Sean Avent

Senior Biologist


Sean Avent is an accomplished biologist and environmental scientist proficient in freshwater, estuarine, and marine environments. He received his BS degree in Oceanography with an emphasis in Biological Oceanography from the University of Washington in Seattle, WA. Sean spent nine years as an academic researcher with San Francisco State University working on projects on both coasts of the US, but chiefly in the San Francisco Bay-Delta system and coastal California Pacific Ocean.

Through his career in environmental consulting, Sean has managed and performed work on projects requiring wetland delineation, restorations and research, rare and endangered species permitting, environmental impacts assessment, and CEQA and NEPA document preparation. He is experienced with the preparation of biological documentation for Section 7 of the Endangered Species Act, permit applications for Clean Water Act Section 404 and Section 401, and Section 1600 Streambed Alteration Agreements, as well as mitigation and monitoring plans required as part of these permits. Sean has extensive experience in locar regulatory compliance reports such as the Marin County Stream Conservation Ordinance related permitting requirements. He has worked in concert with various state and federal regulatory agencies.

Sean’s areas of expertise include ecology and biology of species in central and northern California including birds, amphibians, invertebrates and fishes, particularly special status fishes of the San Francisco Bay-Delta system such as delta smelt, longfin smelt, Chinook salmon, steelhead, and Sacramento splittail. Sean has experience in invasive aquatic species such as zebra and quagga mussels and invasive estuarine fish and invertebrate species; bird monitoring, surveys, and depredations; habitat mitigation planning; lake management plans, restoration design, implementation and monitoring; essential fish habitat evaluations, and SCUBA surveys.

Sean is experienced in wildlife habitat evaluations and assessments, special status species surveys including California red-legged frog, California tiger salamander, burrowing owl, nesting birds, Swainson’s hawk, western pond turtle, Mojave ground squirrel, Berkeley kangaroo rat, salt marsh harvest mouse, and San Joaquin kit fox. His technical experience includes water quality monitoring, hydrologic surveys and monitoring, interaction of physical processes with biology, and theoretical ecological modeling.

Sean is currently involved in a number of small and large projects involving biological permitting, wetland restorations, mitigation and conservation bank analyses and creation, biological resource impacts analysis, CEQA documentation, and mitigation planning covering a wide range of biological habitats and species.


Marin County Parks Paradise Beach Park Seawall Protection Biological Resources Assessment and Initial Study, Marin County, California

Oddstad Way Residential Development, Pacifica, California

Exploratorium Relocation Project Permitting, San Francisco, California

Eelgrass and Submerged Aquatic Vegetation Surveys, Essential Fish Habitat Evaluation, Permitting, and Mitigation, San Francisco Bay and Delta, California

GraniteRock Aromas Quarry Pajaro River Environmental Compliance Services, California

Pittsburg Marina, Post-Dredge Submerged Aquatic Vegetation Surveys, Pittsburg, California

Riverview Park, Non-Motorized Boat Launch Permitting and Biological Monitoring, Pittsburg, California


B.S. Biological Oceanography, University of Washington, 1996


California Red-Legged Frog Workshop, Elkhorn Slough Coastal Training Program, 2009

Rare Pond Species Survey Techniques Workshop, Laguna de Santa Rosa Foundation & The Wildlife Project, 2009

California Tiger Salamander Workshop, Elkhorn Slough Coastal Training Program, 2008

Pond Turtle Workshop, Elkhorn Slough Coastal Training Program, 2009