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Ohio Sea Grant Research eNewsletter January 2019


Ohio Sea Grant Research eNewsletter January 2019


Twine Line Fall/Winter 2018

Twine Line Fall/Winter 2018

Results from an ongoing partnership between 10 Ohio universities continue to benefit the state and its residents. Read about some of the newest findings, as well as other Ohio Sea Grant and Stone Lab success stories, in this newest issue.

VOLUME: 40 ISSUE: 3 LENGTH: 19 pages
Twine Line

Harmful Algal Bloom Research Initiative Year 3 Report


The third-year report continues to show that the state of Ohio has benefited from the initiative.

Technical Bulletin

Harmful Algal Bloom Research Initiative Year 3 Report Executive Summary


Abridged version of the Harmful Algal Bloom Research Initiative Year 3 Report.

Technical Bulletin

Twine Line Spring/Summer 2018

Twine Line Spring/Summer 2018

Making Lake Erie Science Come Alive

Ohio Sea Grant celebrates its 40th anniversary with a special issue of Twine Line, packed with science, research and education stories from the past, present and future of the program.

VOLUME: 40 ISSUE: 2 LENGTH: 35 pages
Twine Line

Stone Lab Guest Lecture: ODNR Division of Wildlife


Research Brief
Invasive Species Management and Research: Are we working at the same scales?
Dr. Jonathan Bossenbroek, Professor of Ecology, The University of Toledo

Guest Lecture
Fish Management in the 21st Century
Rich Carter, Executive Administrator, Fish Management Group, Ohio Department of Natural Resources (ODNR) Division of Wildlife

DURATION: ~ 1 hr, 46 mins
Broadcast, Podcast, Webinar

Stone Lab REU Presentations 2018


Student Presenters

Trace Nutrient Limitation of Nitrogen Fixation of Dolichospermum in the Central Basin of Lake Erie 2015-2017
Alyssa Armstrong, Youngstown State University (Limnology REU)

Nutrient and Light Limitation of Benthic Cyanobacteria in Lake Erie
Jade Bolinger, Bowling Green State University (Limnology REU)

Predicting Lake Erie Algal Blooms based on Alternate Ecosystem States Theory: Early Warning Signals of an Impending Bloom
Allison Erf, Youngstown State University (Limnology REU)

How do algal and sedimentary turbidity affect the swimming performance of Emerald Shiner in Lake Erie?
Harrison Fried, The Ohio State University (Ichthyology REU)

Planktonic algal community composition of the Maumee River: environmental factors and their relation to toxin-producing cyanobacteria
Crista Kieley, University of New England (Limnology REU)

Using Avian Survivorship to Assess Habitat Quality of Lake Erie Island Preserves for Breeding Birds
Raphaella Mascia, College of the Holy Cross (Ornithology REU)

Forest and Soil Composition after Emerald Ash Borer and Invasive Tree Removal on Middle Bass Island
Matt Monteith, The Ohio State University (Botany REU)

DURATION: ~ 1 hr, 51 mins
Broadcast, Podcast, Webinar

Early onset of a microcystin-producing cyanobacterial bloom in and agriculturally-influenced Great Lakes tributary


In late May 2016, a cyanobacterial harmful algal bloom (cHAB) was detected in the Maumee River, the largest tributary to Lake Erie, the southernmost lake of the Laurentian Great Lakes system. Testing on 31 May identified Planktothrix agardhii as the dominant cyanobacterium with cell abundance exceeding 1.7×10 9 cells/L and total microcystins (MC) reaching 19 μg/L MC-LR equivalents, a level over 10-fold higher than the 2015 revised U.S. Environmental Protection Agency (EPA) national health advisory levels for drinking water exposure to adults. Low river discharge coincident with negligible precipitation through the latter half of May coincided with an 80% decline in river turbidity that likely favored bloom formation by a low-light adapted P. agardhii population. Also contributing to the cHAB were high initial nutrient loads and an increase of the river temperature from 13°C to 26°C over this same period. The bloom persisted through 5 June with microcystins exceeding 22 μg/L MC-LR equivalents at the bloom peak. By 6 June, the river had returned to its muddy character following a rain event and sampling on 7 June detected only low levels of toxin (<0.6 μg/L) at public water systems located near the bloom origin. The elevated toxin production associated with this early onset bloom was without precedent for the Maumee River and an unique attribute of the cHAB was the high proportion of potentially-toxic genotypes. Whereas Planktothrix spp. is common in lotic environments, and has been previously detected in the Maumee, blooms are not commonly reported. This early onset, microcystin-producing cHAB provided a rare opportunity to glean insights into environmental factors that promote bloom development and dominance by Planktothrix in lotic environments.

