Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

"Snowbirds" versus real birds

15.12.2003


Southern vacation resorts encroaching on key winter habitats crucial to success of migratory birds: Queen’s researchers



(Kingston, ON) – The destruction of tropical forests to create vacation resorts for human “snowbirds” who fly south from Canada and the northern U.S. every winter is creating serious breeding problems for real migratory birds, say Queen’s University biologists.

A new study, headed by Ph.D. student Ryan Norris and his advisor, Professor Laurene Ratcliffe, shows for the first time that declining winter habitats of migratory songbirds significantly affect their ability to reproduce when they return north in the spring – and the evidence is found in tiny drops of their blood.


The study, highlighted recently in the journal Science, and co-authored by Dr. Peter Marra of the Smithsonian Institute, appears on-line in the current Proceedings of the Royal Society: Biological Sciences, and will be published in an upcoming print edition of Proceedings.

“Our findings help explain why many species of long-distance migratory songbirds have declined over the last few decades,” says Mr. Norris, noting that a relatively small geographic band – across the Caribbean, Greater Antilles, and central America – is the annual destination of an estimated five billion migratory birds flying south each year from Canada. The species in this study is a small, migratory warbler called the American redstart.

Until now, understanding how and why these migratory populations are declining has been a problem, since it is difficult to track individuals throughout their yearly travels. A new technique for detecting “biological signatures” provides the solution.

Using equipment and expertise of the Queen’s Facility for Isotope Research (QFIR) headed by geology professor Kurt Kyser, the team measures stable carbon isotopes found in the warblers’ blood. These samples are taken immediately after the birds arrive at the university’s biological field station north of Kingston, Ontario in the spring.

Since the turnover time of the blood cells is from six to eight weeks, they provide a good indicator of the quality of the birds’ previous habitat on the wintering ground. The carbon signature of each redstart has been deposited by insects the bird ate, and the insects in turn fed on vegetation growing in the winter habitat. “It’s basically a ‘food chain signature’,” says Mr. Norris.

The researchers first determined what were high and low quality habitats for redstarts, which winter in the Caribbean and central America, and breed in deciduous forest throughout Canada and the U.S. They found that what makes a better winter habitat is primarily the degree of wetness, particularly at the end of the season (late winter/early spring) when low quality habitats tend to dry out.

The second step was to develop isotope “markers” that identify the quality of each type of habitat. Next, blood samples were taken from warblers in their breeding grounds, and finally the birds’ reproductive success was measured by counting the number of “fledged” offspring to leave their nests.

The study, funded by the Natural Sciences and Engineering Research Council (NSERC), Canada Foundation for Innovation (CFI), and National Science Foundation (NSF), shows that redstarts wintering in high quality habitats, such as mangroves and lowland tropical forests, arrive earlier on the breeding grounds, nest earlier, and are more successful in producing young.

“Our work shows that destroying these high quality habitats has a disproportionate effect on the redstart populations: they lose the areas most capable of supporting them,” says Dr. Ratcliffe.

“As biologists, to see such a significant effect on the birds’ reproductive success is absolutely fascinating,” the biology professor continues. “Now we’ll need to go much deeper to discover all the complexities, and to determine if there are applications to other organisms as well.”

Nancy Dorrance | Queen´s University
Further information:
http://qnc.queensu.ca/story_loader.php?id=3fd87ff1b2480

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

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

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>