Organochlorine Contaminants in Avian Wildlife of Severn Sound

1995 ◽  
Vol 30 (4) ◽  
pp. 693-712 ◽  
Author(s):  
Pamela A. Martin ◽  
D. Vaughn Weseloh ◽  
Christine A. Bishop ◽  
Karin Legierse ◽  
Birgit Braune ◽  
...  
Keyword(s):  
Lake Ontario ◽  
Lake Huron ◽  
Breast Muscle ◽  
Tree Swallow ◽  
Tree Swallows ◽  
Herring Gulls ◽  
Terrestrial Arthropods ◽  
Common Terns ◽  
Organochlorine Contaminants ◽  
Caspian Terns

Abstract Organochlorine contaminants were measured in pooled egg samples of colonial waterbirds, red-winged blackbirds and tree swallows breeding in or near Severn Sound, Lake Huron, an area designated by the International Joint Commission as an Area of Concern, during 1991. Breast muscle samples of staging waterfowl were also collected the preceding autumn. PCBs, DDE and mirex were the most prevalent organochlorine contaminants present in eggs (concentration ranges of 0.065 to 5.452, 0.118 to 3.12 and 0.007 to 0.174 mg/kg, respectively), while oxychlordane, cis-chlordane, dieldrin, heptachlor epoxide, trans-nonachlor, cis-nonachlor, OCS, HCB and beta-HCH were also detectable at low levels in some egg samples. Tetra- and pentachlorobenzene, and alpha-and gamma-HCH were not detected in any of the samples. Generally, the following interspecific gradient in contaminant levels in bird eggs was found: herring gulls = Caspian terns > common terns > tree swallows > blackbirds. Concentrations in the eggs of piscivorous birds in Severn Sound were similar or slightly lower than those from other colonies in Georgian Bay and Lake Huron, and considerably lower than those from colonies in Hamilton Harbour, Lake Ontario. Mirex levels in herring gulls and Caspian terns from Severn Sound colonies were an exception in that they were substantially higher than levels from other Lake Huron colonies (0.174 and 0.167 mg.kg-1 for the two species, respectively, versus <0.12 mg.kg-1), although still much lower than those from Lake Ontario (0.50 and 0.719, respectively). It is probable that mirex was accumulated by gulls and terns during winter or migrational stopovers on Lake Ontario. Low contaminant levels in common terns may have been a result of their consumption of a smaller size class of prey fish. Higher contaminant levels in tree swallow eggs in comparison to red-winged blackbird eggs may have been due to the preponderance of aquatic insects in their diets, as opposed to the larger proportion of terrestrial arthropods in blackbird diets. Only PCBs and DDE were detected in the breast muscle of lesser scaup and mallards.

Novel method for monitoring common terns at a large colony in northern Lake Huron, USA

2017 ◽  
Vol 43 (6) ◽  
pp. 1160-1164
Author(s):  
R. Gregory Corace ◽  
Shelby A. Weiss ◽  
Dawn S. Marsh ◽  
Ellen L. Comes ◽  
Francesca J. Cuthbert
Keyword(s):  
Lake Huron ◽  
Common Terns ◽  
Large Colony ◽  
Novel Method

Rainfall and nest site competition delay Mountain Bluebird and Tree Swallow breeding but do not impact productivity

The Auk ◽  
2020 ◽  
Vol 137 (2) ◽  
Author(s):  
Anna Drake ◽  
Kathy Martin
Keyword(s):  
Daily Rainfall ◽  
Tree Swallow ◽  
Tree Swallows ◽  
Breeding Phenology ◽  
Productivity Cost ◽  
Breeding Sites ◽  
Tree Cavities ◽  
Mountain Bluebird ◽  
Mountain Bluebirds ◽  
Study Sites

Abstract Optimizing breeding phenology, an important aspect of fitness, is complex for migratory species as they must make key timing decisions early, and remotely, from breeding sites. We examined the role of weather (locally and cross-seasonally), cavity availability, and competitive exclusion in determining among-year variation in breeding phenology over 17 yr for 2 migratory, cavity-nesting birds: Mountain Bluebirds (Sialia currucoides; n = 462 nests) and Tree Swallows (Tachycineta bicolor; n = 572) using natural tree cavities in British Columbia, Canada. We assessed weather effects within the winter and migratory range and at our study sites. We quantified competition as the proportion of cavities occupied by European Starlings (Sturnus vulgaris) (for both species) and Mountain Bluebirds (for Tree Swallow only) in each year. For 229 bluebird and 177 swallow nests with known fates, we tested whether late years resulted in reduced productivity. Although the effects were small, heavy rainfall and strong diurnal westerly winds during migration were associated with breeding delays for Mountain Bluebirds. However, cavity availability (earlier breeding with increases) had a 5–8 × greater effect on timing than migratory conditions. There was no evidence that starling competition delayed bluebirds. In Tree Swallows, greater local daily rainfall was associated with delayed breeding, as was starling abundance (the effect of starlings was 1.4 × smaller than that of rainfall). Neither bluebird abundance nor cavity availability changed swallow phenology. Neither species showed reduced productivity in late breeding years. In both species, individuals that bred late relative to conspecifics within-year had smaller clutches and greater probability of nest failure. We conclude that breeding ground conditions, particularly cavity limitation and local rainfall (for swallows), are important drivers of breeding phenology for our focal species, but that the productivity cost of late years, at least for Tree Swallows, is minimal.

