Effective. Professional. Experienced.

Zentner Planning and Ecology is a professional consulting firm specializing in wetlands, endangered species and other biological resources headquartered in Oakland, California. We are a certified Small Business Enterprise (SBE) with the State of California, the Port of Oakland, and the Valley Transportation Authority (VTA). We are:

  • Effective: We have successfully completed projects throughout the western United States, ranging from large residential subdivisions and new towns to infrastructure projects combining flood control and habitat restoration.
  • Professional: We pride ourselves on accurate work, the development of practical plans that meet or exceed our client’s goals, and the successful conclusion of our permit and habitat mitigation efforts.
  • Experienced: Zentner Planning and Ecology was founded in 1986—we have more than 30 years of professional experience in our field. Our clients like what we do for them – over 70% of our work comes from repeat clients


Please click on this link to view staff resumes.

John Zentner, Senior Manager - Founder
John Zentner is a plant ecologist by training with an avid interest in habitat restoration. John has over 30 years of experience in wetland science, stormwater treatment, permit processing and restoration. He specializes in federal and state policies and regulations, wetland boundary determinations, and mitigation programs. John has been a principal project manager for numerous environmental assessments, C3 stormwater plans, habitat boundary and mitigation plans, Section 404 (Clean Water Act) permit approvals and has worked as an expert witness. In addition to his role at Zentner Planning and Ecology, Mr. Zentner is a founding Board member for the Restoration Trust.

Brian Davis, Managing Partner
Brian Davis has a long background in small business management, entrepreneurship and environmental studies, including over 20 years of experience as the controller of Zentner Planning and Ecology. He has also consulted with numerous environmental and engineering firms on emerging markets, small business and minority business enterprises. With his expertise in both business and the environment, he specializes in marketing and other business requirements for small firms in the environmental consulting field.

Sean Micallef, Partner-Chief Ecologist
Sean Micallef has more than 20 years of experience in all aspects of environmental consulting. He specializes in project management for complex projects involving multiple permits, federal and state wetland and species permitting, and ecological fieldwork residential, industrial, energy and coastal actions. Sean specializes in ecological monitoring, managing special status plant and wildlife surveys and assessments, and preparing wetland determinations and mitigation plans.

Christopher Long, Ecological Designer - Assistant Project Manager
Christopher Long has a background in both visual design and Water Resources Management. He specializes in environmental planning and wetland restoration with over 5 years of experience and several fields of graduate coursework relating to natural resources. For Zentner Planning and Ecology, he conducts wetland delineations, pre-construction surveys, and prepares permit applications. He also conducts drone operations for aerial observation and analysis.

Emily Mathews, Project Manager - Biologist
Emily Mathews has a background in Marine Biology and her focus has been on habitat restoration, endangered species, biological monitoring, and project management. She has over 5 years of experience in community engagement and working in a variety of wetland and plant communities. She works on permit processing, vegetation and wildlife surveys, wetland delineation processing, and project implementation and management.

Consulting Staff

Dr. Glen Holstein
Dr. Glen Holstein consults as a Senior Ecologist with Zentner Planning and Ecology. He has more than 20 years of experience assessing biological resources and is one of the leading ecologists in the Western United States.

David Self
David Self consults as a Senior Ecologist with Zentner Planning and Ecology. He has more than 25 years of experience in plant and wildlife ecology and habitat restoration and is one of four individuals in the State of California certified by the U.S. Army Corps of Engineers as a Wetland Delineation Trainer.

Jeff Glaspy
Jeff Glaspy is a Restoration and Revegetation Specialist who consults for Zentner Planning and Ecology. A Certified Nurseryman, Mr. Glaspy has more than 30 years of experience in working with plants. Mr. Glaspy has his general contractors license and manages the grading, irrigation, and planting of restoration sites throughout California.