LENGTH: 13 pages
External Partner Publication

Nitrogen cycling in Sandusky Bay, Lake Erie: oscillations between strong and weak export and implications for harmful algal blooms


Recent global water quality crises point to an urgent need for greater understanding of cyanobacterial harmful algal blooms (cHABs) and their drivers. Nearshore areas of Lake Erie such as Sandusky Bay may become seasonally limited by nitrogen (N) and are characterized by distinct cHAB compositions (i.e., Planktothrix over Microcystis). This study investigated phytoplankton N uptake pathways, determined drivers of N depletion, and characterized the N budget in Sandusky Bay. Nitrate (NO3−) and ammonium (NH4+) uptake, N fixation, and N removal processes were quantified by stable isotopic approaches. Dissimilatory N reduction was a relatively modest N sink, with denitrification, anammox, and N2O production accounting for 84, 14, and 2% of sediment N removal, respectively. Phytoplankton assimilation was the dominant N uptake mechanism, and NO3− uptake rates were higher than NH4+ uptake rates. Riverine N loading was sometimes insufficient to meet assimilatory and dissimilatory demands, but N fixation alleviated this deficit. N fixation made up 23.7–85.4% of total phytoplankton N acquisition and indirectly supports Planktothrix blooms. However, N fixation rates were surprisingly uncorrelated with NO3− or NH4+ concentrations. Owing to temporal separation in sources and sinks of N to Lake Erie, Sandusky Bay oscillates between a conduit and a filter of downstream N loading to Lake Erie, delivering extensively recycled forms of N during periods of low export. Drowned river mouths such as Sandusky Bay are mediators of downstream N loading, but climate-change-induced increases in precipitation and N loading will likely intensify N export from these systems.

VOLUME: 15 LENGTH: 16 pages
External Partner Publication

Optimization of extraction methods for quantification of microcystin-LR and microcystin-RR in fish, vegetable, and soil matrices using UPLC–MS/MS


Human-driven environmental change has increased the occurrence of harmful cyanobacteria blooms in
aquatic ecosystems. Concomitantly, exposure to microcystin (MC), a cyanobacterial toxin that can
accumulate in animals, edible plants, and agricultural soils, has become a growing public health concern.
For accurate estimation of health risks and timely monitoring, availability of reliable detection methods is
imperative. Nonetheless, quantitative analysis of MCs in many types of biological and environmental
samples has proven challenging because matrix interferences can hinder sample preparation and extraction procedures, leading to poor MC recovery. Herein, controlled experiments were conducted to
enhance the use of ultra-performance liquid-chromatography tandem-mass spectrometry (UPLC–MS/
MS) to recover MC-LR and MC-RR at a range of concentrations in seafood (fish), vegetables (lettuce), and environmental (soil) matrices. Although these experiments offer insight into detailed technical aspects of the MC homogenization and extraction process (i.e., sonication duration and centrifugation speed during homogenization; elution solvent to use during the final extraction), they centered on identifying the best (1) solvent system to use during homogenization (2–3 tested per matrix) and (2) single-phase extraction (SPE) column type (3 tested) to use for the final extraction. The best procedure consisted of the following, regardless of sample type: centrifugation speed = 4200 xg; elution volume = 8 mL; elution solvent = 80% methanol; and SPE column type = hydrophilic–lipophilic balance (HLB), with carbon also being satisfactory for fish. For sonication, 2 min, 5 min, and 10 min were optimal for fish, lettuce, and soil matrices, respectively. Using the recommended HLB column, the solvent systems that led to the highest recovery of MCs were methanol:water:butanol for fish, methanol:water for lettuce, and EDTA-Na4P2O7
for soils. Given that the recommended procedures resulted in average MC-LR and MC-RR recoveries that
ranged 93 to 98%, their adoption for the preparation of samples with complex matrices before UPLC–MS/
MS analysis is encouraged.

VOLUME: 76 LENGTH: 10 pages
External Partner Publication

Twine Line Winter/Spring 2018

Twine Line Winter/Spring 2018

Twine Line Winter/Spring 2018. Twine Line gets ready for summer. Learn how travel benefits our state and the ways that research at Stone Lab is improving the quality of our drinking water, plus lots more in this issue of Twine Line.

