Our interdisciplinary team of environmental science, landscape architecture, and ecological design experts examine problems from multiple perspectives. We create individualized solutions tailored to each of our clients’ specific needs. Great Ecology’s staff members are trained in ecology, environmental sciences, landscape architecture, ecological design, hydrology, and planning. Our field staff are OSHA-certified to conduct work on hazardous sites.
Mark S. Laska, Ph.D. – President & Founder
Dr. Mark Laska is the Founder and President of Great Ecology. He has over 25 years of experience as an ecologist, focusing on wetland and habitat restoration, habitat and species assessments, ecological planning and design, and Natural Resource Damage (NRD) Assessments and Planning. His work in ecological restoration involves the planning, design, evaluation, permitting, and management of restoration projects. The author of more than a dozen scientific papers, Dr. Laska has developed a niche practice at the intersection of business and science with significant focus on environmental credit trading of habitat restoration projects. Dr. Laska holds a Doctorate in Ecology and Evolution from Rutgers University.
Jessa Spainhower – Vice President, Operations
Jessa Spainhower is the Vice President of Operations at Great Ecology. Jessa applies her expertise in data analytics, and exceptional organizational skills, to inform short- and long-term strategic planning within the Operations department and across the company. As part of this strategic planning, Jessa participates on the Executive Committee. She acts as Great Ecology’s human resources manager, and oversees the company’s project, business, and IT administration. She creates and rolls out protocol and policies to support the firm’s continued growth; and manages overall business administration, including analyzing and reporting on key business metrics. She has more than a decade of experience as a research analyst and operations manager. Jessa has a double major in Business Management and Marketing from Northwest Missouri State University.
Damian Holynskyj, M.C.P. – Regional Director, Eastern
Damian has over thirteen years of experience as an ecologist and environmental land planner. Working in both the public and private sector, his professional focus has been on land planning issues related to habitat restoration, regenerative land development, and green building design and construction. He has dedicated much of his career to developing practical and feasible cost-effective solutions that at a minimum reduce the detrimental effects of the built environment on local ecology, but ideally create healthier and more resilient landscapes. Damian has extensive experience in procuring funding for and managing the design and approvals of large-scale ecological restoration projects throughout the mid-Atlantic, as well as managing the design, approvals, and marketing for numerous mitigation banks. Mitigation credits sold from these mitigation banks can be used to offset impacts to regulated resources, such as wetlands, streams, and land within the riparian zone. Damian is a member of the American Institute of Certified Planners (AICP) and is also a certified Passive House Consultant. He holds a BS in Environmental Science from Rutgers University and a Masters of City and Regional Planning from the University of Pennsylvania.
Joshua Eldridge, M.S. – Regional Director, Mountain
Joshua Eldridge is an ecologist with over twelve years of experience, including nine years as an ecological consultant. He directs the Great Ecology Intermountain West Ecology Team and specializes in the planning, design, management, and monitoring of habitat restoration and ecological research projects. His diverse and extensive portfolio includes mine land reclamation, brownfield, and urban restoration projects across the United States and Australia, including Denver, Colorado, Great Falls, Montana, Louisville, Kentucky, and Kalgoorlie, Western Australia. In addition, he has experience collecting vegetation, soil, and water samples from hazardous waste sites in Colorado, Montana, and Nevada. His experience includes project management on complex, multi-year permitting and redevelopment projects, rare or endangered species surveys, assessments of disturbed riparian and upland systems, surface and ground water sampling, park redesign, stream and wetland mitigation design, and wetland delineations. Joshua is skilled in the principles of restoration ecology, ecosystem evaluations, sampling design, and technical writing. He attended Colorado State University where he received his Bachelor’s degree in Natural Resource Management with a minor in Watershed Science and Master’s degree in Restoration Ecology.
