Thomas Gast & Associates Environmental Consultants Services

Fisheries Consulting.

Instream Flow Studies

  • IFIM implementation
  • Hydraulic habitat modeling, 1D and 2D
  • Temperature modeling
  • Habitat time series analysis
  • Impact analysis

Fish Distribution and Abundance

  • Direct observation (snorkel surveys)
  • Active capture techniques (electrofishing, hook and line sampling)
  • Passive capture techniques (seine and gill nets, fyke net, rotary screw trap, minnow traps)
  • Quantitative population assessments (“Single Stream” and “Regional” estimates of fish abundance, Hankin and Reeves 1988; Dollof and Hankin 1993)
  • Mark-recapture studies
  • In-stream and riparian habitat assessments (habitat mapping, Large Woody Debris inventories)
  • Active telemetry, acoustic and radio tags, passive telemetry, PIT tags

Benthic Invertebrate and Periphyton Sampling

Watershed Restoration Planning/Implementation

Stream Flow Measurements

  • Acoustic Doppler Current Profiler (ADCP)
  • Wading with hand-held meters
  • Stream gauge installation

Water Quality Monitoring

  • Temperature
  • Dissolved Oxygen
  • pH
  • Conductivity, salinity, dissolved solids
  • Turbidity, suspended solids
  • Algae, phytoplankton, chlorophyll
  • Nutrients
  • Storm runoff/contaminant testing

Environmental Compliance Documentation

  • NEPA/CEQA reports
  • Environmental Assessments (EAs)
  • Regulatory permitting

Endangered Species Act (ESA) consultations

  • Federal (Sections 7 and 10)
  • California (Fish and Wildlife Code Sections 2080.1 and 2081)

ADCP Mapping

  • 3-diminsional Velocity mapping
  • Bathymetry mapping

Boat Support

Scientific Report Writing, Editing, and Review

Eelgrass Surveys

  • Sidescan sonar

Underwater Noise Monitoring

  • Pile driving