VOLUME: 40 ISSUE: 1 LENGTH: 19 pages
Twine Line

Twine Line Fall/Winter 2017

Twine Line Fall/Winter 2017

All Washed Up – Ohio Sea Grant works to stop marine debris before it gets to Lake Erie beaches.

VOLUME: 39 ISSUE: 2 LENGTH: 19 pages
Twine Line

Intercomparison of Approaches to to the Empirical Line Method for Vicarious Hyperspectral Reflectance Calibration


Analysis of visible remote sensing data research requires removing atmospheric effects by conversion from radiance to at-surface reflectance. This conversion can be achieved through theoretical radiative transfer models, which yield good results when well-constrained by field observations, although these measurements are often lacking. Additionally, radiative transfer models often perform poorly in marine or lacustrine settings or when complex air masses with variable aerosols are present. The empirical line method (ELM) measures reference targets of known reflectance in the scene. ELM methods require minimal environmental observations and are conceptually simple. However, calibration coefficients are unique to the image containing the reflectance reference. Here we compare the conversion of hyperspectral radiance observations obtained with the NASA Glenn Research Center Hyperspectral Imager to at-surface reflectance factor using two reflectance reference targets. The first target employs spherical convex mirrors, deployed on the water surface to reflect ambient direct solar and hemispherical sky irradiance to the sensor. We calculate the mirror gain using near concurrent at-sensor reflectance, integrated mirror radiance, and in situ water reflectance. The second target is the Lambertian-like blacktop surface at Maumee Bay State Park, Oregon, OH, where reflectance was measured concurrently by a downward looking, spectroradiometer on the ground, the aerial hyperspectral imager and an upward looking spectroradiometer on the aircraft. These methods allows us to produce an independently calibrated at-surface water reflectance spectrum, when atmospheric conditions are consistent. We compare the mirror and blacktop-corrected spectra to the in situ water reflectance, and find good agreement between methods. The blacktop method can be applied to all scenes, while the mirror calibration method, based on direct observation of the light illuminating the scene validates the results. The two methods are complementary and a powerful evaluation of the quality of atmospheric correction over extended areas. We decompose the resulting spectra using varimax-rotated, principal component analysis, yielding information about the underlying color producing agents that contribute to the observed reflectance factor scene, identifying several spectrally and spatially distinct mixtures of algae, cyanobacteria, illite, haematite, and goethite. These results have implications for future hyperspectral remote sensing missions, such as PACE, HyspIRI, and GeoCAPE.

LENGTH: 20 pages

Stone Lab REU Presentations 2017


Stone Lab REU Presentations 2017

Depth distribution of phytoplankton in western Lake Erie: Correlation between buoy and Fluoroprobe-derived data
Alex Johnson, Cleveland State University

Visual detection thresholds of walleye under varying turbidity
Andrew Oppliger, The Ohio State University

Intoxicated fishes: evaluating Aqui-S as an anesthetic for lake trout
Kearstin Findley, Rockford University

Determining nutrient limitations of benthic algae growth using a nutrient diffusing substrate
Marissa Musk, Michigan State University

Nutrient limitations in the central basin of Lake Erie
Madeline Lambrix, The Ohio State University

Effects of sediment resuspension on nutrient flux and nitrification in Lake Erie
Taylor Michael, Kent State University

Changes in forest composition in lowland island forests after the emerald ash borer
Camille Manoukian, The Ohio State University

Importance of Lake Erie island preserves for birds during breeding season
Stacey Clay, The Ohio State University

DURATION: ~ 2 hrs, 16 mins
Broadcast, Podcast, Webinar

Harmful Algal Bloom Research: Ohio State's Dr. Justin Chaffin and Citizen Science


Stone Lab’s research coordinator, Dr. Justin Chaffin, explains the importance of citizen science performed by Lake Erie charter boat captains in monitoring the health of Lake Erie.

DURATION: 2 mins
Broadcast, Podcast, Webinar

Stone Lab REU Presentations 2016


Students from Stone Lab’s Research Experience for Undergraduates (REU) program share the results of their research.

DURATION: ~ 2 hrs, 40 mins
Broadcast, Podcast, Webinar

2016 Harmful Algal Bloom Forecast: Dr. Rick Stumpf and Dr. Laura Johnson


Drs. Rick Stumpf and Laura Johnson explain the forecast for harmful algal blooms (HABs) in Lake Erie for 2016.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

Twine Line Summer 2016

Twine Line Summer 2016

You’re never too young or too old to learn something new! This issue of Twine Line shows some of the different ways Stone Lab educates students of all ages, plus new research from the island. Only in this issue of Twine Line!