Laurel Glass Lees – Regional Director, Western
Laurel Glass Lees has over 10 years of experience as a land use and environmental planner, focusing on the triple bottom line approach to developing and managing the built and natural environment in line with local, state, and federal regulations. Laurel is well versed in the California Environmental Quality Act and her knowledge has been applied to projects requiring long-range sustainability planning and land use policy. With a strong background in environmental science, economics and policy, Laurel works with teams to develop strategic solutions to complex problems that impact stakeholders from business, community and environmental groups. Her experience as a planner and project manager in both the public and private sectors provides a holistic understanding of the various nuances that may affect a project’s scope, schedule and budget. As the team leader of various sustainability-related projects and programs, Laurel provides technical expertise in water, energy and climate planning and implementation. She holds a Bachelors in Environmental Studies and Economics from the University of San Diego, and Professional Certificates in Urban Planning & Development and Grant Writing from University of California San Diego and San Diego State University, respectively.
Nick Buhbe, M.S. – Senior Managing Ecologist
Nick Buhbe has 18 years of experience, specializing in sediment testing, ecological health assessments of various biological communities, water quality studies, preparation of environmental planning compliance documents, and freshwater wetland-related project work. His portfolio includes physical, chemical, and biological evaluations of sediments in three major southern California harbors, as well as ports across the Pacific. He is well-versed in the Clean Water Act and the Marine Protection, Research, and Sanctuaries Act. His extensive knowledge of the marine environment has been instrumental in informing environmental planning, National Environmental Policy Act compliance, and California Environmental Policy Act documents. He holds a Master’s degree in Biology and a Bachelor’s degree in Marine Biology.
David J. Yozzo, Ph.D. – Senior Managing Ecologist
Dr. David Yozzo is a nationally recognized estuarine scientist with 19 years of experience. His portfolio includes navigation improvement projects throughout the Hudson-Raritan Estuary, New England, Chesapeake Bay and the Gulf of Mexico. Dr. Yozzo has conducted research on tidal wetland fish/invertebrate communities in the New York-New Jersey Harbor and has conducted baseline and post-construction environmental surveys for habitat restoration projects conducted by USACE, NYSDEC, NYCDEP, NYCEDC, NOAA, and the Port Authority of NY-NJ. In addition, Dr. Yozzo co-authored the USACE National Guidebook to Hydrogeomorphic Assessments in Tidal Fringe Wetlands and has participated in several regional applications of the HGM methodology in the New Jersey Meadowlands and in the north-central Gulf of Mexico. Recent projects include the planning, design and implementation of several ecosystem restoration pilot projects for the NYCDEP CSO-PlaNYC project; a programmatic review of habitat restoration within NOAA’s National Estuarine Research Reserve System, developing an Ecological Site Profile for the Hudson River Reserve, and remedial dredging/habitat restoration at Springfield Gardens Lake, Queens, NY, for NYCEDC and NYCDEP. Dr. Yozzo is Past-President of the Atlantic Estuarine Research Society, and has served on the Governing Board of the Coastal and Estuarine Research Federation. He also serves as an Adjunct Associate Professor of Environmental Studies at Purchase College, SUNY. Dr. Yozzo holds a Master’s degree and a Doctorate in Environmental Science from the University of Virginia.
Jill McGrady, Ph.D. – Senior Ecologist
Dr. Jill McGrady has over 10 years of experience in the fields of ecology and ecosystem studies. Her work focuses on restoration evaluation, planning, and development of Natural Resource Damage (NRD) strategy following environmental impacts from mining, refinery, oil spill, and other contamination events. Dr. McGrady currently manages a large-scale, comprehensive restoration planning project spanning several coastal states. She has multiple publications in leading academic journals and holds a Bachelor’s degree in Biology from Allegheny College, a Master’s degree in Ecology and Evolutionary Biology from Purdue University, and a Doctorate in Ecology and Evolution from Rutgers University.
