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Drafts by Brent Murry

Research paper thumbnail of An Analytical Framework for Conservation Design at Landscape‐Scales (Landscape Conservation Design)

Landscape Conservation Design (LCD) is an integrated, collaborative, and holistic process [to des... more Landscape Conservation Design (LCD) is an integrated, collaborative, and holistic process [to design] and a product [a design] that achieves partners’ missions, mandates, and goals while ensuring sustainability of ecosystem services for current and future generations of Americans. The process results in a science‐based, technologically-advanced, spatially‐explicit product that identifies targets of interest to partners, articulates measurable objectives; assesses current and projected landscape patterns and processes; and identifies a desired future condition, conservation/development trade‐offs, and implementation strategies. When delivered in a coordinated fashion, strategies derived from landscape conservation design processes can meet both societal values and needs while maintaining ecological integrity and biodiversity. This paper describes the goals, objectives, and products associated with each phase of the LCD framework.

Papers by Brent Murry

Research paper thumbnail of Sex Role Differentiation in Brood Defense by a Nicaraguan Cichlid Fish, Amphilophus xiloanensis

Caribbean Journal of Science, 2008

Brood defense behaviour of parental Midas cichlids, Amphilophus xiloaensis, was observed in Lake ... more Brood defense behaviour of parental Midas cichlids, Amphilophus xiloaensis, was observed in Lake Xiloá, Nicaragua. The research was conducted during two study periods separated by 22 years, 1972-73 and 1995. Role-differentiation was observed between the male and female during brood defense. The male defended the territory from adult conspecifics, while the female defended the brood from predators. These observations were consistent in two different study periods 22 years apart and at two different locations within the lake. Attack rates increased as the brood matured, contradicting laboratory findings on this species. These findings reinforced the use of brood defense behavior as a possible diagnostic tool to differentiate sibling species. The pattern of brood care and role differentiation remained stable over many generations, and should be a useful character for distinguishing sibling species.

Research paper thumbnail of Species turnover drives β-diversity patterns across multiple spatial and temporal scales in Great Lake Coastal Wetland Communities

Research paper thumbnail of Effects of dreissenid mussels, chironomids, fishes, and zooplankton on growth of round goby in experimental aquaria

Http Dx Doi Org 10 1080 02705060 2011 553987, Jun 1, 2011

There is a widely accepted paradigm supported by early field and laboratory observations that the... more There is a widely accepted paradigm supported by early field and laboratory observations that the adult round goby (Neogobius melanostomus) is highly adapted to, and primarily survives on, dreissenid mussels. However, more recent stable isotope and diet analyses indicate that the round goby may not rely on dreissenid prey to the extent that was previously believed. We conducted a feeding

Research paper thumbnail of Characterizing Changes in Energy Pathways Leading to Smallmouth Bass and Rock Bass Resulting From the Round Goby Invasion of Great Lakes Tributaries

Research paper thumbnail of Water-level regulation and coastal wetland vegetation in the upper St. Lawrence River: inferences from historical aerial imagery, seed banks, and Typha dynamics

Hydrobiologia, 2010

... KS Godwin Department of Biology, Coastal Carolina University, PO Box 261954, Conway, SC 29528... more ... KS Godwin Department of Biology, Coastal Carolina University, PO Box 261954, Conway, SC 29528-6054, USA ... regres-sion and correlation analyses between three Lake Ontario stations (Lake): Rochester (1970–2002), Oswego (1970–2002), and Cape Vincent (1970– 2002 ...

Research paper thumbnail of The Influence of Trophic Guild Composition On the Body Size Distributions and Trophic Structure of Mid-Order River Fish Communities

Research paper thumbnail of Feeding Strategies and Diets of Young-of-the-Year Muskellunge from Two Large River Ecosystems

North American Journal of Fisheries Management, 2012

We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy samp... more We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy sampled in New York waters of the St. Lawrence and upper Niagara rivers to (1) describe diets and document use of nonnative prey, (2) examine the feeding strategy (generalized versus specialized) and the importance of different prey types, (3) evaluate temporal patterns in feeding strategy and prey importance, and

Research paper thumbnail of Lake Huron Beach Community Historical Comparison and Habitat Assessment