VOLUME: 38 ISSUE: 1 LENGTH: 19 pages
Twine Line

2016 Harmful Algal Bloom Forecast Preview: Ohio State's Dr. Conor Keitzer and Dr. Stuart Ludsin


Dr. Conor Keitzer and Dr. Stuart Ludsin of The Ohio State University discuss the Western Lake Erie Basin Conservation Effects Assessment Project research, which will be discussed during the 2016 Harmful Algal Bloom Forecast webinar at 2 p.m. July 7, 2016.

DURATION: 2 mins
Broadcast, Podcast, Webinar

2016 Harmful Algal Bloom Forecast Preview: Ohio State's Dr. Jay Martin


The Ohio State University’s Dr. Jay Martin talks about Ohio State research and phosphorus reduction, previewing topics he will discuss during the 2016 Harmful Algal Bloom Forecast webinar.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

Stone Lab Guest Lecture: Ohio EPA's legislative priorities and challenges


Research Brief
Microbial modification of natural and anthropogenic compounds in engineered systems
Paula Mouser, Assistant Professor, Department of Civil, Environmental and Geodetic Engineering, The Ohio State University

Guest Lecture
Ohio EPA’s legislative priorities and challenges
Laura Factor, Assistant Director, Ohio Environmental Protection Agency

DURATION: ~ 2 hrs, 13 mins
Broadcast, Podcast, Webinar

Stone Lab Student Spotlight: Jeffry Hayes

Broadcast, Podcast, Webinar

Ohio Sea Grant eNewsletter October 2015


Ohio Sea Grant eNewsletter October 2015


Stone Lab Guest Lecture: Ohio State Research in Review


Jay Martin breaks down impacts of phosphorus in the western Basin of Lake Erie and what needs to be done to help fix the problem.

Carolyn Whitacre, Vice President for Research at the Ohio State University explains how OSU facilitates research and provides research opportunities for its students.

DURATION: ~ 1 hr, 44 mins
Broadcast, Podcast, Webinar

Oxygen use by Nitrification in the Hypolimnion and Sediments of Lake Erie


Nitrification is an oxygen consumptive process, consuming 2 mol of oxygen permol of ammonium oxidized. Hypolimnion
and sediment sampleswere collected during the summers of 2008–2010 in Lake Erie to determine the
total oxygen consumption and oxygen consumption fromnitrification by blocking nitrification with selective inhibitors.
Oxygen consumption by nitrification in the hypolimnion was 3.7 ± 2.9 (mean ± 1 SD) μmol O2/L/d,
with nitrification accounting for 32.6 ± 22.1% of the total oxygen consumption. Nitrification in the hypolimnion
contributed more to oxygen consumption in the eastern sites than western sites and was lowest in September.
The nitrification rate did not correlatewith environmental factors such as oxygen, nitrate or ammonium, or nitrifier
numbers. Oxygen consumption by nitrification in sediment slurries was 7.1 ± 5.8 μmol O2/g/d, with nitrification
accounting for 27.0 ± 19.2% of the total oxygen consumption with the lowest rates in July and the lowest
percentages in June. Oxygen consumption by nitrification in intact sediment coreswas 682 ± 61.1 μmol O2/m/d
with nitrification accounting for 30.4 ± 10.7% of the total oxygen consumption. Nitrification rates in intact cores
were generally highest in September. The proportion of oxygen consumed by nitrification corresponds closely
with what would be predicted from complete oxidation of a Redfield molecule (23%).While nitrification is unlikely
to be the dominant oxygen consumptive process, the rates observed in Lake Eriewere sufficient to theoretically
deplete a large portion of the hypolimnetic oxygen pool during the stratified period.

