risk assessment to an ecosystem. Accounting for intraspecies variability and other factors, such as chemical and physical characterization of test medium, is necessary to develop a reproducible bioassay for toxicity testing with native species. In this study, larval stage I American lobster (Homarus americanus) was selected as the test species, which is native to Atlantic Canada. Toxicity tests were first conducted exposing lobster larvae to a reference toxicant of copper sulfate (CuSO4) and then to physically and chemically dispersed oil. The effect on larval survival was estimated by calculating the median effect concentration (EC50) as 2.54-9.73 mg TPH/L when all trials are considered together. The HC5 or PNEC value was 2.52 mg TPH/L and therefore a narrow difference from the EC50 value. The inter-trial variability (coefficient of variability = 17%) was lower than the US Environmental Protection Agency standard test species of mysid shrimp (Americamysis bahia) and inland silversides (Menidia bervillina). Our results indicate that the described larval lobster bioassay is reliable to produce repeatable results for this commercially important and native species of Atlantic Canada.


Sign in / Sign up

Export Citation Format

Share Document