The study says 60 out of 68 U.S. species, or 88 percent of fish species found exclusively in large-river ecosystems like the Mississippi, Missouri and Ohio rivers, are of state, federal or international conservation concern. The report is in the April issue of the journal Frontiers in Ecology and the Environment.
On the other hand, says lead author Brenda Pracheil, a postdoctoral researcher in the UW’s Center for Limnology, the study offers some good news, too.
Traditionally, the conservation emphasis has been on restoring original habitat. This task proves impossible for ecosystems like the main trunk of the Mississippi River — the nation’s shipping, power production, and flood control backbone. While the locks, dams and levees that make the Mississippi a mighty economic force have destroyed fish habitat by blocking off migration pathways and changing annual flood cycles species need to spawn, removing them is not a realistic conservation option.
But, says Pracheil, we’re underestimating the importance of tributaries. Her study found that, for large-river specialist fish, it’s not all or nothing. Some rivers are just big enough to be a haven.
For any river in the Mississippi Basin with a flow rate of less than 166 cubic meters of water per second, virtually no large-river specialist fishes are present. But in any river that even slightly exceeds that rate, 80 percent or more of the large-river species call it home.
That means Mississippi tributaries about the size of the Wisconsin River and larger are providing crucial habitat for large-river fishes. When coupled with current efforts in the large rivers themselves, these rivers may present important opportunities for saving species.
“Talk to any large-river fish biologist, and they will tell you how important tributaries are to big river fish," says Pracheil. "But, until now, we’ve not really understood which rivers are most important. Our study tackles that and shows which tributaries in the Mississippi River Basin show the most promise for conservation of large-river fishes.”
Current policies governing large river restoration projects are funded largely through the U.S. Army Corps of Engineers, which requires that funds be spent on mainstems — or the big rivers themselves. Pracheil's study suggests spending some of that money on tributary restoration projects might do more conservation good for fish, while also letting agencies get more bang for their habitat restoration buck.
“Tributaries may be one of our last chances to preserve large-river fish habitat,” Pracheil says. “Even though the dam building era is all but over in this country, it’s just starting on rivers like the Mekong and Amazon — places that are hotspots for freshwater fish diversity. While tributaries cannot offer a one-to-one replacement of main river habitats, our work suggests that [they] provide important refuges for large-river fishes and that both main rivers and their tributaries should be considered in conservation plans.”
Brenda Pracheil, 402-613-0315, firstname.lastname@example.org
Brenda Pracheil | Newswise
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