Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Jellyfish Blooms Shunt Food Energy from Fish to Bacteria

08.06.2011
A new study by researchers at the Virginia Institute of Marine Science (VIMS) shows that jellyfish are more than just a nuisance to bathers and boaters, drastically altering marine food webs by shunting food energy from fish toward bacteria.

An apparent increase in the size and frequency of jellyfish blooms in coastal and estuarine waters around the world during the last few decades means that jellies’ impact on marine food webs is likely to increase into the future.

The results of the study, led by recent VIMS Ph.D. graduate Rob Condon—now a faculty member at the Dauphin Island Sea Lab (DISL) in Alabama—appear in the latest issue of the Proceedings of the National Academy of Sciences. His co-authors are VIMS professors Deborah Steinberg and Deborah Bronk, Paul del Giorgio of the Université du Québec à Montréal, Thierry Bouvier of Université Montpellier in France, Monty Graham of DISL, and Hugh Ducklow of the Marine Biological Laboratory in Woods Hole, Massachusetts.

Condon conducted his field studies by sampling jellyfish blooms in the York River, a tributary of lower Chesapeake Bay. The team’s experimental work took place in laboratories at VIMS, and in Canada and France. The researchers tracked the flow of food energy in the lab by measuring the amount of carbon taken up and released by jellyfish and bacteria within closed containers during “incubation” experiments of varying length. Carbon is the “currency” of energy exchange in living systems.

“Jellyfish are voracious predators,” says Condon. “They impact food webs by capturing plankton that would otherwise be eaten by fish and converting that food energy into gelatinous biomass. This restricts the transfer of energy up the food chain, because jellyfish are not readily consumed by other predators.”

Jellyfish and Marine Bacteria
Jellyfish also shunt food energy away from fish and shellfish that humans like to eat through their affects on the bacterial community. “Marine bacteria typically play a key role in recycling carbon, nitrogen, phosphorus, and other byproducts of organic decay back into the food web,” says Condon. “But in our study, we found that when bacteria consumed dissolved organic matter from jellyfish they shunted it toward respiration rather than growth.”

The upshot of this “jelly carbon shunt” is that bacteria in jelly-laden waters end up converting carbon back to carbon dioxide, rather than using it to grow larger or reproduce. This means the carbon is lost as a direct source of organic energy for transfer up the food web.

The researchers think the shift toward bacterial respiration happens because jellyfish produce organic matter that is extra rich in carbon. They do so through excretion and the sloughing of mucus. “The mucus is the slime you feel when you pick up a jelly,” says Steinberg.

The jellyfish in Condon’s experiments released large quantities of carbon-rich organic matter—with 25- to 30-times more carbon than nitrogen. That compares to a ratio of 6 parts carbon to 1 part nitrogen for the organic matter found dissolved in typical marine waters.

“The bacteria metabolized this carbon-rich material two to six times faster than they did with dissolved organic matter from water without jellyfish,” says Condon. “This rapid metabolism shunted carbon toward respiration rather than production, reducing their potential to assimilate this material by 10% to 15%.”

Steinberg says that bacterial metabolism of dissolved organic matter from jellyfish is like “drinking Gatorade” while metabolism of dissolved organic matter from phytoplankton and other sources is like “eating a hamburger.” “It just doesn’t provide an efficient food source for marine bacteria,” she says.

The Microbial Community
A final significant finding from the team’s research is that an influx of dissolved organic matter from jellyfish blooms changes the make-up of the local microbial community. “Dissolved organic matter from jellyfish favored the rapid growth and dominance of specific bacterial groups that were otherwise rare in the York River,” says Condon. “This implies that jelly-DOM was channeled through a small component of the local microbial assemblage and thus induced large changes in community composition.”

Overall, says Condon, the team’s findings “suggest major shifts in microbial structure and function associated with jellyfish blooms, and a large detour of energy toward bacteria and away from higher trophic levels.”

He adds that a host of factors, including climate change, over-harvesting of fish, fertilizer runoff, and habitat modifications could help to fuel jellyfish blooms into the future. “Indeed,” he says, “we’ve seen this already in Chesapeake Bay. If these swarms continue to emerge, we could see a substantial biogeochemical impact on our ecosystems.”

“Simply knowing how carbon is processed by phytoplankton, zooplankton, microbes or other trophic levels in space and time can lead to estimates of how much carbon energy is available for fish to consume,” he said. “The more we know, the better we can manage ecosystem resources.”

David Malmquist | Newswise Science News
Further information:
http://www.vims.edu

Further reports about: Chesapeake Bay Condon DISL Food Chain Plus Marine science VIMS bacteria blooms marine food web

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>