USFWS Delta Boat Electrofishing Survey for Fish Abundance Trends, 2018-2025

The United States Fish and Wildlife Service's Delta Boat Electrofishing Survey estimates spatial and temporal trends in fish abundance and occupancy within the Sacramento-San Joaquin River Delta. The survey, developed in 2018 by the USFWS Lodi Field Office and USGS, uses a stratified random sampling design and segmented transects for occupancy modeling in nearshore littoral habitats. Data is available via API and XML formats, with the last update recorded in April 2026.

Use Cases

• Modeling spatial and temporal trends in fish abundance based on the stratified random sampling design.
• Estimating species occupancy and capture probabilities using the segmented transect spatial replicates.
• Analyzing relationships between fish assemblages and environmental drivers mentioned in the survey objectives.
• Expanding fish monitoring inferences for nearshore habitats not covered by long-term beach seine surveys.

Strengths

• Survey employs a robust statistical framework including a stratified random sampling design.
• Designed to provide spatial and temporal trend data from 2018 to 2025.
• Developed in collaboration between USFWS and the United States Geological Survey.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and dataset size are unknown, which may limit suitability assessment.
• Data may reflect geographic bias inherent to the Sacramento-San Joaquin River Delta.

Provenance

Source

United States Fish and Wildlife Service, Lodi Field Office, in collaboration with the United States Geological Survey.

Collection Method

Boat electrofishing survey using a stratified random sampling design and segmented transects.

Time Range

2018-2025

Freshness

Last updated 2026-04-14 16:44:05.933340; freshness should be verified.

Geography

Nearshore littoral habitats within the Sacramento-San Joaquin River Delta, San Francisco Estuary.