Lake Huron has undergone dramatic shifts in fish community composition as a result of invasive sp... more Lake Huron has undergone dramatic shifts in fish community composition as a result of invasive species introductions and food web changes. In particular, zebra mussels and round gobies have greatly impacted near-shore fish communities. Our objective was to assess near-shore fish communities of western Lake Huron and compare species composition post invasion to species composition in 1993, prior to the invasion of zebra mussels and round gobies. Beach fish communities were sampled by nighttime beach seining during spring and summer 2012. In addition, we compared species composition between rocky and sandy beach habitats using minnow traps and modified fyke nets in fall 2012. Species abundance has declined since the pre-invasion period, and species composition has shifted from an alewife and smelt dominated community to a round goby and minnow dominated community. Spotfin shiners, emerald shiners, and sand shiners were found at sites with predominantly sandy substrate. The observed sh...

Research paper thumbnail of Lake Huron Food Web Shifts After Multiple Invasions

Invasive species have had a global impact on aquatic systems. Over one hundred invasive species h... more Invasive species have had a global impact on aquatic systems. Over one hundred invasive species have invaded the Great Lakes over the last several decades after construction of the Erie Canal and the St. Lawrence Seaway. We are examining the impact of multiple invasion events on food web dynamics of northern Lake Huron using stable isotopes. We are using archived scales and spines from walleye Sander vitreus, brown trout Salmo trutta, and lake trout Salvelinus namaycush to quantify changes in energy source (δ13C) and trophic position (δ15N) dynamics before, during, and after the invasions in Lake Huron. Stable isotope analyses suggest that the invasive Hemimysis anomala and rusty crayfish Orconectes rusticus appear to form the base of the food web distinct from the zebra mussel Dreissena polymorpha in Thunder Bay. The invasive round goby Neogobius melanostomus appear to occupy the next higher trophic position, with strong overlap with several native forage fish (e.g., yellow perch P...

Research paper thumbnail of Influence of invasive species and oligotrophication on the size-structure and emergent food web properties of a large river fish assemblage

Background/Question/Methods Aquatic food webs are highly size-structured owing to metabolic scali... more Background/Question/Methods Aquatic food webs are highly size-structured owing to metabolic scaling, competition for limited resources, and trophic transfer energy losses. Resource availability, transfer efficiency, and metabolic scaling collectively have a strong influence on food web carrying capacity and stability. Food web size-structure, stability, carrying capacity, and transfer efficiency are important emergent food web properties. Size-spectra, log abundance (or normalized biomass) regressed against log body size, are an effective approach for assessing food web stability and functioning. Size-spectra integrate bottom-up and top-down processes and are fundamentally based on the well established allometric relationships between body size, metabolism, and abundance. Size-spectra greatly simplify complex food web dynamics and provide metrics of community capacity and ecological efficiency. Size-spectra have also been used as indices of food web health and have been shown to res...

Research paper thumbnail of Relationships between habitat characteristics and round goby abundance in Lakes Michigan and Huron

Journal of Great Lakes Research, 2015

Research paper thumbnail of Fish community size structure of small lakes: the role of lake size, biodiversity and disturbance

Journal of Freshwater Ecology, 2015

ABSTRACT Aquatic community body size distributions are highly predictable with decreasing abundan... more ABSTRACT Aquatic community body size distributions are highly predictable with decreasing abundance and increasing body size. This basic relationship has led to significant increases in our understanding of the internal regulation processes of aquatic communities. However, most of our understanding of the patterns of community size structure is derived from large aquatic systems with little known about the dynamics of small lakes. Processes that promote predictable, or deterministic, community size structure likely differ with levels of biodiversity and disturbance patterns, both of which frequently co-vary with ecosystem size. Here we examine the influence of lake size, fish species richness, and natural disturbance regime on fish community size structure in six small lakes (

Research paper thumbnail of Shift in a Large River Fish Assemblage: Body-Size and Trophic Structure Dynamics

