(Press-News.org) "Ocean predator" conjures up images of sharks and barracudas, but the voracious red lionfish is out-eating them all in the Caribbean – and Mother Nature appears unable to control its impact on local reef fish. That leaves human intervention as the most promising solution to the problem of this highly invasive species, said researchers at the University of North Carolina at Chapel Hill.
"Lionfish are here to stay, and it appears that the only way to control them is by fishing them," said John Bruno, professor of biology in UNC's College of Arts and Sciences and lead investigator of the study. The research has important implications not just for Caribbean reefs, but for the North Carolina coast, where growing numbers of lionfish now threaten local fish populations.
"Native predators do not influence invasion success of Pacific lionfish on Caribbean reefs" was published July 11 by the journal PLOS ONE.
Lionfish, native to the Indo-Pacific region, have long been popular aquarium occupants, with their striking stripes and soft, waving fins. They also have venomous spines, making them unpleasant fare for predators, including humans—though once the spines are carefully removed, lionfish are generally considered safe to eat, Bruno said.
They have become big marine news as the latest invasive species to threaten existing wildlife populations. Bruno likened their extraordinary success to that of ball pythons, now eating their way through Florida Everglades fauna, with few predators other than alligators and humans.
"When I began diving 10 years ago, lionfish were a rare and mysterious species seen deep within coral crevices in the Pacific Ocean," said Serena Hackerott, lead author and master's student in marine sciences, also in UNC's College of Arts and Sciences. "They can now been seen across the Caribbean, hovering above the reefs throughout the day and gathering in groups of up to ten or more on a single coral head."
The international research team looked at whether native reef predators such as sharks and groupers could help control the population growth of red lionfish in the Caribbean, either by eating them or out-competing them for prey. They also wanted to evaluate scientifically whether, as some speculate, that overfishing of reef predators had allowed the lionfish population to grow unchecked.
The team surveyed 71 reefs, in three different regions of the Caribbean, over three years. Their results indicate there is no relationship between the density of lionfish and that of native predators, suggesting that, "interactions with native predators do not influence" the number of lionfish in those areas, the study said.
The researchers did find that lionfish populations were lower in protected reefs, attributing that to targeted removal by reef managers, rather than consumption by large fishes in the protected areas. Hackerott noted that during 2013 reef surveys, there appeared to be fewer lionfish on popular dive sites in Belize, where divers and reef managers remove lionfish daily.
The researchers support restoration of large-reef predators as a way to achieve better balance and biodiversity, but they are not optimistic that this would affect the burgeoning lionfish population.
"Active and direct management, perhaps in the form of sustained culling, appears to be essential to curbing local lionfish abundance and efforts to promote such activities should be encouraged," the study concluded.
INFORMATION:
Bruno acknowledged the key contributions of Hackerott, who performed the work in his lab as part of her UNC undergraduate honors thesis. Click here for Hackerott's blog about her senior-year research experiences.
Other study participants were researchers from Simon Fraser University, British Columbia; Reef Environmental Education Foundation; Florida International University; National Oceanic and Atmospheric Administration—Florida Keys National Marine Sanctuary; and Dial Cordy & Associates, Miami.
Link to PLOS ONE publication: http://dx.plos.org/10.1371/journal.pone.0068259
Note: Professor Bruno may be reached by email, jbruno@unc.edu, or Twitter: @johnfbruno
Images: High-resolution images may be found here:
Lead author and UNC student Serena Hackerott and her study organism; photo credit: Katie DuBois http://goo.gl/dt8G2
Lionfish close up 1; photo credit: Abel Valdivia http://goo.gl/84c8K;
Lionfish close up 2; photo credit: Walter Hackerott http://goo.gl/Lbfkx
Video of the team's work may be found at http://vimeo.com/34401430: Sharks, grouper and lionfish coexisting in peace and harmony at Gardens of the Queen reef, Cuba. Shot by John Bruno, May 2011.
UNC News Services contact: Kathy Neal, interim health and science editor, kcneal@unc.edu or (919) 740-5673 (cell).
END
This week a European Earth-observing satellite confirmed that a large iceberg broke off of Pine Island Glacier, one of Antarctica's largest and fastest moving ice streams. The rift that led to the new iceberg was discovered in October 2011 during NASA's Operation IceBridge flights over the continent. The rift soon became the focus of international scientific attention. Seeing the rift grow and eventually form a 280-square-mile ice island gave researchers an opportunity to gather data that promises to improve our understanding of how glaciers calve.
