Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Underwater Elephants

30.07.2014

In the high-tech world of science, researchers sometimes need to get back to basics. UC Santa Barbara’s Douglas McCauley did just that to study the impacts of the bumphead parrotfish (Bolbometopon muricatum) on coral reef ecosystems at two remote locations in the central Pacific Ocean.

Using direct observation, animal tracking and computer simulation, McCauley, an assistant professor in the Department of Ecology, Evolution and Marine Biology, and his colleagues sought to understand whether the world’s largest parrotfish is necessary for positively shaping the structure and functioning of ecosystems. 

The answer, published in a recent issue of the journal Conservation Biology, is yes and no.“We actually swam alongside bumphead parrotfish for close to six hours at a time, taking detailed data on what they ate and where they went,” McCauley explained.“It was one of the more exhausting but wonderful experiences I’ve had as a field scientist.”Often more than 4 feet long and weighing in at more than 100 pounds, bumpheads are major coral predators; one fish can consume just over 2 tons of living coral in a year. 

They are also a threatened species in serious decline across the Pacific. Hunted throughout the region — often at night in sea caves where they sleep — they have cultural significance (i.e., they’re coveted for feasting ceremonies) among many Pacific islanders.“These large parrotfish crunch off entire pieces of reef and audibly grind them up into sand in their pharyngeal mill — specialized teeth in the back of their throat,” McCauley explained. 

“You know bumpheads are near when you begin noticing branches lopped off stony corals and golflike divot scars marking the reef.”McCauley’s research demonstrates that bumpheads exert a complex mix of positive and negative effects on reefs. On the plus side, bumpheads reduce the abundance of fast-growing algae that compete with corals for light and space. Their feeding helps corals reproduce by opening up space on reefs. 

In addition, when feeding, they can disperse small coral fragments around reefs that can later grow into adult coral colonies, just as birds disperse plant seeds.Conversely, bumpheads eat coral and this predation reduces its abundance and diversity. “They can completely consume small coral colonies, and the feeding scars they leave on large corals can be a source of physiological stress,” McCauley said. 

“The coral skeleton that they grind up and excrete falls also back atop corals as biosediment and this can amount to 50 tons of sediment a year from a school of bumpheads. Sedimentation in other contexts is known to contribute to the smothering of corals.”The team’s results highlight the diverse effects that species can have on ecosystems, adding a deeper perspective on understanding the ecological role of endangered species. McCauley noted that conservation often tacitly advances the expectation that endangered species must be good for the environment.“This viewpoint is ecologically misleading,” he added. 

“Most species do things to ecosystems that we would construe as both positive and negative. Endangered species are no different from their more abundant counterparts.” McCauley is quick to add that these findings by no means suggest that declining species like bumphead parrotfish are undeserving of protection.“We can, in fact, strengthen the integrity of the field of conservation biology by being rigidly objective about the observations we make in nature — even if this means reporting occasionally that rare species can damage ecosystems,” he added. 

“If anything, better understanding the full complement of ways that at-risk species use and affect their environment empowers us to more effectively protect them.“The case of the bumphead parrotfish is analogous in interesting ways to the African elephant,” McCauley continued. 

“African elephants are a vulnerable and imperiled species that can be agents of deforestation and reduce regional biodiversity.These effects are particularly strong in areas where elephants have been artificially confined in high-density aggregations. Science that describes how elephants reshape ecosystems can help managers more effectively approach the complicated task of reversing severe global elephant declines while protecting local ecosystems. Bumphead parrotfish are to coral reefs what elephants are to African savannas.” 
Contact Info: 

Julie Cohen
julie.cohen@ucsb.edu
(805) 893-7220

Julie Cohen | Eurek Alert!
Further information:
http://www.news.ucsb.edu/2014/014341/underwater-elephants

Further reports about: Biology Pacific colonies coral fragments corals ecosystems elephants parrotfish species

More articles from Life Sciences:

nachricht New Model of T Cell Activation
27.05.2016 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Fungi – a promising source of chemical diversity
27.05.2016 | Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie - Hans-Knöll-Institut (HKI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Worldwide Success of Tyrolean Wastewater Treatment Technology

A biological and energy-efficient process, developed and patented by the University of Innsbruck, converts nitrogen compounds in wastewater treatment facilities into harmless atmospheric nitrogen gas. This innovative technology is now being refined and marketed jointly with the United States’ DC Water and Sewer Authority (DC Water). The largest DEMON®-system in a wastewater treatment plant is currently being built in Washington, DC.

The DEMON®-system was developed and patented by the University of Innsbruck 11 years ago. Today this successful technology has been implemented in about 70...

Im Focus: Computational high-throughput screening finds hard magnets containing less rare earth elements

Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.

The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...

Im Focus: Atomic precision: technologies for the next-but-one generation of microchips

In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.

In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...

Im Focus: Researchers demonstrate size quantization of Dirac fermions in graphene

Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices

Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.

Im Focus: Graphene: A quantum of current

When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene

In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking 4.0: International Laser Technology Congress AKL’16 Shows New Ways of Cooperations

24.05.2016 | Event News

Challenges of rural labor markets

20.05.2016 | Event News

International expert meeting “Health Business Connect” in France

19.05.2016 | Event News

 
Latest News

3-D model reveals how invisible waves move materials within aquatic ecosystems

30.05.2016 | Materials Sciences

Spin glass physics with trapped ions

30.05.2016 | Materials Sciences

Optatec 2016: Robust glass optical elements for LED lighting

30.05.2016 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>