PLOS ONE, 2015

As the intensity and speed of environmental change increase at both local and global scales it is... more As the intensity and speed of environmental change increase at both local and global scales it is imperative that we gain a better understanding of the ecological implications of community shifts. While there has been substantial progress toward understanding the drivers and subsequent responses of community change (e.g. lake trophic state), the ecological impacts of food web changes are far less understood. We analyzed Wabash River fish assemblage data collected from 1974-2008, to evaluate temporal variation in body-size structure and functional group composition. Two parameters derived from annual community sizespectra were our major response variables: (1) the regression slope is an index of ecological efficiency and predator-prey biomass ratios, and (2) spectral elevation (regression midpoint height) is a proxy for food web capacity. We detected a large assemblage shift, over at least a seven year period, defined by dramatic changes in abundance (measured as catchper-unit-effort) of the dominant functional feeding groups among two time periods; from an assemblage dominated by planktivore-omnivores to benthic invertivores. There was a concurrent increase in ecological efficiency (slopes increased over time) following the shift associated with an increase in large-bodied low trophic level fish. Food web capacity remained relatively stable with no clear temporal trends. Thus, increased ecological efficiency occurred simultaneous to a compensatory response that shifted biomass among functional feeding groups.

Research paper thumbnail of Application and transferability of Great Lakes coastal wetland indices of biotic integrity to high quality inland lakes of Beaver Island in northern Lake Michigan

and regulatory agencies to categorize the condition of a given ecosystem. IBIs are more widely us... more and regulatory agencies to categorize the condition of a given ecosystem. IBIs are more widely used in lotic systems and those that can be used over wide geographic regions or multiple systems are deemed most valuable. Lacustrine wetlands have intrinsic complexity and multidimensionality making them very difficult to classify. This, in turn, greatly affects the transferability of indices created for explicit regions and wetland types. Similarly, due to scarcity, relatively pristine reference conditions are seldom included in IBI calibration and represent a critical end of the disturbance continuum.

Research paper thumbnail of Impacts of Agricultural Drainage Outlets on Great Lakes Coastal Wetlands

Research paper thumbnail of Lakewide Estimates of Alewife Biomass and Chinook Salmon Abundance and Consumption in Lake Ontario, 1989–2005: Implications for Prey Fish Sustainability

Transactions of the American Fisheries Society, 2010

Stocking levels of Chinook salmon Oncorhynchus tshawytscha for Lake Ontario have been highly cont... more Stocking levels of Chinook salmon Oncorhynchus tshawytscha for Lake Ontario have been highly controversial since the early 1990s, largely because of uncertainties about lakewide abundance and rates of prey consumption. Previous estimates have focused on years before 1995; since then, however, the Lake Ontario ecosystem has undergone substantial changes, and there is new evidence of extensive natural recruitment. Presented here are new abundance estimates of Chinook salmon and alewives Alosa pseudoharengus in Lake Ontario and a reevaluation of the potential risk of alewife population collapse. We found that Lake Ontario has been supporting, on average (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), 1.83 3 10 6 (range, 1.08 3 10 6 to 3.24 3 10 6 ) Chinook salmon of ages 1-4, amounting to a mean annual biomass of 11.33 3 10 3 metric tons (range, 5.83 3 10 3 to 23.04 3 10 3 metric tons). During the same period (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), the lake supported an alewife biomass of 173.66 3 10 3 metric tons (range, 62.37 3 10 3 to 345.49 3 10 3 metric tons); Chinook salmon of ages 1-4 consumed, on average, 22% (range, 11-44%) of the alewife biomass annually. Because our estimates probably underestimate total consumption and because Chinook salmon are only one of several salmonine species that depend on alewives, predation pressure on the Lake Ontario alewife population may be high enough to raise concerns about long-term stability of this predator-prey system.

Research paper thumbnail of Feeding Strategies and Diets of Young-of-the-Year Muskellunge from Two Large River Ecosystems

North American Journal of Fisheries Management, 2012

We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy samp... more We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy sampled in New York waters of the St. Lawrence and upper Niagara rivers to (1) describe diets and document use of nonnative prey, (2) examine the feeding strategy (generalized versus specialized) and the importance of different prey types, (3) evaluate temporal patterns in feeding strategy and prey importance, and

Research paper thumbnail of Assessment of remnant unionid assemblages in a selection of Great Lakes coastal wetlands

