PRESS-NEWS.org - Press Release Distribution
FREE PRESS RELEASES DISTRIBUTION

Crunching on coral

Research finds that coral predators exert a much larger influence on young coral than expected

Crunching on coral
2021-04-07
(Press-News.org) You might not think an animal made out of stone would have much to worry about in the way of predators, and that's largely what scientists had thought about coral. Although corallivores like parrotfish and pufferfish are well known to biologists, their impact on coral growth and survival was believed to be small compared to factors like heatwaves, ocean acidification and competition from algae.

But researchers at UC Santa Barbara have found that young corals are quite vulnerable to these predators, regardless of whether a colony finds itself alone on the reef or surrounded by others of its kind. The research, led by doctoral student Kai Kopecky, appears in the journal Coral Reefs.

Kopecky and his co-authors were curious how corals can reemerge following large disturbances like cyclones and marine heatwaves, which periodically devastate the reefs of Mo'orea, French Polynesia, where the research was conducted.

"Mo'orea is prone to big heat shocks, storm waves, cyclones and predatory sea star outbreaks," said co-author Adrian Stier, an associate professor in the Department of Ecology Evolution & Marine Biology and one of Kopecky's advisors. "It just wipes the slate clean in terms of coral death. And sometimes, just a few years later, you can swim around and see thriving life. We're still really curious about what allows these ecosystems to bounce back."

Scientists had implicated predators in shaping coral population dynamics, but there hadn't really been many direct studies. "People who study coral reefs have thought a lot about the supply of new babies coming from elsewhere, or limitation by the amount of nutrients, or competition with algae as important drivers of coral recovery," Stier continued. "But there hasn't been as much done on the importance of predators as a limiting factor."

After reviewing the literature on coral growth, mortality and predation, Kopecky decided to focus on the effects predation and density had on young coral colonies.

He planted small nubbins of Pacific staghorn coral at various locations on the reef either alone, in a group of four, or in a group of eight. Some of these groups were protected by metal cages, while others were left exposed. For the unprotected coral, Kopecky sought to determine whether high density increased or decreased predation on the staghorn. For the protected groups, he was curious how density influenced coral growth.

The researchers found that protection was key to these small corals' futures. After 30 days out on the reef, nearly all of the unprotected nubbins had been completely consumed. In fact, density had virtually no effect on this outcome.

The researchers let the experiment run for an entire year. When they returned, virtually none of the unprotected specimens remained. On the other hand, the caged corals had outgrown their accommodations by year's end.

"The corals that were protected grew all the way into the upper corners of the cages and were poking little branches out," Kopecky recalled. "They formed a cube of coral inside the cages, whereas the ones that were exposed to predators were just barely hanging on."

Coral are not typically fast-growing organisms, but staghorn coral grows quickly, giving it a competitive edge following disturbances that remove large amounts of coral. But according to Kai, staghorn coral are like the popcorn chicken of the reef: irresistible to a hungry corallivore.

The protected corals grew so quickly that Kai had to adopt a different way to measure them, because at a certain point the nubbins fused, and he could no longer unscrew their base plates to measure them in the lab.

So, if there's no protection in numbers for these tasty staghorns, how do they ever survive their infancy?

The corals benefit from the protection of fish like the Dusky farmerfish, which farms algae on the reef. These farmer fish doggedly defend their territories, offering protection to any small coral that happens to settle in their range, Kopecky explained. And while algae and coral are often considered archenemies -- with the former able to outcompete the later -- by munching on their crops, the farmer fish keep the algae in check. This enables the coral to get through the stage where they're vulnerable to predation.

In fact, researchers rarely see staghorn corals in large colonies absent the protection of these fishy farmers, Kopecky added.

The authors thought density would have some effect on predation. "I think it just turns out that this coral is so tasty that predators simply mowed everything down," Stier remarked.

The team is considering running a similar experiment with cauliflower coral, which is more robust and slower-growing than the staghorn. Hopefully it's also slightly less scrumptious, as well.

"When these pufferfish eat enough, you can see their bellies weighted down by the coral rocks that are in their stomachs," Stier said. "I mean, they're oddly shaped fish to begin with; they're already having a hard time swimming without that ballast, but this makes it extra tricky."

"It really is a cartoonish dynamic," Kopecky added.

