Posts Tagged: ecosystem
Working with campus experts (such as faculty and staff in the Department of Wildlife, Fish and Conservation Biology) and local environmental and conservation organizations, the volunteer students are improving the habitats for local wildlife and engaging the public in hands-on activities.
This is an extraordinary program that gives the students real-world environmental management skills, along with leadership opportunities and communications experience. Professor John Eadie, Department of Wildlife, Fish and Conservation Biology at UC Davis, said of the Wild Campus program, “Hands-on activity is a huge part of the educational experience.”
A past project — Build a Wild Home Day — involved working with the UC Davis Arboretum on a successful public outreach program to build bird and bat boxes for installation on campus. (Great photos of this program are on the group’s Facebook page.)
The Wild Campus organization has a large cadre of eager and dedicated students who are improvising and making the most of limited resources. However, they are in need of donated field equipment (used equipment is fine) and financial contributions.
Visit the Wild Campus website and Facebook page for a feel-good look at what these ambitious students are doing to improve the environment, along with ways you can help them succeed.
At least 13 of the 102 aquarium species that are imported into California have been introduced into California marine waters, according to a recent report by Susan Williams, professor in the Department of Evolution and Ecology at UC Davis and a marine ecologist the Bodega Marine Laboratory. These introduced species have a high success rate (69 percent) in establishing themselves.
Two very invasive species — the predatory lionfish and Caulerpa seaweed (aka “killer algae”) — have reportedly come from the aquarium trade. The lionfish, which has established itself along the East Coast where it eats smaller fish and threatens reef ecological systems, has not yet reached California waters, but the Caulerpa seaweed cost California more than $6 million to eradicate from two Southern California lagoons a decade ago.
At least 34 aquarium species were found to be potential invaders in California marine waters.
“Globally, the aquarium trade has contributed a third of the world’s worst aquatic and invasive species,” Williams said. "Lionfish are voracious predators in their native habitats, and in their invaded habitat any predator is a potential threat to the native ecosystem."
Williams’ advice: "To avoid releasing aquarium species into natural water, don’t dump your aquarium where they can become an expensive and harmful pests.”
She said that people should contact the vendor where the fish was purchased or the California Department of Fish and Wildlife to learn how to dispose of aquarium species responsibly.
- Complete UC Davis news release, by Kat Kerlin
- Our AmazingPlanet report
- Environmental News Network report
- Science on NBC News report
The San Joaquin/Sacramento Delta and Suisun Marsh were once part of a continuous, enormously productive aquatic ecosystem that supported dense populations of fish from Sacramento perch to salmon, huge flocks of wintering waterfowl, and concentrations of mammals from beaver to tule elk. This amazing ecosystem is gone and cannot be brought back.
The once vast marshes have been turned into farmland and cities, protected by a complex system of levees. The patchy remnants of the original ecosystem are disappearing fast, as more and more native plants and animals become extinct or endangered. In their place, hundreds of alien species thrive in the altered conditions—crabs, clams, worms and fish from all over the world.
- We have a choice. We can let the ecosystem continue to slide towards being a mess of alien species that live in unsavory water flowing through unnatural pathways, or we can take charge and create a new ecosystem that contains the elements we want. Those elements include native species and clean water that flows in more natural patterns, creating a better environment for fish and people.
The State Water Resources Control Board recently supported this concept by recommending that much more fresh water flow through the estuary to the ocean to create a sustainable estuarine ecosystem. More water is only part of the recovery picture, however, because the flows must be managed in new ways and flow through restored habitats. The historical ecosystem can be used only as a model for the new system, mainly to identify conditions that favor remnant native species and have other desirable features. But the new ecosystem will be quite different in its locations, its biota, and how it works.
High variability in environmental conditions in both space and time once made the upper San Francisco Estuary highly productive for native biota, so variability is clearly a key concept for our new ecosystem (Moyle, et al. 2010). Achieving a variable, more complex estuary requires policies that create the following conditions:
- Internal Delta flows that create a tidally-mixed, upstream-downstream gradient in water quality, with minimal cross-Delta flows. At times much of the water in the present Delta flows towards the big export pumps in the South Delta. Fish trying to migrate upstream or downstream find this very confusing, often lethally so.
- Slough networks with more natural channel geometry and less diked, rip-rapped channel habitat.
- More tidal marsh habitat, including shallow (1-2 m) sub-tidal areas, in both fresh and brackish zones of the estuary.
- Large expanses of low salinity (1-4 ppt) open water habitat in the Delta.
- A hydrodynamic regime where salinities in the upper estuary range from near-fresh to 8-10 ppt periodically to discourage alien species and favor desirable species.
- Species-specific actions that reduce abundance of non-native species and increase abundance of desirable species, such as active removal of undesirable clams and vegetation.
- Abundant annual floodplain habitat, with additional large areas that flood in less frequent wet years.
- Treating the estuary as one inter-connected ecosystem, recognizing that changes in one part of the system will likely effect the other parts.
These habitat actions collectively provide a realistic, if experimental, approach to improving the ability of the estuary to benefit desirable species. Some of these goals are likely to be achieved without deliberate action as the result of sea level rise, climate change, and failure of unsustainable levees in some parts of the Delta. But in the near term, habitat, flow restoration and export reduction projects can allow creation of a more variable and more productive ecosystem than now exists, while accommodating irreversible changes to the system.
(This post first appeared on the CaliforniaWaterBlog.)
Update: The National Research Council has taken an interest in plans to conserve habitat for endangered and threatened species in the Sacramento-San Joaquin Delta while continuing to divert water for agricultural and urban use in Southern California. On May 5, the council declared the draft Bay Delta Conservation Plan incomplete, difficult to understand and still needing much work.
Moyle, P.B., J.R. Lund, W. Bennett and W. Fleenor (2010), Habitat Variability and Complexity in the Upper San Francisco Estuary, San Francisco Estuary and Watershed Science 8(3).
Cunningham, L. (2010), A State of Change: Forgotten Landscapes of California, Heyday Books, Berkeley.