Description The purpose of this study is to expand IEP monitoring and inference to other dominant near-shore, littoral habitats not sampled by beach seines through the use of boat electrofishing. To accomplish this we will sample key littoral fish species across various near-shore habitats in order to determine how best to estimate abundance, occupancy, capture probabilities, and related environmental drivers. Need Expanding DJFMP sampling to other habitats throughout the Delta will allow our program to detect and monitor fishes and ecological trends through time, alleviating a recognized data gap. Current sampling relies on data collected through non-random fixed point sampling of unobstructed habitats, which limits the utility of our data to inform management decision. Objectives • Design boat electrofishing survey methods to expand DJFMP’s monitoring into habitats and locations not sampled by beach seining. • Design and develop field and data analysis methods for estimating capture probability and abundance using boat electrofishing techniques. • Predict spatio-temporal distribution of habitats occupied by key littoral species.
The Delta Juvenile Fish Monitoring Program was established in the 1970s to monitor juvenile salmon abundance in the San Francisco Bay-Delta using trawling and beach seine nets. Since then the DJFMP has expanded its objective and sampling efforts, most significantly in 2016, when the Enhanced Delta Smelt Monitoring Program was initiated as part of DJFMP. Today, the DJFMP continues to document the relative abundance, distribution and survival of juvenile salmonids and other fishes in the lower Sacramento and San Joaquin rivers, Delta and San Francisco Bay for the protection, recovery and management of naturally produced salmonids and other native species in the Central Valley of California. Monitoring Data All monitoring data are collected by the Lodi Fish and Wildlife Office. Daily and weekly summary reports are available in the Lodi FWO Monitoring Data collection. Raw preliminary data files are also available. Some of the more common data requests, such as Chinook salmon, steelhead and pelagic organism decline species (e.g., Delta smelt, longfin smelt, threadfin shad and striped bass) catch data — by survey as well as the Chipps Island survival calculations — have also been compiled. If you would like additional information or want to request specific data or a specific format, please contact fish biologist Jonathan Speegle at jonathan_speegle@fws.gov. Custom data requests will be handled as soon as possible; however, response times may be delayed under certain circumstances. We encourage users to contact the data managers to discuss which dataset is best suited to your needs. Complete data files that have undergone final quality checks are available on the Environmental Data Initiative Data Portal. Type DJFMP or EDSM into the search bar to access the data sets and accompanying program metadata. These files are updated periodically as final quality-assurance and quality-control measures are completed.
Chinook Salmon (Oncorhynchus tshawytscha) populations in California are in decline due to the combined effects of habitat degradation, water diversions, and shifting climate regimes. This project uses archival tissues (otoliths, vertebrae) from modern and ancient spring-run Chinook Salmon to understand how shifts in migration timing and habitat use allowed salmon to cope with highly variable environmental conditions. We will learn how salmon responded to the recent drought and flood periods (2012-2020 CE), the California Gold Rush Period (~1835-1870 CE), the Little Ice Age (~1560-1780 CE), and the Megadrought Period (~1200-1410 CE). This effort will provide the insights needed for developing climate-adapted conservation actions to support salmon into the future.
