Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Bird Vomit, Feathers Serve as Environmental Indicators

When Charles Clarkson finishes a day's work in the field, he commonly is covered with vomit. In fact, he collects it. "Regurgitates," he politely calls his rather extensive collection of bird upchuck.

Clarkson is a University of Virginia Ph.D. candidate in environmental sciences who is conducting a comparative study of bird populations on Virginia's Eastern Shore and in New York Harbor.

He collects vomit and bird feathers from nestlings as a way to compare the diets of birds from each location and to see how the local environments affect nutritional intake, and ultimately, the overall health of bird populations. The samples also serve as a means for assessing the quality of the environments in which the birds live.

Clarkson chose the two study sites because they represent extreme opposites in environmental quality. The Eastern Shore site is in a nearly pristine area that has been protected by the Nature Conservancy for 40 years. The New York Harbor site, by contrast, is heavily polluted and adjacent to the activities of an enormous human population.

"There's heavy boat traffic at the mouth of the Hudson River, which is notorious for high-level contaminates, such as mercury," Clarkson said. "This allows a good comparative study between two vastly different locations that support the same species of birds."

Clarkson is focusing on two bird species, the glossy ibis and the double-crested cormorant. These birds represent both ends of the feeding spectrum of a range of shorebird species.

"The glossy ibis is a habitat-use specialist that probes for food in the mud, while the double-crested cormorant is a habitat-use generalist, a species that can be found in fresh, brackish or salt water and consumes a wide variety of fish species," Clarkson said.

When he enters a nesting site, the nestlings vomit as a defense mechanism.

"It makes my job easy because I can go into a colony, pick up the nestlings and they will regurgitate into a bag for me," he said.

He also collects a feather from each bird, and then takes the samples back to a lab for analysis. From the stomach content, he can determine which species of fish were consumed and the diversity and apparent abundance of those species, and he can assess the mercury levels in those foods and, therefore, the birds' diets.

"I can tell a lot about the environments in which they live and, likewise, the overall health of the overall environments in which we all live," he said. "I also can analyze feathers and determine if these feathers are growing normally or at a slower rate and if they're denuded. I can correlate that with the diet the bird is getting, and the contaminate load that the bird is getting as well.

"Initial indications seem to be that the feather growth bars are wider in Virginia birds than New York birds, which likely means better nutritional conditions on the Eastern Shore, whether from dietary abundance or quality," Clarkson said.

"The New York birds have narrower growth bars, likely as a result of some deficiency in diet." A growth bar is a part of the feather that develops within a 24-hour period and is a good indicator of nutritional intake during that time period.

Likewise, New York birds are developing more "fault bars" – thin patches in their feathers that indicate a variety of stresses, such as predation or disturbances from human activity.

"Fault bars mean that nestlings are devoting more of their energy resources to immuno-suppression than to feather growth," Clarkson said. "So the feather has less actual substance to it."

This means the birds must use more energy and effort to fly and maintain warmth, making them susceptible to diseases and predators.

"The overall implications of the research are that we can start to answer questions about local habitat health by a simple measure of how a feather is developing as related to diet, rather than just the traditional method of population surveys," Clarkson said. "This allows us to isolate the sources of insult that bird species are facing. I'm hoping the study will broaden our horizons in terms of the tools that are at our disposal for conservation and assessing overall environmental health."

Fariss Samarrai | Newswise Science News
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>