Mitchell J. Hart – Professional Engineer
Mitchell J. Hart is a Professional Engineer (P.E.) with 35 years of experience in mined land reclamation and remediation. Most recently, Mitch managed a large portfolio of historic/legacy mine sites totaling more than 4,000 acres, with annual budgets of more than $20 million, implementing remedial/removal actions to reduce environmental impacts. Mitch builds effective relationships with regulatory agencies at the local, state, and federal levels and served for eight years as a member of the (Idaho and Utah) Bear River Basin Advisory Group, authorizing a multitude of projects related to improvements in water quality, grazing practices, fish passage, and land/water conservation. He has provided expert testimony in “Mining and Reclamation – Customs, Standards and Practices” and is a published author and presenter of topics related to: Selenium Attenuation; Industrial Site Closures; By-Product Re-use; and Carbon Calcining. Mitch is a Past President of the Association of Idaho Cities (AIC), consisting of 200 member cities, and continues to serve as a member of the Executive Committee of AIC. He holds a Bachelor of Science (B.S.) degree in Mining Engineering from the University of Utah.
Chris Loftus, PLA – Senior Landscape Architect
Chris is a Professional Landscape Architect with over thirteen years of experience working in the western United States. Chris has worked on projects throughout Colorado and the West, including several award-winning designs. His project experience includes planning and design of parks, trails, and open space; neighborhood and community master planning; innovative stormwater design solutions; urban streetscape design; visual resource assessments and simulations; and ecological restoration design and planning. In close collaboration with Great Ecology’s ecologists and designers, Chris develops strategic design solutions that increase ecological functionality and, where appropriate, incorporate public access components. He is registered in the states of Colorado and California. He serves as Vice President of Programs for the American Society of Landscape Architects (ASLA) Colorado Chapter and on the Ecology + Restoration Professional Practice Network (ASLA) leadership team. He is a Council of Landscape Architectural Registration Boards (CLARB) Certified Landscape Architect and holds a Bachelor of Science in Environmental Studies from University or Oregon and a Bachelor of Science in Landscape Architecture from Colorado State University.
Ashley Tuggle, M.E.M. – Associate Ecologist
Ashley Tuggle is an environmental scientist specializing in freshwater ecology and stormwater management. She has significant experience in water quality modeling, wetland field surveys, and land use planning in North Carolina and the Appalachian region. Ashley also has a strong technical background in geospatial analysis, GIS, and statistical analysis. She holds a Bachelor’s degree in Environmental Studies from Franklin College Switzerland and a Master’s degree in Environmental Management and Certificate of Geospatial Analysis from the Nicholas School of the Environment at Duke University.
Esa Crumb, M.S. – Associate Ecologist
Esa Crumb is an ecologist with over ten years of experience in the fields of wetland and plant ecology, restoration planning, and environmental permitting. Esa is well-versed in the intricacies of Clean Water Act Section 404 permitting, Endangered Species Act consultation, and natural resource assessments. She has worked on wetland restoration and mitigation planning projects in coastal regions of California and in the Rocky Mountains of Colorado, with multidisciplinary roles that include technical surveys, feasibility studies, functional assessments, and regulatory compliance. Esa has significant experience conducting natural resource surveys in the Colorado high country, including specialized training in identification and mapping of sensitive aquatic resources such as fens. She holds a Bachelor of Science degree in Molecular, Cellular, and Developmental Biology and minor in Biochemistry from the University of Colorado at Boulder, and a Master of Science degree in Ecology and Systematics from San Francisco State University.
Ellie Garza, PLA – Associate Landscape Architect
Ellie is a professional landscape architect with over four years of experience as a designer and a project manager. Her professional background includes working for public and private sector clients, providing comprehensive, ecologically-sound design solutions that augment the surrounding community. Her project experience includes analysis and planning; design development and construction documentation of parks, trails, greenway, open space, and river corridors; public-led planning, including presentations and communication; municipal development plan review; and visualization communications. She has collaborated with ecologists, trail builders, environmental planners, and engineers to provide holistic design solutions from the planning level to site-specific design. She is a Council of Landscape Architectural Registration Boards (CLARB) Certified Landscape Architect and holds a Bachelor of Landscape Architecture from Texas A&M University with a minor in Urban and Regional Planning. She is a certified small unmanned aircraft systems commercial remote pilot.