"Calving is a hot topic ...
VIDEO:
The TRMM satellite flew over Soulik on July 10 at 14:06 UTC and saw a well-defined eye and multiple intense (red) and moderate and weak (green, blue).
Click here for more information.
When a hurricane or typhoon's eye becomes filled with clouds, it can be a sign the storm is weakening, or that high clouds have moved over it, or its eyewall is being replaced. When NASA's Aqua satellite passed over Typhoon Soulik on July 11 an instrument aboard noticed clouds filled ...
Tropical Storm Chantal moved over Hispaniola on July 10 when NASA's Terra satellite passed overhead from space, and less than twenty-four hours later the storm weakened to a remnant low pressure area.
The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite captured a visible image of Chantal when it was a tropical storm over Hispaniola on July 10 at 15:20 UTC (11:20 a.m. EDT). At that time, Chantal's northern quadrant covered the Dominican Republic and eastern Haiti while the center of the storm remained south of ...
Drug use is common among street children, posing serious threats to both their health and their chances for reintegration into society. It's difficult to reduce drug use among street children without a good understanding of the problem, and up to now the research has been confined mainly to local studies with inconsistent results. Today, Addiction has published a systematic review of 50 studies of drug use among street children in 22 countries, shedding new light on the magnitude of the problem, the causes and health consequences of drug use among street children, and ...
STANFORD, Calif. — A new, noninvasive technique for tracking stem cells after transplantation — developed by a cross-disciplinary team of radiologists, chemists, statisticians and materials scientists at the Stanford University School of Medicine — could help surgeons determine whether a procedure to repair injured or worn-out knees is successful.
The technique, described in a study to be published online July 12 in Radiology, relies on an imaging agent already approved by the U.S. Food and Drug Administration for an entirely different purpose: anemia treatment. Although ...
Young men who are gang members suffer unprecedented levels of psychiatric illness, placing a heavy burden on mental health services, according to new research led by Queen Mary, University of London.
The National Institute for Health Research (NIHR) and Maurice & Jacqueline Bennett Charitable Trust funded study surveyed 4,664 men aged 18 to 34 in Britain. The survey covered measures of psychiatric illness, violence and gang membership. It is the first time research has looked into whether gang violence is associated with psychiatric illness, other than substance misuse.
The ...
Spanish researchers at the Centro Nacional de Investigaciones Cardiovasculares (CNIC) have found that during the early stages of mammalian development, embryonic cells embark on a battle for survival. Through this battle, the less active of these cells are eliminated by their stronger sisters. The work is published today in the prestigious journal Nature.
This phenomenon, termed cell competition, occurs in a defined time window, between days 3 and 7 of mouse development. During this period all embryonic cells compete with each other, as explained by Dr. Cristina Claveria, ...
Human migrations – from the prehistoric epoch to the present day – have extended cultures across the globe. With these travelers have come unwanted stowaways: mosquito-borne parasites belonging to the Plasmodium species – a group responsible for malaria, worldwide.
As part of a team of collaborators from 10 countries, Ananias Escalante, a researcher at Arizona State University's Biodesign Institute, has been tracking the tenacious global spread of one of these malarial parasite species: Plasmodium vivax, the most prevalent cause of malaria in many countries outside ...
LOS ANGELES (July 11, 2013) – Deep brain stimulation therapy blocks or modulates electrical signals in the brain to improve symptoms in patients suffering from movement disorders such as Parkinson's disease, essential tremor and dystonia, but a new study suggests that several factors may cause electrical current to vary over time.
Led by Michele Tagliati, MD, director of Cedars-Sinai Medical Center's Movement Disorders Program, the study identified variables that affect impedance – resistance in circuits that affect intensity and wavelength of electrical current. Doctors ...
Medical diagnostic and security scanners with higher sensitivity could result from University of Adelaide research into detecting T-rays (terahertz waves).
Published in the journal Advanced Optical Materials, the researchers describe a novel structure which traps terahertz waves in tiny (micro-scale) holes to produce much higher contrast imaging than currently possible.
Terahertz waves, which are electromagnetic waves with frequencies between those used for mobile phone communications and for optical fibre communications, are used for some airport body scanners and ...
