Whats seven feet long, 250 million years old, and currently lurking in the depths of Oregons Rogue River? Its the green sturgeon, the craggy, shark-like fish that has quietly eked out a living since the time of the dinosaurs. But according to a new study published by researchers from the Bronx-Zoo based Wildlife Conservation Society and other groups, this living fossil is extremely vulnerable to both overfishing and habitat alteration such as water diversion for irrigation and pollution. The study appears in the current issue of the Journal of Applied Ichthyology.
Using radio-tracking techniques, the authors of the study found that once green sturgeon enter freshwater rivers to spawn they spend long periods of time in extremely small home ranges -- sometimes just a 50-by-50 yard pool -- shared by numbers of individuals. This, coupled with the fact that the fish breeds in just three North American rivers, including the Rogue in Oregon, and the Klamath and Sacramento in California, makes it particularly sensitive to human impacts.
"This study shows that green sturgeon can easily become the victims of human exploitation and habitat loss," said Wildlife Conservation Society biologist Dan Erickson, the lead author of the study. "Precautionary management measures, such as the current sport-fishing regulations in the Rogue, may be justified to protect populations throughout its limited range."
Stephen Sautner | 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
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
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...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences