Fish Biologist Part-Time

Company Overview

Environmental Science Associates (ESA) is a 100% employee‑owned environmental consulting firm. We plan, design, permit, mitigate, and restore projects across communities, infrastructure systems, open spaces, and wildlands. With 21 offices across California, the Pacific Northwest, and the Southeast, we have 50 years of experience in environmental consulting.

ESA is looking for a part‑time fisheries biologist to join the Fish and Aquatic Sciences team in Northern California. This variable part‑time professional will conduct specialized fisheries and aquatic field investigations, including fish population monitoring, water quality and hydrologic monitoring, and compliance monitoring for terrestrial and aquatic species. A minimum of five years of professional experience is required, along with experience operating and trailering boats, using a wide range of fish and water quality sampling gear, and performing light maintenance on equipment.

• Conduct fisheries and water quality investigations using various sampling gear across California.
• Provide excellent time/budget management, organizational capability, attention to detail, and strong problem‑solving skills.
• Collaborate with interdisciplinary teams to deliver projects on time and within budget.
• Apply standard techniques, methods, and procedures for a range of moderate‑complexity tasks.
• Use fish collection gear (electrofishing units, nets, traps, water quality sampling gear) to collect data on fish populations.
• Use water quality and hydrologic sampling gear (sondes, data loggers, ADCP units).
• Operate and trailer a variety of boats.
• Maintain vessels, including service records, routine oil changes, repair support, and comprehensive scheduling of services.
• Perform compliance monitoring for terrestrial and aquatic species, including hydroacoustic surveys, fish rescues, and compliance‑related water quality monitoring.

• Field‑focused fisheries technician/biologist with passion for monitoring fisheries populations and collecting high‑quality environmental data.
• Minimum of 5 years of experience in fisheries or aquatic biology.
• Extensive experience operating and trailering boats, using fish and water quality sampling gear, and maintaining sampling equipment.
• Ability to manage multiple responsibilities and deadlines in fast‑paced, challenging environments.
• Physical stamina to walk long distances carrying a backpack and lift at least 50 pounds.
• Comfortable working outdoors in remote, rural, urban, and variable weather conditions, with occasional night or weekend work.

$35 – $50 USD per hour, depending on experience, education, and location.

Eligibility for ESA’s sick leave program, employee stock ownership plan, and tax‑deferred 401(k) plan if applicable.

ESA is an Equal Opportunity Employer, committed to a diverse and inclusive work environment. (EOEM/V/F/D)