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Captive Delta Smelt
The two latest editions of the IEP Newsletter - Volume 40, Issue 1 (Supplemental) and Volume 40, Issue 2 - are now available! Visit our
page for more information. Don't forget to suscribe to our Newsletter list so you can receive the next edition in your mailbox. If you want to receive updates on other IEP products, visit our
page to sign up for all of them at one time. The next issue of the newsletter will be edited by the USFWS and submissions are due by October 15, 2021. Contact Geoff Steinhart (
) for questions on submitting an article.
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.
The Culture and Supplementation of Smelt (CASS) Steering Committee has released its
solicitation proposal for the cultured Delta Smelt 2022 brood year-class (PDF)
. The solicitation includes information on the criteria that will be used to evaluate each proposal received. This solicitation will represent the
opportunity to request cultured Delta Smelt for 2022. All proposal requests must be submitted to the director of the FCCL, Dr. Tien-Chieh Hung at
on or before September 30, 2021
A remote informational meeting to answer questions on the solicitation proposal and discuss research priorities will be held on
July 30, 2021 at 12:00 p.m
. Meeting details and phone number can be found in the
solicitation proposal (PDF)
By the summer, many Bay-Delta fish have spawned and are beginning to recruit to juvenile and adult life stages within the standing stock or population. One of the tools IEP agency scientists use to track these recruiting fish is the
Summer Townet Survey
. Check out how we catch, count, and index fish encountered in the warmer summer waters of our Estuary!
Local authors featured in Special Issue
– The September 2021 volume of
Estuaries and Coasts
, the journal of the Coastal and Estuarine Research Federation, focusing on “Concepts and Controversies in Tidal Marsh Ecology Revisited,” is now available. Editors and authors in this volume will be familiar to Bay-Delta scientists and stakeholders. This featured volume includes several Open Access articles including Dr. Colombano and colleagues’ “
Climate Change Implications for Tidal Marshes and Food Web Linkages to Estuarine and Coastal Nekton.
New Sampling Platform Described
– To help address uneven successes in sampling across different habitats within the Estuary, Merz et al. describe a sampling platform desgin ( a fancy pontoon boat) that can add efficiency to our littoral sampling collections, among others. Their article from
Frontiers in Environmental Science
is available online now.
Delta Smelt Life History Model application
– Using a "state-space" population modeling approach, Smith and colleagues examine details from Delta Smelt life history and discuss causes of mortality using data from 1995-2015. Find their most interesting article in the
Canadian Journal of Fisheries and Aquatic Sciences
IEP Technical Reports Available
The latest IEP Technical Report titled “
Interagency Ecological Program Long-term Monitoring Element Review: Pilot approach and methods development (2020)
,” is now available. This report describes results and recommendations from the year-long review of several long-term surveys as a pilot effort leading to a review of all IEP Long-term monitoring surveys as part of the IEP Annual Work Plan. Further information can be obtained by contacting lead authors Jereme Gaeta (
) or Steven Culberson (
). Please visit our IEP Web site for more information about our
and additional program information.
The IEP Technical Report "
Synthesis of data and studies relating to Delta Smelt biology in the San Francisco Estuary, emphasizing water year 2017
(FLOAT-MAST IEP Technical Report 95)" and its
is now available. A two-page summary document accompanies the report and serves as a quick overview of findings. The two-page summary is available on the
IEP Technical Publications
web page. One bottom line from the report summary:
High fall outflow may be important, but outlfow alone is not sufficient to provide favorable conditions for Delta Smelt.
High flows in 2017 resulted in many good habitat characteristics for Delta Smelt but smelt did not have the expected high survival or abundance.
High temperatures in 2017 may have stopped Delta Smelt from thriving.
Using DNA to Identify Prey Items
Delta Science Program
Scientist Dr. Brandl and colleagues published a paper investigating predation on species of concern in the San Francisco Estuary. Entitled “Enumerating Predation on Chinook Salmon, Delta Smelt, and Other San Francisco Estuary Fishes Using Genetics,” The manuscript “investigated (1) patterns of piscivore catch and prey detection across the northern Delta, (2) spatial and temporal patterns in Striped Bass prey composition, and (3) habitat attributes associated with Striped Bass consumption of two key native ﬁshes of concern (Chinook Salmon and Delta Smelt). The article is available at the
North American Journal of Fisheries Management
Report Available on Delta Primary Productivity
– A fact sheet-like report entitled “Delta Landscapes Primary Production: Past, Present, Future” is available from the
San Francisco Estuary Institute
. This report places into important context opportunities and limitations for restoring food web productivity in the Sacramento-San Joaquin Delta and broader San Francisco Estuary.
Featured Dataset Publication on EDI
Hartman, R.K., N. Rasmussen, E. Wells, A.J. Stewart, C.E. Burdi, and T. Sommer. 2021. Interagency Ecological Program: Water quality, fish, phytoplankton, clams and zooplankton monitoring to support the Summer-Fall Suisun Marsh Salinity Control Gates Action 2018-2020 ver 1. Environmental Data Initiative.
The Suisun Marsh Salinity Control Gates (SMSCG) have the potential to increase low-salinity-zone habitat for endangered Delta Smelt (
, California Endangered Species Act listed as Endangered, Federal Endangered Species Act listed as Threatened), and to allow them to more frequently occupy Suisun Marsh, especially Montezuma Slough, one of their most important rearing habitats. Operation of the SMSCG in summer and fall to improve Delta Smelt habitat are called for in the Biological Opinion and Incidental Take permit for the Central Valley Project and State Water Project. To support the adaptive management of the action, the California Department of Water Resources monitored the change in water quality, phytoplankton, zooplankton, fishes, and clams resulting from the action in 2018. This data package includes data collected by the Interagency Ecological Program’s (IEP) long-term monitoring programs supplemented with targeted sample collection where existing surveys lack spatial or temporal coverage. This package also includes modeling the change in Delta Smelt habitat based on area of open water with appropriate temperature, salinity, and turbidity. Monitoring during no-action years (2019 and 2020) will be used as a baseline for comparison during action years. This data package will be updated annually during both action years and non-action years.
Check out the
for upcoming Project Work Team, Stakeholder Group meetings and other IEP related events!
October 6 Biotelemtry Project Work Team meeting 9:00 a.m. - 12:00 p.m.
October 7 Coordinators Meeting (internal event) 9:00 a.m. - 12:00 p.m.
October 7 Winter-Run Chinook Salmon Project Work Team meeting 1:00 p.m. - 3:00 p.m.
October 13 Aquatic Vegetation Project Work Team meeting 1:00 p.m. - 4:00 p.m.
October 20 Science Management Team meeting (internal event) 1:00 p.m. - 4:30 p.m.
October 21 Estuarine Ecology Team Project Work Team meeting 9:00 a.m. - 12:00 p.m.
Other Events or News
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.
Dr. Larry Brown, research biologist with the U.S. Geological Survey and recognized expert of California fishes was unanimously chosen as the recipient of the
2021 Brown-Nichols Science Award
IEP Lead Scientist, Steve Culberson, discusses what it will take to understand the complex San Francisco Estuary ecosystem and continue to shift ecosystem management from the simple to the complex. Check out his post
Complexities: Thinking about the San Francisco Estuary during the 2021 Bay-Delta Science Conference
on his Delta Stewardship Council page.
Until further notice IEP meetings/gatherings are being held remotely/virtually.
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