Justin Apfel – Ecologist
Justin Apfel is an ecologist, with experience in wetland permitting, tidal and non-tidal stream assessments, Geographic Information System (GIS), subsurface contamination investigations, and stormwater management. His expertise is in wetland delineations and assessments with a heavy focus on the development of large scale solar energy projects. He holds a Bachelor of Science degree in Environmental Biology with a minor in Chemistry from Christopher Newport University and is a Wetland Professional In Training (WPIT) through the Society of Wetland Scientists (SWS).
Justin Heyerdahl, MESM – Ecologist
Justin Heyerdahl is an environmental scientist with a hybrid skillset in geographic information systems (GIS), data science, and storytelling. Justin uses spatial and non-spatial analytics to help leverage ecological processes for building resilience through design and planning projects, while also crafting compelling, data-driven narratives for stakeholder communication. With a background in landscape and quantitative ecology, Justin specializes in modeling species distribution, landscape connectivity, and climate change adaptation. Past work includes modeling forest and fire resilience in the Sierra Nevada under various vegetation management and climate scenarios. He holds a Master of Environmental Science and Management (MESM) from the Bren School at the University of California Santa Barbara, a Bachelor of Arts in Communication from Northwestern University, and a Certificate in Global Sustainability from the University of California Los Angeles.
Emily Hazelwood, M.A.S. – Ecologist
Emily Hazelwood is an ecologist, with experience in conducting both international and domestic environmental impact assessments, her key area of expertise is in offshore oil and gas development and decommissioning- with a focus on the economic and environmental impacts of developing and implementing international Rigs-to-Reefs programs. She specializes in ecological evaluations of offshore resources, kelp forests and wetland restoration projects, and biodiversity baseline management studies. Ms. Callahan has had diverse experience in marine and terrestrial field sampling as well as a strong background in biological monitoring programs. She holds a Bachelor’s degree in Environmental Studies from Connecticut College and a Master’s degree in Marine Biodiversity and Conservation. She is a PADI certified dive master and an AAUS Scientific Diver with over 800 hours of logged dives.
Amber Sparks, M.A.S. – Ecologist
Amber Sparks is an oceanographer, marine conservation biologist and oil and gas consultant. Her expertise is unique, specializing in ecological impact assessments, marine biological monitoring, and habitat restoration through the Rigs to Reefs program. She has both international and domestic experience working in the field of offshore oil and gas decommissioning, and uses her background in science communication and technology to distill and relate complex concepts in ocean science for a variety of audiences. Her previous work centered around the ecological, socioeconomic, regulatory, and policy issues surrounding the active implementation of a Rigs to Reefs program in California and internationally.
Alejandro Baladrón Julian, M.S. – Environmental Consultant / Hydrologist
Alejandro Baladrón Julian is an environmental scientist specializing in hydrology with 9 years of experience in public and private sector projects. Before receiving his Certificate in Conservation Biology from Fordham University, he worked as an environmental consultant in Spain for five years. His portfolio includes Environmental Impact Assessments, biological investigations, ecological restoration of urban streams and wetlands, environmental monitoring on construction sites, water quality assessments, and hydrology modeling, including the design of drainage networks for highway and railway lines, the analysis of evacuation capacity in wastewater drainage systems, and flood risk studies. Alejandro has ample experience performing advanced mathmatical modeling and stats analysis to support decision-making in civil engineering, landscape architecture and environmental projects. He also assisted the Spanish Government for four years in the preparation of technical reports and cost-benefit analyses to request funds for the construction of water supply projects in the Mediterranean Coast under the European Regional Development Funds (ERDF) Program. Alejandro holds a Bachelor’s degree in Environmental Sciences, a Master’s degree in Applied Hydrology, and a Master’s of Advanced Studies in Environmental Sciences.
