Patterns of genetic diversity in Great Lakes bloaters (Coregonus hoyi) with a view to future reintroduction in Lake Ontario

2007 ◽  
Vol 9 (2) ◽  
pp. 281-293 ◽  
Author(s):  
Marie-Julie Favé ◽  
Julie Turgeon
1996 ◽  
Vol 31 (2) ◽  
pp. 411-432 ◽  
Author(s):  
Michael E. Comba ◽  
Janice L. Metcalfe-Smith ◽  
Klaus L.E. Kaiser

Abstract Zebra mussels were collected from 24 sites in Lake Erie, Lake Ontario and the St. Lawrence River between 1990 and 1992. Composite samples of whole mussels (15 sites) or soft tissues (9 sites) were analyzed for residues of organochlo-rine pesticides and PCBs to evaluate zebra mussels as biomonitors for organic contaminants. Mussels from most sites contained measurable quantities of most of the analytes. Mean concentrations were (in ng/g, whole mussel dry weight basis) 154 ΣPCB, 8.4 ΣDDT, 3.5 Σchlordane, 3.4 Σaldrin, 1.4 ΣBHC, 1.0 Σendosulfan, 0.80 mirex and 0.40 Σchlorobenzene. Concentrations varied greatly between sites, i.e., from 22 to 497 ng/g for ΣPCB and from 0.08 to 11.6 ng/g for ΣBHC, an indication that mussels are sensitive to different levels of contamination. Levels of ΣPCB and Σendosulfan were highest in mussels from the St. Lawrence River, whereas mirex was highest in those from Lake Ontario. Overall, mussels from Lake Erie were the least contaminated. These observations agree well with the spatial contaminant trends shown by other biomoni-toring programs. PCB congener class profiles in zebra mussels are also typical for nearby industrial sources, e.g., mussels below an aluminum casting plant contained 55% di-, tri- and tetrachlorobiphenyls versus 31% in those upstream. We propose the use of zebra mussels as biomonitors of organic contamination in the Great Lakes.


Author(s):  
Aaron Styba

In one of the most ignominious wars in history, a combined force of British and Canadian soldiers, sailors and civilians constructed the largest wooden warship ever built in the western hemisphere. Engaged with the Americans in a desperate game of cat-and-mouse upon Lake Ontario, the massive warship HMS St. Lawrence swung the balance of power firmly in favour of the British and thereby hastened the signing of the Treaty of Ghent, bringing the War of 1812 to a sputtering halt.This colossal warship, over 200 feet long, crewed by 700 and carrying 112 cannon, was completed at Kingston, Ontario in little over 9 months. Patrolling Lake Ontario, HMS St. Lawrence immediately caused the Americans to flee to their harbour. Astoundingly, and in a very Canadian fashion, she never fired a shot in combat.After the war ended, years of disrepair and dereliction left HMS St. Lawrence as a hulk of her former self. Sold to a local entrepreneur for a measly £25, she found herself towed to a location near Queen’s University. Mysteriously, she then disappeared from history. After the consideration of several theories, the hope is that this presentation, based upon the research conducted in a joint investigation by Parks Canada, the Marine Museum of the Great Lakes and Queen’s University, will help determine the fate of this “nuclear bomb of her age.”This presentation will outline the fascinating origins of HMS St. Lawrence, how she was archaeological documented, what the investigation tells us, and why investigating naval heritage is a worthy undertaking.


Botany ◽  
2010 ◽  
Vol 88 (3) ◽  
pp. 250-257 ◽  
Author(s):  
Martha Gauthier ◽  
Emily Crowe ◽  
Lindsey Hawke ◽  
Neil Emery ◽  
Paul Wilson ◽  
...  

Pitcher's thistle ( Cirsium pitcheri Torr. ex Eaton (Torr. & Gray)) is a Great Lakes endemic that in Canada is designated as threatened at both the provincial (Ontario) and national levels. Management plans will benefit from conservation genetic data, which can provide insight into population genetic diversity and differentiation. We obtained genetic data from nuclear and chloroplast microsatellite markers from 17 populations of C. pitcheri around the Great Lakes. The nuclear data revealed overall low levels of diversity, high levels of inbreeding, and low levels of population connectivity. The chloroplast data identified a single haplotype, which is consistent with reduced genetic diversity following postglacial colonization. The high levels of inbreeding within populations will likely pose a serious threat to populations in the short term; these have resulted from a combination of low connectivity between populations, and small and fluctuating population sizes. Future management of C. pitcheri populations should consider human-mediated dispersal of plants or seeds among sites.


1992 ◽  
Vol 49 (7) ◽  
pp. 1501-1506 ◽  
Author(s):  
Bernie May ◽  
J. Ellen Marsden

In this paper we report the discovery and implications of a second nonindigenous species of dreissenid mussel in the Great Lakes. This species was detected in a routine screening of zebra mussels (Dreissena polymorpha) for allozyme variability. The two species differ at allozyme loci (Nei's I = 0.30 using 12 loci) and in their shell morphology (the second species lacks the acute angle, or carina, between the ventral and dorsal surfaces of the shell of the zebra mussel). As a working name, at least until its species identity is discovered, we have called the new species the "quagga mussel." Currently, this mussel occurs in Lake Ontario in equal frequencies with D. polymorpha. Its low frequency of occurence in neighboring waters (e.g. the Erie canal, Niagara River, and outlet to Onondaga Lake) and lack of occurrence in any of the other Great Lakes suggest that (1) its point of introduction to North America was in Lake Ontario and (2) its range may expand.


1999 ◽  
Vol 56 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Hugh J MacIsaac ◽  
Igor A Grigorovich ◽  
James A Hoyle ◽  
Norman D Yan ◽  
Vadim E Panov

Cercopagis pengoi, a waterflea native to the Ponto-Caspian region, was discovered during 1998 in Lake Ontario. Individuals were found throughout the lake during summer snagged on sportfishing lines. The population included parthenogenetic (92%) and sexual (2%) females and males (6%). Cercopagis has a very long caudal appendage that is more than five times the body length and terminates in a distinctive loop. Females and males from Lake Ontario were significantly smaller than individuals from the Neva Estuary, Baltic Sea. In Eurasia, C. pengoi occurs in relatively warm fresh and brackish waters (0-14‰) at population densities usually <3000 individuals·m-3; mean and maximum population densities in Lake Ontario were 170 and 322 individuals·m-3, respectively. The presence of females with resting eggs indicates that Cercopagis will likely establish in Lake Ontario. As with other recently introduced invertebrates, Cercopagis likely was transported to the Great Lakes in ballast water from eastern Europe. The rapid influx of Ponto-Caspian species into the Great Lakes warrants further study including identification of source populations, mechanisms of dispersal, impacts on recipient ecosystems, and efficacy of ballast water exchange programs.


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