Staghorn coral is widely used in reef restoration efforts, especially in the Caribbean where this and a related species (elkhorn coral) are endangered. In fact, before joining UC Santa Barbara, Kopecky spent several months working as a coral restoration technician on the U.S. Virgin Islands.

"I had an opportunity to see coral restoration in action, but also see some of the limitations associated with it," Kopecky said. "And then I was able to go and conduct research, like this experiment, that can feed back into and inform how restoration might be improved."

Getting out-planted coral nubbins through this vulnerable life stage presents a major bottleneck to restoration efforts, Kopecky explained. He has already received feedback on the study from people engaged in coral reef restoration expressing how relevant his findings are to their work.

"When you protect these young, vulnerable corals from predators, the amount of growth is substantially higher than when they're not protected," Kopecky said. "It's clear that coral predators can really shape whether young corals actually reach the size where they're no longer vulnerable to predation."

INFORMATION:


[Attachments] See images for this press release:
Crunching on coral

ELSE PRESS RELEASES FROM THIS DATE:

Unraveling the mysteries of sleep disorders in multiple system atrophy

Unraveling the mysteries of sleep disorders in multiple system atrophy
2021-04-07
Unusual diseases are medical mysteries that fascinate us, and one such disease is multiple system atrophy, or MSA. This rare neurological disorder causes failures in the proper functioning of the body's autonomic system (processes that are not under our conscious control, such as blood pressure, breathing, and involuntary movement). The resulting symptoms can look like two other types of neurodegenerative disease: Parkinson's disease and cerebellar ataxia. In fact, MSA can be separated into a parkinsonism subtype or a cerebellar subtype based on whether the resultant movement-related ...

Junctions between three cells serve as gateways for the transport of substances

Junctions between three cells serve as gateways for the transport of substances
2021-04-07
Within multicellular organisms, cells build connections with each other forming cell layers that cover the surfaces of tissues and organs and separate structures in the body. For example, the skin forms a mantle around the entire organism, and the layer of cells lining the blood vessels creates a boundary between the bloodstream and tissues. Special connections between neighbouring cells ensure that these cellular barriers are, on the one hand, stable and tight - thus protecting the body and organs against pathogens - while, on the other hand, they remain permeable to specific substances or migrating cells. This is how the cells allow dissolved ...

Framework could support more reliable electric power distribution systems

2021-04-07
Imagine the process of distributing electricity to homes from the power grid is like travelers boarding a train. There are multiple steps to take before they can reach their final destination. First, they have to buy a ticket at the ticketing booth - this is where the power is generated. Then, they board a train that departs from the station - the power is transmitted over distances using transmission lines. Finally, the train takes the travelers (electricity) to their final destination. This final step of sending power to homes and businesses is called the distribution system - and it is critical that ...

Mounting hope for new physics

2021-04-07
Today, the Muon g-2 Collaboration finally published the highly anticipated first result from its measurement of the anomalous magnetic moment of the muon, a precision quantity that offers physicists one of the most promising means to test predictions of the actual Standard Model of particle physics. The measured value, which is more precise than all values before, strengthens evidence for the emergence of new physics beyond the Standard Model, and thus for the existence of previously unknown particles or forces. The result was presented at an online ...

For girls, learning science outside linked to better grades, knowledge

2021-04-07
In a new study, North Carolina State University researchers found that an outdoor science program was linked to higher average science grades and an increase in a measure of science knowledge for a group of fifth grade girls in North Carolina. The findings, published in the International Journal of Science Education, indicates outdoor education could be a promising tool to help close gender gaps in science. "The outdoors is a space where teachers can find tangible ways to make science come alive," said the study's lead author Kathryn Stevenson, assistant professor of parks, recreation and tourism management at NC State. "The natural environment is also a place that everybody has in common. In a way, it's also a great context for employing reform-based teaching practices ...

Conspiracy theories and cognitive biases in the COVID-19 pandemic

2021-04-07
Conspiracy theories appear to be increasing in popularity as the Covid-19 pandemic continues. But to what extent do people really agree with them, and what is the association with cognitive biases? A research team from the University of Basel studied these questions in German-speaking Switzerland and Germany. Periods of crisis are often conducive to the emergence and spread of conspiracy theories, and the Covid-19 pandemic is a case in point. A research team led by Sarah Kuhn and Dr. Thea Zander-Schellenberg of the University of Basel has investigated the endorsement rates of coronavirus-related conspiracy theories in German-speaking Switzerland and Germany, ...