Journal of Great Lakes Research, 2013

Research paper thumbnail of Use of wetland versus open habitats by round gobies in lakes Michigan and Huron: Patterns of CPUE, length, and maturity

Journal of Great Lakes Research, 2012

ABSTRACT It has been suggested that some Great Lakes coastal wetlands may be resistant to invasio... more ABSTRACT It has been suggested that some Great Lakes coastal wetlands may be resistant to invasion by several non-indigenous species including round goby, Neogobius melanostomus. However, there is inconclusive evidence regarding how susceptible exposed fringing coastal wetlands, in particular, are to round goby invasion. Therefore, we quantified round goby catch per unit effort (CPUE) using fyke nets in the Beaver Archipelago of Lake Michigan, and the Les Cheneaux islands and Saginaw Bay regions of Lake Huron. In addition, we examined the influence of body size and maturity on round goby habitat use. Catch per unit effort from fyke nets was highest in the Beaver Archipelago, where wetlands were dominated by small, immature round gobies and open water habitats were dominated by large adults. Fyke net catches within Les Cheneaux sites were similar between habitats and differences in size and maturity were not observed. Conversely, very few round goby were captured in wetlands of Saginaw Bay where CPUE was moderate in open water. This indicates that some exposed fringing wetlands in the Great Lakes, specifically those with high productivity, could have a higher degree of resistance to round goby invasion.

Research paper thumbnail of An Analytical Framework for Conservation Design at Landscape‐Scales (Landscape Conservation Design)

Landscape Conservation Design (LCD) is an integrated, collaborative, and holistic process [to des... more Landscape Conservation Design (LCD) is an integrated, collaborative, and holistic process [to design] and a product [a design] that achieves partners’ missions, mandates, and goals while ensuring sustainability of ecosystem services for current and future generations of Americans. The process results in a science‐based, technologically-advanced, spatially‐explicit product that identifies targets of interest to partners, articulates measurable objectives; assesses current and projected landscape patterns and processes; and identifies a desired future condition, conservation/development trade‐offs, and implementation strategies. When delivered in a coordinated fashion, strategies derived from landscape conservation design processes can meet both societal values and needs while maintaining ecological integrity and biodiversity. This paper describes the goals, objectives, and products associated with each phase of the LCD framework.

Research paper thumbnail of Sex Role Differentiation in Brood Defense by a Nicaraguan Cichlid Fish, Amphilophus xiloanensis

Caribbean Journal of Science, 2008

Brood defense behaviour of parental Midas cichlids, Amphilophus xiloaensis, was observed in Lake ... more Brood defense behaviour of parental Midas cichlids, Amphilophus xiloaensis, was observed in Lake Xiloá, Nicaragua. The research was conducted during two study periods separated by 22 years, 1972-73 and 1995. Role-differentiation was observed between the male and female during brood defense. The male defended the territory from adult conspecifics, while the female defended the brood from predators. These observations were consistent in two different study periods 22 years apart and at two different locations within the lake. Attack rates increased as the brood matured, contradicting laboratory findings on this species. These findings reinforced the use of brood defense behavior as a possible diagnostic tool to differentiate sibling species. The pattern of brood care and role differentiation remained stable over many generations, and should be a useful character for distinguishing sibling species.

Research paper thumbnail of Species turnover drives β-diversity patterns across multiple spatial and temporal scales in Great Lake Coastal Wetland Communities

Research paper thumbnail of Effects of dreissenid mussels, chironomids, fishes, and zooplankton on growth of round goby in experimental aquaria

Http Dx Doi Org 10 1080 02705060 2011 553987, Jun 1, 2011

There is a widely accepted paradigm supported by early field and laboratory observations that the... more There is a widely accepted paradigm supported by early field and laboratory observations that the adult round goby (Neogobius melanostomus) is highly adapted to, and primarily survives on, dreissenid mussels. However, more recent stable isotope and diet analyses indicate that the round goby may not rely on dreissenid prey to the extent that was previously believed. We conducted a feeding

Research paper thumbnail of Characterizing Changes in Energy Pathways Leading to Smallmouth Bass and Rock Bass Resulting From the Round Goby Invasion of Great Lakes Tributaries

Research paper thumbnail of Water-level regulation and coastal wetland vegetation in the upper St. Lawrence River: inferences from historical aerial imagery, seed banks, and Typha dynamics

Hydrobiologia, 2010

... KS Godwin Department of Biology, Coastal Carolina University, PO Box 261954, Conway, SC 29528... more ... KS Godwin Department of Biology, Coastal Carolina University, PO Box 261954, Conway, SC 29528-6054, USA ... regres-sion and correlation analyses between three Lake Ontario stations (Lake): Rochester (1970–2002), Oswego (1970–2002), and Cape Vincent (1970– 2002 ...

