Data Types
Upstream passage
Adult Upstream
Objective: Estimate spring-run spawning
population
Type: VAKI Riverwatcher
Location: Daguerre Point Dam
Times of operation: Year-round
In the Yuba River, a VAKI Riverwatcher™ video monitoring system is
operated within the two fish ladders (North and South) at Daguerre
Point Dam. This dataset is considered to be a census for spring
run chinook because mostly all spawn upstream of Daguerre Point
Dam. Passage estimates using the adult upstream data have been
modeled for 2004 – 2023. The modeling approach involves
determining the run and interpolating for missing data.
Data is available in tables following sequential QA/QC processes
and modeling:
Instantaneous passage records: data in this file form the base
dataset for analyses and methodologies identified in Poxon and
Bratovich (2020). These data are provided for transparency and are
not intended to be used for modeling purposes.
Uncorrected daily passage: data in this file represent the
aggregation of the instantaneous records in instantaneous passage
records to net upstream daily passage counts. These data undergo
the count correction and run differentiation analyses presented in
Poxon & Bratovich (2020). These data are provided for
transparency and are not intended to be used for modeling
purposes.
Corrected and run-differentiated daily passage: data in this file
are corrected for VAKI operational outages and contain run
differentiated daily net Chinook salmon passage estimates. Data in
this file represent the output (results) from the count correction
and run differentiation analyses presented in Poxon and Bratovich
(2020). Please see below for important notes regarding biological
years 2016, 2017, and 2019.
Interpolation of missing data (i.e., when the video system was not
working) is performed by application of a Generalized Additive
Model (GAM). Run differentiation is performed by splitting the
dataset into three temporal components (an early component of
early migrating spring run, a middle component comprised of late
migrating spring run and fall run, and a late component of fall
run) and conducting an iterative analysis to find the
best-supported ratio of spring run to fall run in the middle
component, as outlined in Poxon and Bratovich (2020).
The 2016 and 2017 annual time series were deemed inappropriate for
count correction and run separation analyses due to long periods
of VAKI Riverwatcher™ system outages that resulted in incomplete
datasets for both years. No estimates (run-differentiated or
overall) are possible for these years. The total number of Chinook
salmon for these years represent raw counts as affected by VAKI
Riverwatcher™ system outages, and do not represent estimated
annual abundances.
Additionally, run-type differentiation was not possible for
biological year 2019 due to an extended closure (February 13, 2019
through September 10, 2019) of the DPD North Ladder, which
fundamentally altered the temporal patterns of passage at DPD on
which the run differentiation analysis is based. As a result, the
only possible annual abundance estimate for the 2019 annual time
series is Total Chinook Salmon. Table 1 in Poxon and Bratovich
(2020), which did not acknowledge the limitations of 2019 data
precluding run differentiation, has been superseded by Table 1 in
Poxon and Bratovich (2023). Table 1 in Poxon and Bratovich (2023)
is also expanded to include results of count correction and run
differentiation analyses for biological years 2020 through 2022.
Resources
Poxon, B. and Bratovich, P. 2020. Lower Yuba River VAKI
Riverwatcher™ Chinook Salmon Passage and Run Differentiation
Analyses – 2020 Update. Prepared by HDR for Yuba Water Agency.
Poxon, B. and Bratovich, P. 2023. Summary Table of Results for
Lower Yuba River VAKI Riverwatcher™ Chinook Salmon Passage and Run
Differentiation Analyses for Biological Years 2004-2022. Prepared
by HDR for Yuba Water Agency.