VOLUME: 40 ISSUE: 1 LENGTH: 5 pages

Organic and inorganic nitrogen utilization by nitrogen-stressed cyanobacteria during bloom conditions


Manuscript on nitrogen utilization by cyanobacteria


Cyanobacterial blooms often occur in lakes that have high phosphorus (P) and low nitrogen (N) concentrations, and the growth rate of the blooms is often constrained by N. For these reasons, many researchers have suggested that regulation of both P and N is required to control eutrophication. However, because N occurs in many bioavailable forms, regulation of a particular form may be beneficial rather than regulation of all N forms. To address how N-stressed cyanobacteria respond to various N inputs, N enrichment experiments (nitrate, ammonium, urea, and alanine) were performed during N-limited cyanobacterial blooms in Maumee and Sandusky Bays of Lake Erie and in Grand Lake St. Marys (GLSM). Bioavailable N (nitrate, urea, and ammonium) concentrationswere also determined. Microcystis aeruginosa dominated the Maumee Bay bloom, where the highest growth rates were in response to ammonium additions, and lowest growth rates were in response to nitrate. Urea and the amino acid alanine resulted in intermediate growth rates. Planktothrix agardhii dominated the Sandusky Bay and GLSM blooms, where nitrate, ammonium, and urea addition resulted in similar growth rates. Additions of alanine did not stimulate growth of the Planktothrix blooms. Incubations using stable isotope 15N showed the cyanobacteria had a preference for ammonium, but the other forms were also assimilated in the presence of ammonium. These results show that cyanobacterial blooms will assimilate multiple forms of N to support growth. Thus, if lake managers do decide that N abatement is necessary, then all forms of bioavailable N need to be constrained.

DOI: 10.1007/s10811-013-0118-0 VOLUME: 26 ISSUE: 1 LENGTH: 10 pages

Length-Weight Relationships of the Mimic Shiner Notropis volucellua (Cope 1865) in the Western Basin of Lake Erie


Gender relationships between total and standard length (mm) were compared to weight (mg) in the mimic shiner,
Notropis volucellus for the western Lake Erie basin in the vicinity of the Bass Islands. Length and weight relationship (n=300),
length-frequency distribution, and sex ratios (n=884) from a single date from Gibraltar Island in June 2012 were analyzed for
coastal shoreline and tributaries. A strong positive correlation was found between length and weight for both males and females.
In females, a significant positive correlation exists between standard length (SL) and body weight (F=671.5, d.f.=135) and between
total length (TL) and body weight (F=681.4, d.f.=135). In males, there was also a strong positive correlation between SL and body
weight (F=1744.9, d.f.=160) and between TL and body weight (F=1656.6, d.f.=160). Combining data for the two sexes helped
determine a strong relationship between SL and body weight (F=1908.3, d.f.=299) and between TL and body weight (F=1885.9,
d.f.=299) that was consistent with the results from the individual sexes. The growth patterns of male and female mimic shiner
differed significantly for both SL (F=0.76, p>0.05, d.f.=159-134) and TL (F=0.76, p>0.05, d.f.=159-134). Age I females ranged
from 29–51 mm TL and Age I males ranged from 30–46 mm TL based on 884 individuals from Gibraltar Island. Age II females
ranged from 57–61 mm TL and Age II males ranged from 54–56 mm TL. Mimic shiner exhibit indeterminate growth and gender
influences growth patterns.

VOLUME: 112 ISSUE: 2 LENGTH: 6 pages

Research Overview: Holocene Development of Lake Erie


. This paper reviews and summarizes research on the Holocene evolutionary history of Lake Erie. New bathymetric data published in 1998 and more
recently by the National Geophysical Data Center reveal lake-fl oor features indicative of former, now inundated, shorelines. These data combined with other
recent research, permit a detailed reconstruction of Lake Erie’s complex history since the Wisconsinan ice sheet retreated some 12,000 years ago, ending a
series of glacial lakes and initiating a series of post-glacial lake stages. The lakes that have occupied the Lake Erie Basin are grouped into three phases. The
oldest phase, 14,400 to 12,000 years ago, had lake stages associated with glaciers in the basin and were higher than present Lake Erie. The middle phase,
12,000 to 4,700 years ago, had lake stages isolated from Upper Lakes drainage during a dryer climatic period and were below the present level of Lake Erie. In
the last phase, from 4,700 to present, the Lake Erie Basin received Upper Lakes drainage and the water level rose to a slightly higher stage before establishing
the present elevation through outlet erosion.