Research paper thumbnail of The Influence of Trophic Guild Composition On the Body Size Distributions and Trophic Structure of Mid-Order River Fish Communities

Research paper thumbnail of Feeding Strategies and Diets of Young-of-the-Year Muskellunge from Two Large River Ecosystems

North American Journal of Fisheries Management, 2012

We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy samp... more We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy sampled in New York waters of the St. Lawrence and upper Niagara rivers to (1) describe diets and document use of nonnative prey, (2) examine the feeding strategy (generalized versus specialized) and the importance of different prey types, (3) evaluate temporal patterns in feeding strategy and prey importance, and

Research paper thumbnail of Lake Huron Beach Community Historical Comparison and Habitat Assessment

Lake Huron has undergone dramatic shifts in fish community composition as a result of invasive sp... more Lake Huron has undergone dramatic shifts in fish community composition as a result of invasive species introductions and food web changes. In particular, zebra mussels and round gobies have greatly impacted near-shore fish communities. Our objective was to assess near-shore fish communities of western Lake Huron and compare species composition post invasion to species composition in 1993, prior to the invasion of zebra mussels and round gobies. Beach fish communities were sampled by nighttime beach seining during spring and summer 2012. In addition, we compared species composition between rocky and sandy beach habitats using minnow traps and modified fyke nets in fall 2012. Species abundance has declined since the pre-invasion period, and species composition has shifted from an alewife and smelt dominated community to a round goby and minnow dominated community. Spotfin shiners, emerald shiners, and sand shiners were found at sites with predominantly sandy substrate. The observed sh...

Research paper thumbnail of Lake Huron Food Web Shifts After Multiple Invasions

Invasive species have had a global impact on aquatic systems. Over one hundred invasive species h... more Invasive species have had a global impact on aquatic systems. Over one hundred invasive species have invaded the Great Lakes over the last several decades after construction of the Erie Canal and the St. Lawrence Seaway. We are examining the impact of multiple invasion events on food web dynamics of northern Lake Huron using stable isotopes. We are using archived scales and spines from walleye Sander vitreus, brown trout Salmo trutta, and lake trout Salvelinus namaycush to quantify changes in energy source (δ13C) and trophic position (δ15N) dynamics before, during, and after the invasions in Lake Huron. Stable isotope analyses suggest that the invasive Hemimysis anomala and rusty crayfish Orconectes rusticus appear to form the base of the food web distinct from the zebra mussel Dreissena polymorpha in Thunder Bay. The invasive round goby Neogobius melanostomus appear to occupy the next higher trophic position, with strong overlap with several native forage fish (e.g., yellow perch P...

Research paper thumbnail of Influence of invasive species and oligotrophication on the size-structure and emergent food web properties of a large river fish assemblage

Background/Question/Methods Aquatic food webs are highly size-structured owing to metabolic scali... more Background/Question/Methods Aquatic food webs are highly size-structured owing to metabolic scaling, competition for limited resources, and trophic transfer energy losses. Resource availability, transfer efficiency, and metabolic scaling collectively have a strong influence on food web carrying capacity and stability. Food web size-structure, stability, carrying capacity, and transfer efficiency are important emergent food web properties. Size-spectra, log abundance (or normalized biomass) regressed against log body size, are an effective approach for assessing food web stability and functioning. Size-spectra integrate bottom-up and top-down processes and are fundamentally based on the well established allometric relationships between body size, metabolism, and abundance. Size-spectra greatly simplify complex food web dynamics and provide metrics of community capacity and ecological efficiency. Size-spectra have also been used as indices of food web health and have been shown to res...

