Using Benthic Macroinvertebrates to Assess Freshwater Aquatic Habitat in Copeland Creek, a Sonoma County Urban Waterway

Presenter: Hannah Aghajan

Co-Presenter(s):
Eva Brown

Presenter Status: Undergraduate student

Academic Year: 22-23

Semester: Spring

Faculty Mentor: Nick Geist

Department: Biology

Funding Source/Sponsor: Koret Scholars Program

Other Funding Source/Program: CEI

President's Strategic Plan Goal: Sustainability and Environmental Inquiry

Abstract:
Benthic Macroinvertebrates (BMI) serve vital roles in establishing aquatic ecosystem trophic structure and function. Understanding underlying biotic and abiotic factors that impact urban riverine BMI assemblages over time can reveal key information about ecosystem condition. Prioritization of creek drainage efficiency in urbanized areas over native ecosystem integrity often results in channelized waterways with artificially reinforced banks and flattened beds that result in degraded habitat quality. It has been demonstrated that the pools and riffles typical of more “natural” creek structures significantly influence biodiversity within these ecosystems. BMI were collected utilizing dip nets (D-nets) in measured sweeps; a standard method used in obtaining samples of aquatic invertebrate communities. In cases where water is too shallow for the use of D-nets (<1.5m), kick net sampling is employed. Both of these sampling methods have been utilized in tandem with standard BMI sampling protocols to apply in our assessment of water and habitat quality in Copeland Creek. Collected specimens were preserved in 70% ethanol before being identified taxonomically to at least family level utilizing aquatic invertebrate dichotomous keys and microscopy. Identified specimens were subsequently cataloged and analyzed for relative abundance and diversity for our evaluation of the effects of urbanization on water quality.