Carlos Rivero Moro, M.S. – Environmental Consultant / Sustainability Expert
Carlos Rivero Moro is an environmental scientist specializing in sustainability and climate change adaptation. He worked for 7 years as a consultant and participated in multiple public and private sector projects providing assistance in a broad range of subjects, including environmental permitting, the design of Environmental Management Systems, and the design and surveillance of energy efficiency programs and energy efficiency scorecards. He also has worked for 3 years as the Environmental Business Development Manager in a multinational certification company. In addition, he has wide experience performing international projects related to Carbon and Water Footprint, Environmental Product Declarations and GHG emissions management. Carlos holds a Bachelor’s degree in Environmental Sciences, and a Master’s in Environmental Pollution.
Liz Clift, MFA – Copy Editor
Liz Clift is responsible for marketing and quality assurance of client deliverables. She has worked as a technical writer, editor, and grant writer for more than 10 years, and has taught college composition and experiential education courses. She is also a creative writer, and has published a variety of short stories, poems, and essays, including a regular column for Denver Metro Media. She holds a Bachelor’s degree in Environmental Studies from Elon University and a Master of Fine Arts in Creative Writing & Environment from Iowa State University.
Lilia Gavrilenko, M.S. – Controller
Lilia Gavrilenko handles the daily accounting activities for Great Ecology. She has over seven years of experience in accounting and budgeting. Lilia holds Master’s degree in Mathematics and Bachelor’s in Accounting.
Alexa Rosenstein – Office Manager
Alexa Rosenstein is the office manager for Great Ecology’s Denver location. She previously worked for a technology startup in the areas of business development and process engineering, and later moved into a management role. In addition to handling the day-to-day office needs in Denver, she supports the operational and administrative side of the business. She attended the University of Virginia and graduated with a Bachelor’s degree in Leadership and Public Policy from the Frank Batten School.
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Daniel R. Brumbaugh, Ph.D.
Dr. Daniel R. Brumbaugh, a marine ecologist with over 20 years of experience, specializing in coral reef ecology, focusing on reef monitoring techniques, studies of coral recruitment, and the science and management of marine protected areas. For 12 years, Dan studied coral reef and other marine ecosystems in The Bahamas and applied this knowledge to Bahamian marine conservation and education. During this time, he led a number of interdisciplinary investigations, including the Bahamas Biocomplexity Project, to study how an expanding system of marine protected areas in the country could function. He also participates on the governing Council and Scientific Advisory Committee of the Bahamas National Trust, and has advised the Bahamas Department of Marine Resources (then Fisheries) on applications of marine science to reserve planning. In the U.S., Dan has served on the stakeholder Advisory Council of the Channel Islands National Marine Sanctuary and as a Visiting Scientist with the U.S. National Marine Protected Areas Center. He also is also an individual member of the World Commission on Protected Areas (WCPA, part of the World Conservation Union, or IUCN) and is on the Advisory Board of the non-profit OneReef, which facilitates reef conservation agreements between funders and reef-owning communities in Micronesia.
Dennis Corelli, PWS
Dennis Corelli has over 27 years of experience with environmental projects including: site quality assurance, biological and media sampling, wetland delineations, natural resource inventories, and subsequent preparation of environmental documents and permits. He has worked on projects in New York, New Jersey, Connecticut, Pennsylvania, Massachusetts, Wisconsin, Florida, Delaware, and Puerto Rico. Through the U.S. Environmental Protection Agency (USEPA), Region 2 Superfund Alternative Remedial Contracting Strategy (ARCS) program, and the U.S. Army Corps of Engineers (USACE), he has gained extensive field experience, completed many permit applications, and developed remedial investigation reports. He graduated from Marist College with a Bachelor’s of Science degree in Environmental Science.
Joseph Ehrenberger, M.S.
