About the Delta Interagency Invasive
Species Coordination (DIISC) Team


The DIISC Team (web link) was formed in 2013 to foster communication and collaboration among California state agencies that detect, prevent, and manage invasive species and restore invaded habitats in the Sacramento-San Joaquin Delta.  The DIISC Team includes state agency program managers and scientists, and benefits from participation by research and conservation groups and other stakeholders. The DIISC Team also has involvement from key federal agencies.

As outlined in the Invasive Species Coordination Framework, the goals of the DIISC Team are to establish a framework for:

  • Strategic planning
  • Coordinated implementation
  • Education and outreach
  • Data management
  • Research needs
  • Funding
The figure is a flow chart that begins with Invasive Species Coordination with arrows that point forward to Agencies and Organizations Working in the Delta as well as back to Invasive Species Coordination. From Invasive Species Coordination, there are also arrows that point down to 5 different categories: Exchange Information, Implementation, Education and Outreach, Funding, and Research and Monitoring. Here these 5 categories and the specific tasks under each of the categories are described as a list. Category 1: Exchange Information. Tasks: exchange information to improve efficiencies and support strategic planning and implementation, and climate change. Category 2: Implementation. Task: detection and control. Category 3: Education and Outreach. Tasks: develop and coordinate effective education and outreach, and outreach to legislation. Category 4: Funding. Task: identify funding needs and potential funding sources for research, strategic implementation, and education and outreach. Category 5: Research and Monitoring. Tasks: leverage and share current scientific developments, prioritize the research, and climate change.


Invasive species are non-native species whose introduction causes or is likely to cause harm to economies, environment or human health.  The Delta is among the world’s estuaries most-invaded by non-native species.  At least 185 non-native species are currently present and new species will likely arrive.

The many historical changes to the Delta have made the area more hospitable to certain non-native species. These factors include changes in the timing and volume of flows, salinity levels and other water quality indicators, and reduction and shifting of habitat. Climate change is also expected to favor non-native species over natives.

Although many non-native species will likely remain in the Delta, harmful ecological, economic, and human health impacts from invasive species can be minimized by preventing new introductions and controlling existing ones. Since there is no singular lead entity for managing invasive species in the Delta, the DIISC Team provides a needed forum for the agency collaboration and communication that is essential to preventing and controlling the negative impacts of invasive species.


The DIISC Team meets quarterly. Contact Thomas Jabusch at thomas.jabusch@deltaconservancy.ca.gov (email link) for information on upcoming meetings. 

Invasive Animal Species in the Delta

A brown-colored Chinese mitten crab (Eriocheir sinensi). Photo by CDFW.
Chinese mitten crab – Eriocheir sinensi
(Photo by CDFW)
Many tan-colored New Zealand mudsnails (Potamopyrgus antipodarum) shown with a dime for size reference. Photo by U.S. Geological Survey.
New Zealand mudsnails – Potamopyrgus antipodarum
(Photo by U.S. Geological Survey)
A northern watersnake (Nerodia sipedon) with brown and tan stripes in the grass next to a rock. Photo by Patrick Coin.
Northern watersnake – Nerodia sipedon
(Photo by Patrick Coin)
A nutria (Myocastor coypus) animal with brown fur, white whiskers and orange teeth. Photo by CDFW.
Nutria – Myocastor coypus
(Photo by CDFW)
Five dark brown/tan-striped and five light brown/tan-striped Quagga Mussels (Dreissena rostriformis bugensis) shown next to a dime in a person's hand for size reference. Photo by CDFW.
Quagga Mussels – Dreissena rostriformis bugensis
(Photo by CDFW)
A southern watersnake (Nerodia fasciata) with tan, brown, and red-striped skin in the grass. Photo by CDFW.
Southern watersnake – Nerodia fasciata
(Photo by CDFW)
Three Zebra mussels (Dreissena polymorpha) with brown and tan-color stripes.
Zebra mussels – Dreissena polymorpha

Invasive Plant Species in the Delta

The white flower and green leaves of an alligatorweed (Alternathera philoxeroides) plant. Photo by National Plant Data Center, Baton Rouge, LA.
Alligatorweed – Alternathera philoxeroides
(Photo by National Plant Data Center, Baton Rouge, LA)
A section of the Brazilian egeria (Egeria densa) plant. Photo by Lara Gudmundsdottir.
Brazilian egeria – Egeria densa
(Photo by Lara Gudmundsdottir)
Brown, fluffy seedheads and green leaves of the nonnative common reed (Phragmites australis subsp. australis) plant. Photo by Erlend Bjortvedt.
Common reed – Phragmites australis subsp. australis
(Photo by Erlend Bjortvedt)
Curlyleaf pondweed (Potamogeton crispis) plants in the water. Photo by Christian Fischer.
Curlyleaf pondweed – Potamogeton crispis
(Photo by Christian Fischer)
Eurasian watermilfoil (Myriophyllum spicatum) in the water. Photo by Fungus Guy.
Eurasian watermilfoil – Myriophyllum spicatum
(Photo by Fungus Guy)
Giant reed (Arundo donax) plants growing in the Sacramento-San Joaquin Delta.
Giant reed – Arundo donax
White flowers and green leaves of the perennial pepperweed (Lepidium latifolium) plant. Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org.
Perennial pepperweed – Lepidium latifolium
(Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org)
Purple loosestrife (Lythrum salicaria) plants with purple flowers and green leaves. Photo by Liz West.
Purple loosestrife – Lythrum salicaria
(Photo by Liz West)
South American spongeplant (Limnobium laevigatum) in the water. Photo by Cardex.
South American spongeplant – Limnobium laevigatum
(Photo by Cardex)
Purple water hyacinth (Eichhornia crassipes) flowers with yellow and blue markings and green leaves growing in the water. Photo by Wouter Hagens.
Water hyacinth – Eichhornia crassipes
(Photo by Wouter Hagens)
The flower and leaves of a water primrose plant (Ludwigia spp.). Photo by Bouba.
Water primrose – Ludwigia spp.
(Photo by Bouba)