VOLUME: 112 ISSUE: 2 LENGTH: 13 pages

DNA Barcoding to Confirm Morphological Traits and Determine Relative Abundance of Burrowing Mayfly Species in Western Lake Erie


Burrowing mayfly species of the genus Hexagenia are well known indicators of environmental health in lakes and rivers. Two species, H. limbata and H. rigida, are indistinguishable as nymphs and as adult females. Our objectives were to develop a genetic technique to distinguish between the two species and identify morphological features that separate cryptic nymphs and adult females. Fifty nymphs were collected before emergence from 10 sites throughout the western basin of Lake Erie in 2004 and 2005. Using known specimens of adult aerial male H. limbata and H. rigida, we used the mitochondrial cytochrome c oxidase subunit 1 (COI) gene to identify a 16 base pair (bp) difference between species. DNA sequencing confirmed correct species identification based on differences in abdominal pigmentation patterns on adult female imagos in 19 of 20 cases; the lone exception was a female with very faint pigmentation. Pigmentation patterns between species were consistent on nymphs, subimagos and imagos of both sexes. Populations of both species are panmictic across the western basin of Lake Erie, but H. limbata is the numerically dominant species, representing 70 to 100% of nymphs at sites in both years. A separate lineage of H limbata was discovered in the samples. The ability to distinguish nymphs of the two species will aid in developing more sensitive ecosystem indicators.

DOI: 10.1016/j.jglr.2011.11.010 VOLUME: 38 ISSUE: 1 LENGTH: 6 pages

Philopatry and Vagrancy of White Bass (Morone chrysops) Spawning in the Sandusky River: Evidence of Metapopulation Structure in Western Lake Erie Using Otolith Chemistry


Although natal homing and philopatry are well studied in anadromous salmon, few studies have investigated philopatric behavior in large, freshwater systems. In western Lake Erie, white bass (Morone chrysops) undergo seasonal spawning migrations from the open-water regions of Lake Erie to nearshore reef complexes and tributaries. The three primary spawning locations in Lake Erie are within 80 km of each other and are not separated by physical barriers. We used naturally occurring differences in otolith strontium concentrations among major spawning locations to address philopatry and vagrancy to the Sandusky River spawning location. Most individuals spawning in the Sandusky River were natal to this river (73%). No statistically significant differences in the extent of homing by sex or age of spawning were found, although a potential pattern of decreased homing with increased age of fish was observed. Given the proportion of vagrant individuals we found spawning in the Sandusky River (27%), it is unlikely that Lake Erie white bass spawning populations are genetically distinct. Furthermore, the white bass population in Lake Erie appears to be structured as a metapopulation, with non-philopatric individuals serving as a link between spawning populations.

DOI: 10.1016/j.jglr.2011.08.012 VOLUME: 37 ISSUE: 4 LENGTH: 6 pages

Expansion of Tubenose Gobies Proterorhinus semilunaris into Western Lake Erie and Potential Effects on Native Species


The Eurasian freshwater tubenose goby Proterorhinus semilunaris (formerly Proterorhinus marmoratus) invaded the Laurentian Great Lakes in the 1990s, presumably via ballast water from transoceanic cargo ships. Tubenose gobies spread throughout Lake St. Clair, its tributaries, and the Detroit River system, and also are present in the Duluth-Superior harbor of Lake Superior. Using seines and bottom trawls, we collected 113 tubenose gobies between July 2007 and August 2009 at several locations in western Lake Erie. The number and range of sizes of specimens collected suggest that that tubenose gobies have become established and self-sustaining in the western basin of Lake Erie. Tubenose gobies reached maximum densities in sheltered areas with abundant macrophyte growth, which also is their common habitat in native northern Black Sea populations. The diet of tubenose gobies was almost exclusively invertebrates, suggesting dietary overlap with other benthic fishes, such as darters (Etheostoma spp. and Percina sp.), madtoms (Noturus spp.), and sculpins (Cottus spp.). A single mitochondrial DNA haplotype was identified, which is the most common haplotype found in the original colonization area in the Lake St. Clair region, suggesting a founder effect. Tubenose gobies, like round gobies Neogobius melanostomus, have early life stages that drift owing to vertical migration, which probably allowed them to spread from areas of colonization. The Lake St. Clair-Lake Erie corridor appears to have served as an avenue for them to spread to the western basin of Lake Erie, and abundance of shallow macrophyte-rich habitats may be a key factor facilitating their further expansion within Lake Erie and the remainder of the Laurentian Great Lakes.

