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Full-Text Articles in Biodiversity

Identification, Enumeration And Diversity Of Nitrifying Planktonic Archaea And Bacteria In Trophic End Members Of The Laurentian Great Lakes, Maitreyee Mukherjee, Anirban Ray, Anton F. Post, Robert Michael Mckay, George S. Bullerjahn Feb 2016

Identification, Enumeration And Diversity Of Nitrifying Planktonic Archaea And Bacteria In Trophic End Members Of The Laurentian Great Lakes, Maitreyee Mukherjee, Anirban Ray, Anton F. Post, Robert Michael Mckay, George S. Bullerjahn

Great Lakes Institute for Environmental Research Publications

Oligotrophic Lake Superior and mesotrophic Lake Erie are trophic end members of the hydrologically connected Laurentian Great Lakes system, and as such exhibit different profiles of dissolved nitrogen species. Nitrification in Lake Superior has led to increasing nitrate concentrations over the past century, as opposed to Erie, where nitrate inventories have declined due to denitrification. In this study, we examined the abundance and diversity of nitrifying microbes involved in the oxidation of ammonia to nitrite, and nitrite to nitrate. By in situ hybridization methods, we enumerated the major planktonic ammonia oxidizing bacteria (AOB) and archaea (AOA) during a July 2011 …


Latitudinal Variation In Ecological Opportunity And Intraspecific Competition Indicates Differences In Niche Variability And Diet Specialization Of Arctic Marine Predators, David J. Yurkowski, Steven Ferguson, Emily S. Choy, Lisa L. Loseto, Tanya M. Brown, Derek Cg Muir, Christina Ad Semeniuk, Aaron T. Fisk Jan 2016

Latitudinal Variation In Ecological Opportunity And Intraspecific Competition Indicates Differences In Niche Variability And Diet Specialization Of Arctic Marine Predators, David J. Yurkowski, Steven Ferguson, Emily S. Choy, Lisa L. Loseto, Tanya M. Brown, Derek Cg Muir, Christina Ad Semeniuk, Aaron T. Fisk

Great Lakes Institute for Environmental Research Publications

Individual specialization (IS), where individuals within populations irrespective of age, sex, and body size are either specialized or generalized in terms of resource use, has implications on ecological niches and food web structure. Niche size and degree of IS of near-top trophic-level marine predators have been little studied in polar regions or with latitude. We quantified the largescale latitudinal variation of population- and individual-level niche size and IS in ringed seals (Pusa hispida) and beluga whales (Delphinapterus leucas) using stable carbon and nitrogen isotope analysis on 379 paired ringed seal liver and muscle samples and 124 paired beluga skin and …


Employing Individual Measures Of Baseline Glucocorticoids As Population-Level Conservation Biomarkers: Considering Within-Individual Variation In A Breeding Passerine, Christine L. Madliger, Oliver P. Love Jan 2016

Employing Individual Measures Of Baseline Glucocorticoids As Population-Level Conservation Biomarkers: Considering Within-Individual Variation In A Breeding Passerine, Christine L. Madliger, Oliver P. Love

Great Lakes Institute for Environmental Research Publications

Labile physiological variables, such as stress hormones [i.e. glucocorticoids (GCs)], allow individuals to react to perturbations in their environment and may therefore reflect the effect of disturbances or positive conservation initiatives in advance of population-level demographic measures. Although the application of GCs as conservation biomarkers has been of extensive interest, few studies have explicitly investigated whether baseline GC concentrations respond to disturbances consistently across individuals. However, confirmation of consistent responses is of paramount importance to assessing the ease of use of GCs in natural systems and to making valid interpretations regarding population-level change (or lack of change) in GC concentrations. …


Temporal Overlap And Repeatability Of Feather Corticosterone Levels: Practical Considerations For Use As A Biomarker, Christopher M. Harris, Christine L. Madliger, Oliver P. Love Jan 2016

Temporal Overlap And Repeatability Of Feather Corticosterone Levels: Practical Considerations For Use As A Biomarker, Christopher M. Harris, Christine L. Madliger, Oliver P. Love

Great Lakes Institute for Environmental Research Publications

The measurement of corticosterone (CORT) levels in feathers has recently become an appealing tool for the conservation toolbox, potentially providing a non-invasive, integrated measure of stress activity throughout the time of feather growth. However, because the mechanism of CORT deposition, storage and stability in feathers is not fully understood, it is unclear how reliable this measure may be, especially when there is an extended interval between growth and feather collection. We compared CORT levels of naturally grown feathers from tree swallows (Tachycineta bicolor) that were moulted and regrown concurrently and therefore expected to have similar CORT levels. Specifically, we compared …


Determination Of The Gut Retention Of Plastic Microbeads And Microfibers In Goldfish 1 (Carassius Auratus), Stefan Grigorakis, Sherri A. Mason, Ken G. Drouillard Jan 2016

Determination Of The Gut Retention Of Plastic Microbeads And Microfibers In Goldfish 1 (Carassius Auratus), Stefan Grigorakis, Sherri A. Mason, Ken G. Drouillard

Great Lakes Institute for Environmental Research Publications

Microplastics are ubiquitous pollutants in aquatic habitats and commonly found in the gut contents of fish yet relatively little is known about the retention of these particles by fish. In this study, goldfish were fed a commercial fish food pellet amended with 50 particles of one of two microplastics types, microbeads and microfibers. Microbeads were obtained from a commercial facial cleanser while microfibers were obtained from washed synthetic textile. Following consumption of the amended pellet, fish were allowed to feed to satiation on non-amended food followed by fasting for periods ranging from 1.5 h to 6 days. Fish sacrificed at …


Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. Mckay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Lesley V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen Jan 2016

Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. Mckay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Lesley V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen

Great Lakes Institute for Environmental Research Publications

In early August 2014, the municipality of Toledo, OH (USA) issued a ‘do not drink’ advisory on their water supply directly affecting over 400,000 residential customers and hundreds of businesses (Wilson, 2014). This order was attributable to levels of microcystin, a potent liver toxin, which rose to 2.5 μg L−1 in finished drinking water. The Toledo crisis afforded an opportunity to bring together scientists from around the world to share ideas regarding factors that contribute to bloom formation and toxigenicity, bloom and toxin detection as well as prevention and remediation of bloom events. These discussions took place at an NSF- …