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Captive Delta Smelt
The Culture and Supplementation of Smelt Steering Committee has released the solicitation proposal for 2023 brood year fish. See the
(PDF) on the annual process to request cultured Delta Smelt from the University of California, Davis Fish Conservation & Culture Laboratory (FCCL) from the 2023 year-class. Requests must be submitted to the director of the FCCL, Dr. Tien-Chieh Hung at
on or before
September 30, 2022
The USGS California Water Science Center recently published their
California Waters Spring 2022 - Volume II - Issue II newsletter
. The purpose of the newsletter is to keep readers updated with current research projects, the latest publications, and other work the center is doing. Check out the article on identifying the source and taxa of cyanobacteria that are producing Microcystins, which are being detected in the San Francisco Bay.
Experimental Release of Delta smelt into the Wild for the First Time (PDF)
- During the week of December 17, 2021, the U.S. Fish and Wildlife Service, the California Department of FIsh and Wildlife, the California Department of Water Resources, the U.S. Bureau of Reclamation along with our partners at U.S. Geological Survey and UC Davis, experimentally released captively produced Delta smelt into the Sacramento-San Joaquin River Delta.
Photos and videos
from the release can be viewed and downloaded from the U.S. Fish and Wildlife Service's California-Great Basin Region
The 2021 summer/fall edition (Volume 40, Issue 3) of the IEP Newsletter is now available on our
page. No submissions were received for the 2022 winter edition, so no issue will be published. The call for articles for the 2022 spring edition of the newsletter was June 15. That edition should be coming out shortly! Have a question regarding the IEP Newsletter? Send it to
. Don't forget to
to our Newsletter list so you can receive the next edition in your mailbox.
Biologists from California State Parks, the Interagency Ecological Program, and other agencies have identified a new weed in the Delta. The species is Ribbon Weed (
Ribbon Weed Fact Sheet (PDF)
provides more information on how to recognize it and report it. So far, it has been documented at Rio Vista Delta Marina Yacht Harbor, Long Island, Hogback Island Boat Launch, Liberty Island, Mokelumne River near Lighthouse Marina, and Sherman Lake. Please report any sightings to Trish Gilbert (
) at the California Department of Parks and Recreation, Division of Boating and Waterways.
Smelt Larva Survey
– Many native fish use cooler temperatures in winter and early spring to time their spawning activities. Heat stress may be at a minimum this time of year, and seasonally higher stream flows can help disperse pelagic larvae. The
Smelt Larva Survey
, initiated in January 2009, provides near real-time distribution data for longfin smelt larvae in the Delta, Suisun Bay and Suisun Marsh. These data are used by agency managers to assess vulnerability of longfin smelt larvae to entrainment in south Delta export pumps.
How is the IEP Community thinking about climate change and understanding how to consider impacts to the Estuary now and into the future?
Find out by reading a review paper published in
San Francisco Estuary and Watershed Science
in the latest issue: Herbold, B.; Bush, E.; Castillo, G.; Colombano, D.; Hartman, R.; Lehman, P., et al. (2022). Climate Change Impacts on San Francisco Estuary Aquatic Ecosystems: A Review. San Francisco Estuary and Watershed Science, 20(2).
IEP authors add an article in Frontiers for Young Minds
This journal’s target audience is school aged children, and all the articles are reviewed by a school-aged reviewer. Pretty cool! The article adds to an impressive collection in
Frontiers for Young Minds
that describes how we monitor larval and juvenile fish:
A group of heavy-hitting IEP-affiliated research professionals have assembled what amounts to a primer for using eDNA as detection method in estuaries
The synopsis of a 2020 symposium at UC Davis can be found in
Estuaries and Coasts
. Here’s the citation: Nagarajan, R.P., Bedwell, M., Holmes, A.E. et al. Environmental DNA Methods for Ecological Monitoring and Biodiversity Assessment in Estuaries. Estuaries and Coasts (2022).
Remotely-sensed data and information products are increasingly being incorporated into analyses for understanding Estuary ecology
This innovative approach has recently been used to identify long-term declines in habitat conditions for the Delta Smelt over the period 1985-2019. Halverson and others recently published their manuscript in Environmental Science and Technology. Citation:
Decline in Thermal Habitat Conditions for the Endangered Delta Smelt as Seen from Landsat Satellites (1985–2019
). Gregory H. Halverson, Christine M. Lee, Erin L. Hestir, Glynn C. Hulley, Kerry Cawse-Nicholson, Simon J. Hook, Brian A. Bergamaschi, Shawn Acuña, Nicholas B. Tufillaro, Robert G. Radocinski, Gerardo Rivera, and Ted R. Sommer. Environmental Science & Technology 2022 56 (1), 185-193.
Pursuing improved management practices for Spring-Run Central Valley Chinook Salmon using regulations associated with State and Federal Incidental Take Permits has led to a publication outlining issues to be considered for that management
The latest issue of
San Francisco Estuary and Watershed Science
includes this article: Nelson, P. A; Baerwald, M.; Burgess, O. (; Bush, E.; Collins, A.; Cordoleani, F., et al. (2022). Considerations for the Development of a Juvenile Production Estimate for Central Valley Spring-Run Chinook Salmon. San Francisco Estuary and Watershed Science, 20(2).