DOI: 10.1007/s10530-011-9962-5 VOLUME: 13 ISSUE: 12 LENGTH: 9 pages

The Effects of Dreissenid Mussels on the Survival and Condition of Burrowing Mayflies (Hexagenia spp.) in Western Lake Erie


Burrowing mayflies (Hexagenia limbata and H. rigida) are once again prominent members of the benthic community in western Lake Erie. However, this community is now dominated by dreissenid mussels. We conducted a laboratory experiment and field sampling to investigate whether survival and condition of Hexagenia were affected by the presence, density, and quality of dreissenid mussels. In a laboratory experiment, Hexagenia survival was higher in microcosms without dreissenid mussels. We also found Hexagenia density to be higher at field sites with low dreissenid density, suggesting that Hexagenia survival is higher in these areas as well. In microcosm treatments with low dreissenid density, Hexagenia survival was higher in treatments with live dreissenids than in treatments containing only dreissenid shells. These findings suggest that while dreissenid shells degrade the quality of soft sediments for Hexagenia, some of the negative effect is offset by the presence of live dreissenids. The positive effect of live dreissenids is likely due to additional food resources made available to Hexagenia by the filtering activity of dreissenids. Neither dreissenid density nor shell “type” (shells alone or live dreissenids in shells) had an effect on Hexagenia condition. Thus, the interactions between these dominant benthic invertebrates are complex. Recovery of Hexagenia populations in western Lake Erie is likely affected by both changing environmental conditions due to anthropogenic activities and the introduction of exotic species into the benthic community. The results are likely to be continued instability of the benthic food web and unpredictable consequences for human utilization of this ecosystem.

DOI: doi:10.1016/j.jglr.2011.04.006 VOLUME: 37 ISSUE: 3 LENGTH: 5 pages

Identifying Relationships between Catches of Spawning Condition Yellow Perch and Environmental Variables in the Western Basin of Lake Erie


Although the reproductive behavior of yellow perch Perca
flavescens has been well documented in small systems, relatively
little is known about the spawning preferences of yellow perch in
large systems, such as the Laurentian Great Lakes. During 2006
and 2007, we compared the presence and abundance adult yellow
perch during the spring spawning season with environmental
variables in the western basin of Lake Erie. We also estimated the
timing of yellow perch spawning by comparing the relative abundance
of gravid and spent females collected in our trawls and then
comparing the proportion of gravid females with environmental
conditions at our sampling sites. Overall, the probability of catching
adult yellow perch and the catch per unit effort increased with
increasing bottom temperatures in the spring, whereas the probability
of catching gravid females increased with increasing Secchi
depth. However, the relationships between our catch metrics and
environmental variables were not consistent across years, possibly
as a result of the very strong 2003 year-class, which became
first-year spawners in 2006.We also documented that yellow perch
spawning occurred when bottom temperatures were between 11◦C
and 15◦C in the western basin; these temperatures were reached
on different dates in different parts of the basin and in different years. Thus, we suggest that management agencies consider basing
the start of the commercial fishing season on prevailing bottom
temperatures rather than using a set date across years and sites.

DOI: 10.1080/00028487.2011.545018 VOLUME: 140 ISSUE: 1 LENGTH: 5 pages

Lake Erie Nutrient Loading and Harmful Algal Blooms: Research Findings and Management Implications

LENGTH: 16 pages
Technical Summary

Summer and Winter Spatial Habitat Use by the Lake Erie Watersnake


In an effort to provide information to guide habitat management for the Lake Erie watersnake Nerodia sipedon
insularum, a federally threatened and Ohio state endangered species, we used radiotelemetry to obtain spatial habitat
data for adult snakes during the summer active season and during winter hibernation. During the summer active
season, terrestrial habitat use was limited to a narrow band of shoreline. Among individuals, maximum distance inland
from shore ranged from 1 to 50 m (mean = 8 m) and linear extent of shoreline ranged from 30 to 1,360 m (mean =
261 m). Winter hibernation occurred at varying distances inland with individual hibernation sites ranging from 1 to
580 m (mean = 29 m) from shore. Habitat use did not differ between males and females. Existing U.S. Fish and Wildlife
Service habitat management guidelines suggest that ground-disturbing activities within potential hibernation areas
(defined as terrestrial habitat within 161 m of shore) should be avoided in winter to prevent harm to hibernating
snakes. They suggest further that excavation and removal of shrubs, standing or downed trees, root masses, animal
burrows, piled rocks, cliffs, or bedrock within 21 m of shore should be avoided in summer to prevent harm to active
snakes. Given that Lake Erie watersnakes have recovered to the point where delisting is being proposed, these habitat
guidelines appear to be sufficient. However, maintaining voluntary compliance with habitat guidelines and meeting
the need for continued public outreach will be vital to ensure long-term persistence.

