Virus' extensive geographic range and number of species infected might make it largest known marine wildlife disease to date
Museum biological collections are the records of life on Earth and as such, they are frequently used to investigate serious environmental issues. When public health officials were concerned about the levels of mercury in fish and birds, for example, scientists studied museum specimens to assess historical changes in mercury contamination.
Eggs in museum collections were analyzed to establish the connection between DDT, thinning eggshells, and the decline in bird populations. And now, specimens from the Natural History Museum of Los Angeles County (NHM) have helped explain the mysteriously sudden appearance of a disease that has decimated sea stars on the North American Pacific Coast.
In a paper published Monday, November 17, 2014 in the journal Proceedings of the National Academy of Sciences, Cornell University microbiologist Ian Hewson and colleagues identify the Sea Star Associated Densovirus (SSaDV) virus as the microbe responsible for Sea Star Wasting Disease (SSWD). NHM Curator of Echinoderms Gordon Hendler and Collections Manager Cathy Groves, along with scientists from universities and aquariums along the coast (including NHM neighbor, the California Science Center), collaborated in the study.
Since June 2013, the largest die-off of sea stars ever recorded has swept the Pacific Coast. At least 20 different species of sea stars have been affected -- including iconic species like the "ochre star" and the multi-armed "sunflower star" -- and many populations of sea stars from Southern Alaska to Baja California have already disappeared.
Their large-scale disappearance is anticipated to have a serious and long-lasting ecological impact on coastal habitats, because sea stars are voracious predators, with a key role in regulating the ecology of the ocean floor.
Museum samples prove that the virus has existed at a low level for at least the past 72 years -- it was detected in preserved sea stars collected in 1942, 1980, 1987, and 1991. The study suggests the disease may have recently risen to epidemic levels because of sea star overpopulation, environmental changes, or mutation of the virus.
The study detected the virus on particles suspended in seawater, as well as in sediment, and showed that it is harbored in animals related to sea stars, such as sea urchins and brittle stars. Likely it can be transported by ocean currents, accounting for its rapid, widespread dispersal in the wild. Since the die-off began, the disease has caused a mass mortality of captive sea stars in aquariums on the Pacific Coast, although it did not spread in aquariums that sterilize inflowing seawater with UV light.
"There are 10 million viruses in a drop of seawater, so discovering the virus associated with a marine disease can be like looking for a needle in a haystack," Hewson said. In fact, the densovirus is the first and only virus identified in sea stars. However, its discovery will enable scientists to study how the virus infects sea stars and trace it in the ocean. Further research could reveal how the virus invades its host, why kills some sea stars, and why other species are unaffected.
Research might also identify factors that triggered the ongoing plague and help to predict or forestall similar events in the future.
"A recent publication highlighted examples of innovative studies for which museum time-series were integral in identifying responses to environmental change and bemoaned general decline in the growth of museum collections," said NHM's Hendler. "Fortunately, we bucked the trend and intentionally collected common, local species of sea stars, which made it possible to detect SSaDV in specimens from NHM!"
About the Natural History Museum:
The Natural History Museum of Los Angeles County is a national leader in research, exhibitions and education. The Museum was the first dedicated museum building in Los Angeles, opening its doors in 1913. It has amassed one of the world's most extensive and valuable collections of natural and cultural history -- with more than 35 million objects, some as old as 4.5 billion years. For more information, visit the Museum's website at http://www.nhm.org or call (213) 763-DINO.
Kristin Friedrich | EurekAlert!
Value from wastewater
16.08.2017 | Hochschule Landshut
Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).
The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
16.08.2017 | Physics and Astronomy
16.08.2017 | Materials Sciences
16.08.2017 | Interdisciplinary Research