Research paper thumbnail of Relationships between habitat characteristics and round goby abundance in Lakes Michigan and Huron

Journal of Great Lakes Research, 2015

Research paper thumbnail of Fish community size structure of small lakes: the role of lake size, biodiversity and disturbance

Journal of Freshwater Ecology, 2015

ABSTRACT Aquatic community body size distributions are highly predictable with decreasing abundan... more ABSTRACT Aquatic community body size distributions are highly predictable with decreasing abundance and increasing body size. This basic relationship has led to significant increases in our understanding of the internal regulation processes of aquatic communities. However, most of our understanding of the patterns of community size structure is derived from large aquatic systems with little known about the dynamics of small lakes. Processes that promote predictable, or deterministic, community size structure likely differ with levels of biodiversity and disturbance patterns, both of which frequently co-vary with ecosystem size. Here we examine the influence of lake size, fish species richness, and natural disturbance regime on fish community size structure in six small lakes (

Research paper thumbnail of Shift in a Large River Fish Assemblage: Body-Size and Trophic Structure Dynamics

PLOS ONE, 2015

As the intensity and speed of environmental change increase at both local and global scales it is... more As the intensity and speed of environmental change increase at both local and global scales it is imperative that we gain a better understanding of the ecological implications of community shifts. While there has been substantial progress toward understanding the drivers and subsequent responses of community change (e.g. lake trophic state), the ecological impacts of food web changes are far less understood. We analyzed Wabash River fish assemblage data collected from 1974-2008, to evaluate temporal variation in body-size structure and functional group composition. Two parameters derived from annual community sizespectra were our major response variables: (1) the regression slope is an index of ecological efficiency and predator-prey biomass ratios, and (2) spectral elevation (regression midpoint height) is a proxy for food web capacity. We detected a large assemblage shift, over at least a seven year period, defined by dramatic changes in abundance (measured as catchper-unit-effort) of the dominant functional feeding groups among two time periods; from an assemblage dominated by planktivore-omnivores to benthic invertivores. There was a concurrent increase in ecological efficiency (slopes increased over time) following the shift associated with an increase in large-bodied low trophic level fish. Food web capacity remained relatively stable with no clear temporal trends. Thus, increased ecological efficiency occurred simultaneous to a compensatory response that shifted biomass among functional feeding groups.

Research paper thumbnail of Application and transferability of Great Lakes coastal wetland indices of biotic integrity to high quality inland lakes of Beaver Island in northern Lake Michigan

and regulatory agencies to categorize the condition of a given ecosystem. IBIs are more widely us... more and regulatory agencies to categorize the condition of a given ecosystem. IBIs are more widely used in lotic systems and those that can be used over wide geographic regions or multiple systems are deemed most valuable. Lacustrine wetlands have intrinsic complexity and multidimensionality making them very difficult to classify. This, in turn, greatly affects the transferability of indices created for explicit regions and wetland types. Similarly, due to scarcity, relatively pristine reference conditions are seldom included in IBI calibration and represent a critical end of the disturbance continuum.

Research paper thumbnail of Impacts of Agricultural Drainage Outlets on Great Lakes Coastal Wetlands

Research paper thumbnail of Lakewide Estimates of Alewife Biomass and Chinook Salmon Abundance and Consumption in Lake Ontario, 1989–2005: Implications for Prey Fish Sustainability

Transactions of the American Fisheries Society, 2010

Stocking levels of Chinook salmon Oncorhynchus tshawytscha for Lake Ontario have been highly cont... more Stocking levels of Chinook salmon Oncorhynchus tshawytscha for Lake Ontario have been highly controversial since the early 1990s, largely because of uncertainties about lakewide abundance and rates of prey consumption. Previous estimates have focused on years before 1995; since then, however, the Lake Ontario ecosystem has undergone substantial changes, and there is new evidence of extensive natural recruitment. Presented here are new abundance estimates of Chinook salmon and alewives Alosa pseudoharengus in Lake Ontario and a reevaluation of the potential risk of alewife population collapse. We found that Lake Ontario has been supporting, on average (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), 1.83 3 10 6 (range, 1.08 3 10 6 to 3.24 3 10 6 ) Chinook salmon of ages 1-4, amounting to a mean annual biomass of 11.33 3 10 3 metric tons (range, 5.83 3 10 3 to 23.04 3 10 3 metric tons). During the same period (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), the lake supported an alewife biomass of 173.66 3 10 3 metric tons (range, 62.37 3 10 3 to 345.49 3 10 3 metric tons); Chinook salmon of ages 1-4 consumed, on average, 22% (range, 11-44%) of the alewife biomass annually. Because our estimates probably underestimate total consumption and because Chinook salmon are only one of several salmonine species that depend on alewives, predation pressure on the Lake Ontario alewife population may be high enough to raise concerns about long-term stability of this predator-prey system.