DOI: 10.3996/052010-JFWM-013 VOLUME: 1 ISSUE: 2 LENGTH: 8 pages

Oxyradical scavenging capacity by the S9 fraction of Hexagenia Spp. Nymphs From the Western Basin of Lake Erie: Neutralisation of Three Potent Oxidants


Oxidative stress is a general response of aquatic organisms to environmental contamination. Metals and organic compounds capable of redox cycling cause proliferation of reactive oxygen species (ROS) within organisms. Harm results from ROS-mediated DNA damage, lipid peroxidation, enzyme degradation and compromised intermediary metabolism. Variations in concentrations or activities of antioxidants have been proposed as biomarkers of toxicant-mediated oxidative stress in aquatic organisms. The total oxyradical scavenging capacity (TOSC) assay provides an index of biological resistance to ROS. Burrowing mayflies (Hexagenia spp.) are key indicator species of the health of numerous water bodies, including Lake Erie. TOSC has been used to evaluate the ROS scavenging capacity of tissues from a number of marine and freshwater invertebrates. This is the first study to evaluate ROS scavenging capacity in Hexagenia nymphs. Hexagenia nymphal tissue was homogenised in TRIS buffer containing a protease inhibitor cocktail and then differentially centrifuged to obtain a 9000 g supernatant (S9). The specific TOSC values (±SD, n=3) per μg protein are 2.08±0.43 for peroxyl radicals, 3.06±0.19 for hydroxyl radicals and 0.36±0.02 for peroxynitrite (n=3 to 4 determinations). These values for peroxyl radical scavenging capacity were equivalent to 11.9% and 77.0% that of Trolox (a water soluble analogue of vitamin E) and reduced glutathione TOSC equivalents, respectively, on a per μg basis. These results show that Hexagenia nymphal S9 is capable of neutralising peroxyl radicals and hydroxyl radicals effectively, but neutralises peroxynitrite considerably more weakly. The efficacy of this parameter as a biomarker of exposure to or effect of environmental contaminants will require controlled exposure analysis.

DOI: 10.1080/02757541003643495 VOLUME: 26 ISSUE: 2 LENGTH: 9 pages

Transient Social–Ecological Stability: the Effects of Invasive Species and Ecosystem Restoration on Nutrient Management Compromise in Lake Erie


Together, lake ecosystems and local human activity form complex social–ecological systems (SESs) characterized by feedback loops and discontinuous change. Researchers in diverse fields have suggested that complex systems do not have single stable equilibria in the long term because of inevitable perturbation. During this study, we sought to address the general question of whether or not stable social–ecological equilibria exist in highly stressed and managed lacustrine systems. Using an integrated human–biophysical model, we investigated the impacts of a species invasion and ecosystem restoration on SES equilibrium, defined here as a compromise in phosphorus management among opposing stakeholders, in western Lake Erie. Our integrated model is composed of a calibrated ecological submodel representing Sandusky Bay, and a phosphorus management submodel that reflects the societal benefits and costs of phosphorus regulation. These two submodels together form a dynamic feedback loop that includes freshwater ecology, ecosystem services, and phosphorus management. We found that the invasion of dreissenid mussels decreased ecosystem resistance to eutrophication, necessitating increased phosphorus management to preserve ecosystem services and thus creating the potential for a shift in social–ecological equilibrium. Additionally, our results suggest that net benefits in the region following the invasion of dreissenids may never again reach the pre-invasion level if on-site phosphorus control is the sole management lever. Further demonstrating transient system stability, large-scale wetland restoration shifted points of management compromise to states characterized by less on-site phosphorus management and higher environmental quality, resulting in a significant increase in net benefits in the region. We conclude that lacustrine SESs are open and dynamic, and we recommend that future models of these systems emphasize site-specific perturbation over equilibrium, thereby aiding the development of management plans for building system resistance to undesirable change that are both flexible and sustainable in an unknowable future.

VOLUME: 15 ISSUE: 1 LENGTH: 28 pages

Celebrating 30 Years of Ohio Sea Grant (Revision)

LENGTH: 8 pages

Celebrating 30 Years of Ohio Sea Grant


Brochure describing the accomplishments and impacts of Ohio Sea Grant over its first 30 years.

LENGTH: 8 pages

Great Lakes Regional Research Information Network Ad

LENGTH: 2 pages
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