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 Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>