Research paper thumbnail of Feeding Strategies and Diets of Young-of-the-Year Muskellunge from Two Large River Ecosystems

North American Journal of Fisheries Management, 2012

We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy samp... more We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy sampled in New York waters of the St. Lawrence and upper Niagara rivers to (1) describe diets and document use of nonnative prey, (2) examine the feeding strategy (generalized versus specialized) and the importance of different prey types, (3) evaluate temporal patterns in feeding strategy and prey importance, and

Research paper thumbnail of Assessment of remnant unionid assemblages in a selection of Great Lakes coastal wetlands

Journal of Great Lakes Research, 2013

Research paper thumbnail of Use of wetland versus open habitats by round gobies in lakes Michigan and Huron: Patterns of CPUE, length, and maturity

Journal of Great Lakes Research, 2012

ABSTRACT It has been suggested that some Great Lakes coastal wetlands may be resistant to invasio... more ABSTRACT It has been suggested that some Great Lakes coastal wetlands may be resistant to invasion by several non-indigenous species including round goby, Neogobius melanostomus. However, there is inconclusive evidence regarding how susceptible exposed fringing coastal wetlands, in particular, are to round goby invasion. Therefore, we quantified round goby catch per unit effort (CPUE) using fyke nets in the Beaver Archipelago of Lake Michigan, and the Les Cheneaux islands and Saginaw Bay regions of Lake Huron. In addition, we examined the influence of body size and maturity on round goby habitat use. Catch per unit effort from fyke nets was highest in the Beaver Archipelago, where wetlands were dominated by small, immature round gobies and open water habitats were dominated by large adults. Fyke net catches within Les Cheneaux sites were similar between habitats and differences in size and maturity were not observed. Conversely, very few round goby were captured in wetlands of Saginaw Bay where CPUE was moderate in open water. This indicates that some exposed fringing wetlands in the Great Lakes, specifically those with high productivity, could have a higher degree of resistance to round goby invasion.

Research paper thumbnail of Majority of age-3 Chinook salmon (Oncorhynchus tshawytscha) in Lake Ontario were wild from 1992 to 2005, based on scale pattern analysis

Journal of Great Lakes Research, 2009

Stocking of hatchery-raised Chinook salmon has been the principal tool utilized by fishery manage... more Stocking of hatchery-raised Chinook salmon has been the principal tool utilized by fishery managers for controlling alewives in Lake Ontario and elsewhere in the Great Lakes. Stocked Chinook salmon are also often viewed by anglers as the principal source of maintaining catch rates. Stocking levels are often controversial and set with limited information about the relative contribution of wild fish to lake-wide populations. Recent research documenting large numbers of age-0 fish in tributaries suggested that wild reproduction was increasing and greater than previously thought. Estimating the contribution of wild Chinook salmon is imperative for successful management of this economically important recreational fishery. To differentiate wild from hatchery-derived Chinook salmon, we developed and validated a classification rule from scale pattern analysis of known-origin fish that was based on the area of the scale focus and the distance between the scale focus and the first circulus. We used this technique to determine the annual proportion of anglercaught, age-3 wild Chinook salmon in Lake Ontario from 1992 to 2005. On average over 14 years, the annual proportion of wild age-3 Chinook salmon was 62% (± 13.6%, 95% CI), but has varied between 24% (± 9.4%) and 82% (± 11.2%). Wild fish have been a high proportion of the Chinook salmon population in Lake Ontario since the late 1980s throughout a period when the lake underwent considerable changes, suggesting that wild and hatchery-origin Chinook salmon are both important components for managing the predator-prey dynamics in Lake Ontario and maintaining angler catch rates.