Particle physics: Will muons lead us towards a new physics?

2021-04-07
Muons, particles akin to electrons, have kepts physicists' heads spinning for more than a decade, because an experimental measurement of their magnetic properties (1) disagrees with theory. Could this be caused by unknown particles or forces? A new theoretical calculation of this parameter, involving CNRS physicists and published in the journal Nature, has reduced the discrepancy with the experimental measurement. The debate nevertheless continues. -- For over 10 years, measurement of the magnetic properties of the muon (an ephemeral cousin of the electron) has exhibited disagreement with theoretical predictions. This ...

800-year-old medieval pottery fragments reveal Jewish dietary practices

800-year-old medieval pottery fragments reveal Jewish dietary practices
2021-04-07
A team of scientists, led by the University of Bristol, with archaeologists from Oxford Archaeology, have found the first evidence of a religious diet locked inside pottery fragments excavated from the early medieval Jewish community of Oxford. Keeping kosher is one of the oldest known diets across the world and, for an observant Jew, maintaining these dietary laws (known as Kashruth) is a fundamental part of everyday life. It is a key part of what identifies them as Jews, both amongst their own communities and to the outside world. Oxford's Jewish quarter was established around St. Aldates in the twelfth and thirteenth centuries, following William the Conqueror's invitation ...

Gender inequality study shows women under-represented on marketing academic journal boards

2021-04-07
Women are significantly underrepresented in the editorial boards of marketing academic journals, and awards and recognition favour men, new research from the University of Bath School of Management has found. In their study 'It's hard to be what you can't see - gender representation in marketing's academic journals', Professor Andrea Prothero of Business and Society at University College Dublin and co-researcher Professor Pierre McDonagh examined gender representation in 20 marketing academic journals through three areas - the gender composition of editorial boards, special issue celebrations ...

Losing weight through exercise

Losing weight through exercise
2021-04-07
Worldwide 39 percent of the adults were overweight in 2016, according to statistics of the World Health Organization. In the US the prevalence of obesity was 42.4 percent in 2017/2018, according to a survey of the National Center for Health Statistics (NCHS). Concurrently millions of people want to lose weight. Physical exercise is an important option to achieve this. After all, more calories are consumed through sport than when sitting, standing or lying down. But what influence does sport have on (direct) eating habits? Scientists at the Technical University of Munich (TUM) and the University of Nebraska (USA) have now investigated this ...

LAST 30 PRESS RELEASES:

E-cigarettes with a cigarette-like level of nicotine are effective in reducing smoking

Deep Learning model developed at UHN to maximize lifespan after liver transplant 

Convenience over reputation: Study looks at how older adults pick a doctor

Ocean bacteria release carbon into the atmosphere

Spotting cows from space

Scientists watch 2D puddles of electrons emerge in a 3D superconducting material

Research suggests SEC's increasing focus on terrorism may limit financial oversight

Plastic planet: Tracking pervasive microplastics across the globe

Gut epithelium muscles up against infection

Scientists discover three liquid phases in aerosol particles

New mechanism identified behind blindness in older adults

Common approach to diversity in higher education reflects preferences of white Americans

Study reveals cancer immunotherapy patients at most risk of life-threatening side effects

Study reveals crucial details on skin-related side effects of cancer immune therapies

Researchers identify surface protein as a new osteosarcoma therapeutic target for antibody-drug conjugates

Differences in B cell responses to coronaviruses and other pathogens in children and adults

Bottom-up is the way forward for nitrogen reduction at institutions

Road salts and other human sources are threatening world's freshwater supplies

Researchers engineer probiotic yeast to produce beta-carotene

Spanking may affect the brain development of a child

UConn researchers find bubbles speed up energy transfer

Antidepressant use in pregnancy tied to affective disorders in offspring; no causal link

Binge-eating is not caused by stress-induced impulsivity

Stress does not lead to loss of self-control in eating disorders

USC Stem Cell study reveals neural stem cells age rapidly

Following atoms in real time could lead to better materials design

People want to improve mental health by exercising, but stress and anxiety get in the way

More than the sum of mutations

Living foams

Research brief: How pharmacists contribute meaningfully in primary health care

[Press-News.org] Crunching on coral
Research finds that coral predators exert a much larger influence on young coral than expected