Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny fish can yield big clues to Delaware River health

15.11.2007
Where have all the bridle shiner gone? That’s the mystery The Academy of Natural Sciences’ fish scientists are trying to answer, and the outcome will shed light on the environmental health of the Upper Delaware River.

The bridle shiner, a key indicator of the health of the Delaware River, is identified primarily by a distinctive black band that runs from the end of its nose to the base of its tail, and by its straw-colored body.

Bridle shiner—not easy to spot at less than two inches long—once were abundant in the mid-Atlantic region, including small streams in Southeastern Pennsylvania. Their steady decline has prompted Pennsylvania to classify the fish as endangered. Now, the Academy is swimming the tide to lay the groundwork for an environmental management plan for the species and its habitat.

The Academy’s Patrick Center for Environmental Research, in partnership with the Upper Delaware Scenic and Recreational River and the Delaware Water Gap National Recreation Area, is in the midst of a two-year project to discover and describe the status of the little minnow in the Upper Delaware River basin.

Academy fisheries scientists David Keller and Shane Moser, under the direction of Dr. Richard Horwitz, have cast their seine nets and gone snorkeling many times at various locations over the last year with varying results. Their findings will shed light on the health of the Upper Delaware River and will factor into decisions made about the flow of the river.

“The presence and absence of fish helps us define preferred habitat for the fish, which helps us locate potential sites for sampling,” explained Horwitz. “We've located several sites with populations of the species, and in other places we've found a few fish on one visit, but not on subsequent visits. These sites may lead us to sites with large populations.”

Academy studies reveal possible causes of the species’ decline may include changes in water quality due to siltation, nutrient enrichment and changes in flow patterns, and the introduction of predators, such as largemouth bass, as well as competitors for food. Interestingly, a decline in the beaver population also may factor into the decline.

“We’ve found bridle shiner in ponds formed by beaver activity,” said Horwitz. “Beaver were once extirpated or nearly extirpated in the region. Beaver have become re-established and numbers have been increasing, which may provide new habitats for the bridle shiner.”

The results of the Academy’s studies, which will continue into 2008, will factor into the Delaware River Basin Commission’s flow management plans for the river. Bridle shiner prefer slow-moving, shallow waters that flow over beds of aquatic plants. The Upper Delaware River region provides drinking water, supports a number of native fish species, and is popular for sport fishing and other recreational activities. Flow management can affect all these resources; in addition, flooding is a concern in some riverside communities.

“Our goal is to develop management plans to protect the fish and its habitat,” said Horwitz. “Water flow and temperature in the Upper Delaware River’s backwater habitats are key to doing this.”

The historical status of bridle shiner in Pennsylvania is known mostly from early 20thcentury collections held at the Academy. The species was originally described by naturalist Edward Drinker Cope, who discovered the fish in a tributary of the Schuylkill River in Conshohocken, Pa., where it no longer occurs. Cope’s personal collection of fishes, reptiles and amphibians was bequeathed to the Academy in 1898.

The research, supported by a Pennsylvania Department of Conservation and Natural Resources grant, will continue at least until June 2008.

The Academy is located at 1900 Benjamin Franklin Parkway and is open Monday through Friday from 10 a.m. to 4:30 p.m. and weekends until 5 p.m. Admission is $10 for adults, $8 for children ages 3-12, seniors, students with college I.D. and military personnel, and free for children under 3. There is a $2 fee for “Butterflies!”

The Academy of Natural Sciences, the oldest natural science research museum in the Americas, is a world leader in biodiversity and environmental research. The mission of the Academy is the encouragement and cultivation of the sciences.

Carolyn Belardo | EurekAlert!
Further information:
http://www.ansp.org

More articles from Ecology, The Environment and Conservation:

nachricht Five-point plan to integrate recreational fishers into fisheries and nature conservation policy
20.03.2019 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht Rain is important for how carbon dioxide affects grasslands
06.03.2019 | University of Gothenburg

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Molecular motors run in unison in a metal-organic framework

20.03.2019 | Life Sciences

Active substance from plant slows down aggressive eye cancer

20.03.2019 | Life Sciences

Novel sensor system improves reliability of high-temperature humidity measurements

20.03.2019 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>