scholarly journals Diet of the Nestling Tree Swallow

The Condor ◽  
2004 ◽  
Vol 106 (2) ◽  
pp. 423-429 ◽  
Author(s):  
Jean M. Mengelkoch ◽  
Gerald J. Niemi ◽  
Ronald R. Regal
Keyword(s):  
Open Water ◽  
Time Of Day ◽  
Tachycineta Bicolor ◽  
Tree Swallow ◽  
Tree Swallows ◽  
Larval Stages ◽  
Terrestrial Origin ◽  
The Mean ◽  
Foraging Radius

Abstract Dietary samples from nestling Tree Swallows (Tachycineta bicolor) in northwestern Minnesota were compared to invertebrate availability as measured by aerial tow nets. The majority of the biomass in the nestlings' diet was adult insects with larval stages of aquatic origin, while absolute numbers of insects of both aquatic and terrestrial origin were similar. Orders of invertebrates in the diet and available were similar in number but not in biomass. Diet showed little variation by time of day, date of sampling or the age of the nestling. The mean number of odonates in the nestling Tree Swallows' diet increased exponentially as the percentage of open water and open water + cattail marsh increased within a 400-m foraging radius. Dieta de los Pichones de Tachycineta bicolor Resumen. Se compararon muestras dietarias de pichones de la golondrina Tachycineta bicolor tomadas en el noroeste de Minnesota con la disponibilidad de invertebrados medida con redes aéreas. La mayor parte de la biomasa en la dieta de los pichones correspondió a insectos adultos con estadíos larvales de origen acuá tico, mientras que los números absolutos de insectos de origen acuático y no acuático fueron similares. Los órdenes de invertebrados presentes en la dieta y disponibles en el ambiente fueron similares en números pero no en biomasa. La dieta mostró poca variación entre horas del día, fechas de muestreo o edad de los pichones. El número promedio de odonatos en la dieta de los pichones de T. bicolor aumentó exponencialmente a medida que se incrementó el porcentaje de agua abierta y de agua abierta + pantanos de espadañas dentro de un radio de forrajeo de 400 m.

The Frank Bay Site, Lake Nipissing, Ontario

1954 ◽  
Vol 20 (01) ◽  
pp. 40-50 ◽  
Author(s):  
Frank Ridley
Keyword(s):  
Igneous Rock ◽  
Lake Ontario ◽  
17Th Century ◽  
Coarse Sand ◽  
Lake Huron ◽  
The South ◽  
Low Area ◽  
South Shore ◽  
The One ◽  
French River

Lake Nipissing is situated 230 miles north of Lake Ontario and roughly 140 miles within the igneous rock territory. Some 30 by 8 miles in size, it is drained westerly by the French River into Lake Huron. Frank Bay, enclosing an area of one half square mile, is situated on the south shore at the entrance to the French River. Historically the area was occupied by an Algonkian group called “Nipisinieries” or “Nipissings” by the 17th century Jesuits; Galinee's map of 1665 depicts a bay on the south shore of Lake Nipissing at the head of the French River: “In a bay at this place the Nipissings usually locate their village” (Coyne, 1903). The site described here, probably the one figured by Galinee, is a level tract of about one half acre constructed by wave deposition of coarse sand upon a low area at the bottom of the bay.

scholarly journals Genetic population structure of the round whitefish (Prosopium cylindraceum) in North America: multiple markers reveal glacial refugia and regional subdivision

2018 ◽  
Vol 75 (6) ◽  
pp. 836-849 ◽  
Author(s):  
Thomas D. Morgan ◽  
Carly F. Graham ◽  
Andrew G. McArthur ◽  
Amogelang R. Raphenya ◽  
Douglas R. Boreham ◽  
...  
Keyword(s):  
Population Structure ◽  
North America ◽  
Great Lakes ◽  
Lake Ontario ◽  
Glacial Refugia ◽  
Lake Huron ◽  
Genetic Population Structure ◽  
Population Subdivision ◽  
Source Population ◽  
Genetic Population

