Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Invasive species threaten critical habitats, oyster among victims

21.07.2009
A study of oyster reefs in a once-pristine California coastal estuary found them devastated by invasive Atlantic Coast crabs and snails, providing new evidence of the consequences when human activities move species beyond their natural borders.
Led by marine biologist David L. Kimbro, now of The Florida State University Coastal and Marine Laboratory , the study shows that in Tomales Bay , half the population of California's native Olympia oyster has perished because its habitat has fallen victim to the dysfunctional relationship between native species and non-native ones accidentally introduced.

The work of Kimbro, a postdoctoral associate at the FSU lab, and colleagues from the University of California-Davis and its Bodega Marine Laboratory has magnified concerns that predator-prey mismatches between native and exotic species may lead to further losses of critical habitats that support marine biodiversity and ecosystems.

"What David Kimbro's research reveals about California's Olympia oyster raises a specter for Florida as well," said Felicia Coleman, director of the FSU Coastal and Marine Laboratory.

"First, our state has a remarkably productive native oyster population at risk in the Apalachicola Bay ," she said. "These oysters are sustainably harvested and provide critically important settlement habitat for an amazing array of species, so its loss would be devastating. Second, we know that in Florida's benign climate, exotic species are pretty easily established. One need only follow the trajectories of lionfish, Australian pine, Brazilian pepper and Burmese python for a grim view through the looking glass."

Kimbro and colleagues describe their findings in a paper ("Invasive species cause large-scale loss of native California oyster habitat by disrupting trophic cascades") that was recently published in the online and print editions of the peer-reviewed journal Oecologia .

Their study is expected to help guide habitat management and conservation efforts, including plans now being drawn up along the West Coast to restore native oysters.

"We've identified what my California colleagues call 'an important restoration bottleneck,' the attack on oysters by invasive species, which must be dealt with prior to undertaking oyster population enhancement and the rebuilding of remnant reefs," Kimbro said.

In California, said Kimbro, the artificial predator-prey mismatch has allowed high numbers of invasive snails to destroy the biological diversity of Tomales Bay, a coastal estuary about 40 miles northwest of San Francisco, by consuming and eliminating oyster habitat.

As an example, he points to the invasive European green crab from the Atlantic Coast (inadvertently introduced from Europe, so an exotic species even there). Smaller than California's native crab, it is less effective at controlling the snail population because it uses only brute force to kill its prey -- unlike its native counterpart, which is capable both of crushing the snails and using its claws like a can opener to peel open hard-to-crush larger shells.

Ecological consequences are profound when the species most affected by a predator-prey mismatch is a "foundation species" that supports biodiversity by creating extensive habitat, such as California's native Olympia oyster (Ostreola conchaphila), which provides critical nursery habitat for a suite of species including crabs, anemones and fishes.

Although Olympia oyster reefs are normally preyed upon by native predatory snails, said Kimbro, they are somewhat protected by the presence of native rock crabs that both consume native snails and force all others to spend more time hiding from crabs -- rather than eating the oysters.

But when Atlantic snails and crabs invade, the whole dynamic changes.

"You'd think similar-looking invasive and native species could be swapped in a system without adverse effects," he said. "But we have shown that, functionally, this is not the case."

In Tomales Bay, the exotic species occupy its inner reaches, where saline levels are lower. However, native predators cannot tolerate the inner bay's lower salinity, so they can't help to check the invasive snail population proliferating there. The invasive crabs are stuck in the inner bay because the natives hold the middle, with its higher salinity. Once upon a time, native oysters enjoyed a release from predation in the inner bay -- that is, until the invasive species moved in.

"While native predator-prey interactions that benefit oyster reefs are intricate and took a long time to develop, the invasive crab and snail don't have the historical exposure necessary to recreate these important interactions," Kimbro said. "A fellow researcher likened the native crabs and snails to a long-married couple who have learned to coexist, leaving oyster populations intact. But the lack of experience the invasive crabs and snails have with each other has led to the destruction of parts of the oyster population, much as an incompatible couple might destroy an entire family."

In addition to principal investigator David L. Kimbro of The Florida State University Coastal and Marine Laboratory, co-authors of the paper in Oecologia are Edwin Grosholz, Adam Baukus, Sarikka Attoe, and Caitlin Coleman-Hulbert (University of California-Davis), and Nicholas Nesbitt and Nicole Travis (Bodega Marine Laboratory, Sonoma County, Calif.).

David Kimbro | EurekAlert!
Further information:
http://www.fsu.edu

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>