Joseph Ehrenberger’s career of 11 years as an ecologist includes a broad diversity of skills and experiences, with an emphasis on wildlife and habitat assessments. His portfolio includes assisting with husbandry and breeding of rare species in the U.S., Dominican Republic, and Grand Cayman. His field experiences concentrated on general wildlife and habitat assessments, as well as special-status species surveys (e.g. Greater sage grouse, Lesser prairie chicken, Mexican spotted owl, Indiana bat, Swift fox, raptor nest monitoring, Ricord’s iguana, and plants such as the Ute’s ladies tresses and Colorado butterfly plant). His habitat work includes restoration for Preble’s meadow jumping mouse and Kremmling milkvetch, as well as rangeland noxious weed management, mountain pine beetle control, and energy development mitigation. Most recently, he conducted focused surveys throughout Colorado for amphibians and reptiles, including rattlesnake management projects and safety training for governments and the private sector. He has authored numerous technical publications and agency documents. Furthermore, his coordination of volunteers has proven essential to non-profit and federal species and habitat monitoring programs. Joseph received his Bachelor’s degree in Teaching from Virginia Tech and his Master’s degree in Ecology from Indiana State University.
Linda B. Gumeny, RLA, LEED AP-ND
Throughout Linda Gumeny’s 30-year career she has worked on a wide variety of public and private sector projects ranging from large-scale master planning to small-scale site design. She has served as both project director in the prime consultant role, and project landscape architect in a sub-consultant role for complex, multi-disciplined projects. Her work is focused on developing sustainable design solutions for parks, open space, residential, commercial, and institutional developments. Linda holds a Bachelor of Science degree in Landscape Architecture from Cornell University, and is a licensed landscape architect in NY, NJ, & CT. She is also a LEED AP-ND, accredited professional in neighborhood development.
Kim Raby Lennberg, M.S.
Kim Raby Lennberg is a watershed scientist with 14 years of experience investigating the scientific, technical, and policy aspects of a broad range of environmental subjects, specializing in using an interdisciplinary approach to watershed science and characterization. Kim’s professional expertise includes monitoring and assessing watershed health by examining the chemical, physical, biological, and hydrological characteristics of aquatic ecosystems; designing, coordinating, managing, and conducting extensive ecological and aquatic field investigations; and authoring technical reports communicating the results of short- and long-term studies, as well as substantial portions of NEPA- and CERCLA-related documents. Her current areas of study and interest focus are on stream restoration and aquatic habitat evaluation and improvement. Kim’s most recent project work includes evaluation of river restoration projects through aquatic and riparian habitat quality assessment, monitoring and reporting assistance related to flood recovery, and management of fishery and aquatic resource monitoring and reporting projects in areas impacted by phosphate mining. Kim holds a Bachelor’s degree in Environmental Systems Technology from Cornell University, a Master’s degree in Environmental Studies (with a focus on alpine hydrology) from the University of Colorado at Boulder, and a Professional Certificate in River Restoration from Portland State University.
John C. Lovio, M.S.
John Lovio is a field and conservation planning ecologist with over 30 years of professional experience in biological assessments, species surveys, environmental regulatory compliance, and ecological research in the western states, particularly California. He specializes in the habitat relations, biogeographies, and landscape ecologies of wildlife, particularly birds, with special interest in establishing ecological baselines and perpetuating long-term ecological studies to measure effects of land use changes and climate change. He is experienced in assessing land condition and conservation value, as well as anticipating and evaluating habitat disturbance (including wildfire) effects and restoration efforts in a wide range of aquatic, estuarine, and terrestrial natural environments. John Lovio holds a Master’s degree in Biology-Ecology from San Diego State University and a Bachelor’s degree in Wildlife Biology from the University of California at Davis.
Phillip S. Rosenberg, P.G., C.E.G., C.Hg.
Mr. Rosenberg is a licensed Professional Geologist, Certified Engineering Geologist , and Certified Hydrogeologist with over 35 years of consulting experience, providing environmental and engineering consulting services to clients in both the public and private sectors. He has significant experience with complex sites with emerging or multiple contaminants, and provides expert witness testimony related to soil and groundwater contamination issues. He has interacted closely with local, state, and federal regulatory agencies. Mr. Rosenberg has significant experience in water quality, having worked on sites with both ground and surface water issues, including contaminants in surface water bodies. Mr. Rosenberg maintains professional licenses in Arizona, California, Missouri, Oregon, and Wyoming, and has a Bachelor’s degree in Geological Sciences from Bradley University.