Round whitefish (Prosopium cylindraceum) have a broad, disjunct range across northern North America and Eurasia, and little is known about their genetic population structure. We performed genetic analyses of round whitefish from 17 sites across its range using nine microsatellites, two mitochondrial DNA (mtDNA) loci, and 4918 to 8835 single-nucleotide polymorphism (SNP) loci. Our analyses identified deep phylogenetic division between eastern and western portions of the range, likely indicative of origins from at least two separate Pleistocene glacial refugia. Regionally, microsatellites and SNPs identified congruent patterns in subdivision, and population structure was consistent with expectations based on hydrologic connectivity. Within the Laurentian Great Lakes, Lake Huron and Lake Ontario were identified as key areas of interest. Lake Huron appears to be a contemporary source population for several other Great Lakes, and Lake Ontario contains a genetically discrete group of round whitefish. In all cases, multiple genetic markers yielded similar patterns, but SNPs offered substantially enhanced resolution. We conclude that round whitefish have population subdivision on several scales important for understanding their evolutionary history and conservation planning.

Phosphorus Enrichment, Silica Utilization, and Biogeochemical Silica Depletion in the Great Lakes

1986 ◽  
Vol 43 (2) ◽  
pp. 407-415 ◽  
Author(s):  
Claire L. Schelske ◽  
Eugene F. Stoermer ◽  
Gary L. Fahnenstiel ◽  
Mark Haibach
Keyword(s):  
Steady State ◽  
Great Lakes ◽  
Urban Population ◽  
Thermal Stratification ◽  
Lake Erie ◽  
Lake Michigan ◽  
Lake Ontario ◽  
Lake Huron ◽  
Phosphorus Enrichment

Our hypothesis that silica (Si) depletion in Lake Michigan and the severe Si depletion that characterizes the lower Great Lakes were induced by increased phosphorus (P) inputs was supported by bioassay experiments showing increased Si uptake by diatoms with relatively small P enrichments. We propose that severe Si depletion (Si concentrations being reduced to ≤0.39 mg SiO2∙L−1 prior to thermal stratification) results when P levels are increased to the extent that increased diatom production reduces Si concentrations to limiting levels during the thermally mixed period. Large P enrichments such as those that characterized the eastern and central basis of Lake Erie and Lake Ontario in the early 1970s are necessary to produce severe Si depletion. It is clear that severe Si depletion in the lower lakes was produced by P enrichment because inflowing waters from Lake Huron have smaller P concentrations and larger Si concentrations than the outflowing waters of either Lake Erie or Lake Ontario. Severe Si depletion probably began in the 1940s or 1950s as the result of increased P loads from expanded sewering of an increasing urban population and the introduction of phosphate detergents. The model proposed for biogeochemical Si depletion is consistent with previous findings of high rates of internal recycling because, under steady-state conditions for Si inputs, any increase in diatom production will produce an increase in permanent sedimentation of biogenic Si provided some fraction of the increased biogenic Si production is not recycled or unless there is a compensating increase in dissolution of diatoms.

Some implications of crustal movement in engineering planning

1970 ◽  
Vol 7 (2) ◽  
pp. 628-633 ◽  
Author(s):  
R. H. Clark ◽  
N. P. Persoage
Keyword(s):  
Great Lakes ◽  
Lake Ontario ◽  
Water Levels ◽  
Crustal Movement ◽  
Earth’S Crust ◽  
Lake Huron ◽  
Great Lakes Basin ◽  
Lake Outlet ◽  
Earth's Crust ◽  
Bodies Of Water

Movements of the earth's crust causing progressive changes in the levels of large bodies of water relative to their shorelines may influence the formulation of water resource projects and/or their continuing effectiveness with time. In the Great Lakes basin there is evidence of an uplift of the earth's crust, of about 1 ft per 100 y, in the northeasterly part of the basin relative to that in the southwest. This results in a corresponding lowering of water levels along the northeasterly shorelines and a rise in water levels along the southwest shores. In at least two of the lakes, Lake Huron and Lake Ontario, the average depth of water will change with time. In Lake Huron, it will gradually decrease because the bed underlying the lake is rising with respect to the lake outlet. In Lake Ontario, the depth of water will increase since the lake outlet is rising with respect to the remainder of the lake. This paper reviews some of the engineering implications of the relative rates of crustal movement in the Great Lakes region on long-term management of the water levels of the Great Lakes.

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