Green sturgeon in the San Francisco Estuary show a variety of life history strategies based on acoustic telemetry data
Find out more in this article in
Environmental Biology of Fishes
: Thomas, M.J., Rypel, A.L., Singer, G.P. et al. Movement patterns of juvenile green sturgeon (Acipenser medirostris) in the San Francisco Bay Estuary. Environ Biol Fish (2022).
Featured Dataset Publication
he IEP Aquatic Vegetation Project Work Team (PWT) has published a new dataset and is linked on the
Environmental Data Initiative
data repository site.
See Khanna, S., S.L. Ustin, M.C. Lay, M. Andrew, M.J. Santos, E.L. Hestir, K.D. Shapiro, J. Bellvert, and J.A. Greenberg. 2022. Submersed Aquatic Vegetation community multi-year data from the Sacramento - San Joaquin Delta in California ver 1. Environmental Data Initiative.
Since 2007, field data have been collected in the Sacramento - San Joaquin Delta in northern California for the purpose of training and validating invasive species maps derived from remote sensing imagery over the Delta. The field crew collected submersed aquatic vegetation (SAV) species location data. For each point they noted attributes such as species name(s), location, cover estimates, and patch size. In addition, a thatching rake tethered to a rope was thrown off the side of the boat and pulled back out of the water; Secchi depth was measured using a Secchi disk and depth to the SAV mat was estimated by the field crew. Points were collected in patches larger than 9 square meters (3 m x 3 m). Point locations were measured using high precision (sub-meter accuracy) Trimble DGPS units (Trimble Navigation Limited, Sunnyvale, California) with Wide Area Augmentation System (WAAS) differential correction. All data points were exported as ArcGIS shapefiles and projected to UTM Zone 10N, Datum WGS-84 however this dataset includes the Latitude and Longitude of each point in decimal degrees. The spatial and attribute data quality was checked by examining photos of the data points and confirming the identity of the documented species.
USFWS researchers associated with sampling efforts at the Estuary’s Liberty Island have published a compiled dataset documenting biological collections since about 2002 on the EDI Repository.
See Gilbert, M.D., L. Smith, G. Steinhart, and IEP. 2021. Interagency Ecological Program and US Fish and Wildlife Service: Juvenile/Larval Fish and Zooplankton collections at Liberty Island, California 2002-2005 & 2013-2019 ver 1. Environmental Data Initiative.
The U.S. Fish and Wildlife Service (USFWS) Lodi Fish and Wildlife Office (LFWO) Delta Juvenile Fish Monitoring Program (DJFMP) has intermittently sampled Liberty Island with various equipment since 2002. Liberty Island was a reclaimed agricultural island until it flooded in 1997-1998 and we subsequently left to passively restore as a tidally influenced wetland. Larval trawls and beach were the only sampling methods used during both early (2002-2005) and late (2009-2019) sampling periods. The main purpose of the sampling was to gather information about fish presence and abundance in Liberty Island during the passive restoration, with an emphasis on reproductive and early life-stages of native species. Larval trawls, or tow nets, were used to catch larval fish in 2004-2005 and again from 2013-2019. Zooplankton nets were used 2013-2019. Water quality measurements were collected alongside each tow.
Check out the
for upcoming Project Work Team, Stakeholder Group meetings and other IEP related events!
August 15 Genetics PWT Meeting from 1:00 p.m. to 3:00 p.m.
August 24 Zooplankton PWT Meeting from 1:30 p.m. to 3:30 p.m.
Other Events or News
Delta Science Program - National Center for Ecological Analysis and Synthesis (DSP-NCEAS) 2021 Synthesis Working Group
This working group provides high-quality training in synthetic data science and statistical techniques and offers an opportunity for enhanced collaboration between agency and academic scientists. The group leverages training and a collaborative setting to analyze drivers of the Delta's estuarine food supply. Products from this working group will offer strong scientific support to inform decision-making for restoration, the protection of endangered species, and the management of flow actions. More information about the effort, including resources developed during the 2021 Synthesis Workshop can be found on the
Recording of the Delta Smelt Individual Based Model Workshop is now available. This is the first of two planned workshops on the updated Delta Smelt Individual Based Model (DSIBM) developed jointly by USFWS' San Francisco Bay Delta Fish and Wildlife Office, University of Maryland Center for Environmental Science (UMCES), and San Francisco State University Estuary & Ocean Science Center. The newly updated DSIBM expanded its capacity to evaluate effects of environmental variables, proposed long-term water operation plans (e.g., flow and entrainment), and other management actions (e.g., hatchery delta smelt supplementation, food enhancement, habitat restoration) on delta smelt population dynamics.
Until further notice IEP meetings/gatherings are being held remotely/virtually.
Frontiers for Young Minds
provides a collection of freely available scientific articles by distinguished scientists that are shaped for younger audiences by the input of their own peers.
Where the river meets the ocean - Stories from San Francisco Estuary
is a collection of stories from IEP scientists that tell; how people, plants, and animals use the San Francisco Estuary.
IEP Blogs -
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The View from Here
- A blog by the IEP Lead Scientist, Steve Culberson
Views from the Water
- A blog by our IEP survey field crew members
Science Stories: Adventures in Bay-Delta Data
- A blog by Rosemary Hartman (DWR), one of IEP's Synthesis Team members
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